I've been an Automotive Tech from way back in the 1980's. I have a background as a Machinist and currently work as a Technician in a hi-tech manufacturing facility. Your presentation is one of the BEST I've seen regarding TTY fasteners, Torque Angle, etc. My family has owned at least 10 Subarus over the years an still owns 3 that are 10 years old or more. All running great. You've always been a Go-To source for all things Subaru. Great job and thank you!
It was concise, on point, especially how it relates to Scoobie Doo owners and all the myths that cause many to panic and wind up spending a lot of money that they otherwise would not need to. Keep up the good work!
Replaced head gaskets on 2001 fozzy 5 years ago. I didn't remove the engine from car , as there was enough room . I replaced head gaskets at 182,000 , now has almost 245,000
totally not scatterbrained, actually easy to follow and understand. my confidence level to approach this job is definitely higher after watching. i just need to find a good machine shop in my area to take the heads to
Very well explained. The use of mechanical fasteners is, in general, not well understood. I began to understand years ago when torquing the 3" diameter studs on a nuclear reactor cover plate using a heater in the hollow stud, a 50-ton bridge crane to stretch the stud while the nut was screwed down hand-tight. Crane tension released, nut/stud perfectly torqued to spec, no evil stuff able to leak out the seal.
I have been following you for a while now but.... I ALWAYS learn something new (or confirm what I believed.. a tech for 38 yrs. Love Subaru. Never worked at dealership. So learned on the fly So once again thank you for teaching us and confirming things I love the videos and it's so nice to prove to somebody else that the bolts are reusable lol So many parts first say no they're not reusable...You have to buy new ones.... 😂
@Mr. Subaru, This was exceptionally well explained! Great video and am looking forward to more! Especially if they can pertain to post 2008 Foresters in the future. Thanks again for all your work in sharing your knowledge! I actually like instructional videos where you do a detailed review of aspects of previous repairs. Just as a FYI of my view... I am not as interested in tool reviews from you, although they are excellent, because those are a dime a dozen on RUclips. I come to your channel for Subaru content and Subaru content only. MUCH APPRECIATED!
Very happy to know your opinion is something I can agree with. I have done a minimum of 50 Subaru head gasket or engine jobs in private shops and never once replaced head bolts. Never ever had a premature failure. 👍👍
The general rule is if it is a 'stretch bolt' aka TTY, to toss the fastener out. Its junk after it stretches. I run ARP'S on all my stuff so I reuse them all day. Good video, nice to see someone break down the B.S. better than I can lol
Too long, but subject was well-covered. Two things: To really know if the bolts might actually stretch to yield (stay elongated) you must measure the actual bolt before and after, much like you measure rod bolts when tightening. It might even be possible to strip out the threads before you get to yield, but I doubt it unless the case threads have see a lot of use or the bolt threads were bad and damaged the case threads. Secondly, I wish you had mentioned the use of assembly lube (like ARP sells) and whether that is allowable for lubrication versus motor oil. I would think it would actually be better and give more consistent torquing due to less friction than with plain oil. The final tightening by degrees is dependent on the last torquing being accurate, even though it is a moderately low number and not a lot of friction is involved. Thanks for making the video!
We don't replace them unless we have a creaking issue, and even then we just grab a HB out of the bin. wire wheel threads, oil threads, moly between the washers and your good.
Not only CAN you teach an old dog new tricks, an old dog can learn from a newer dog. The fact that this video set the record Straight regarding tty bolts is actually less significant for me. The greatest part, is that this gives me hope for the younger generations.
Absolutely a good idea as long as the cavity isn't overloaded with oil, coolant, etc. You can hydro lock the threads and actually crack the part your bolting it to. Excess fluid can also throw off the torque accuracy in some instances. A dab on the threads and under the washer is all you need. It's good practice to use a blowgun to blow out all the threads to make sure one hasn't filled up with crap before you bolt it down. You hit on everything that anyone who turns a wrench should know. I actually commented on this before I even watched a minute of the video so we think alike here. Definitely touched on all the points here. 👍👍
Hi When I put my machined heads on the new Subaru Short block on my 2008 Subaru Legacy GT Turbo - I was pretty nervous about this whole area and bought new head bolts. The dealership mechanic said re-use old ones. Machine shop who did the heads said I was nuts to do that - and get new ones (they won out in my mind - I got scared). Heck, I still have the old ones. This is most helpful to know I didnt need to do that. Thanks!
Michael Lusk Rule of thumb doesn’t always hurt to listen to a Subaru tech. They’ve got experience. However can’t say I blame you, there are hacks out there. Anyway hope your legacy gt is doing well. Love those cars
Mr Subaru...You are an excellent teacher and really good at explaining the details and also showing examples of doing it. I have never owned or worked on a Subaru but your mechanic methods could apply to many applications l'm sure. I'm hooked on watching your videos and enjoy reading the comments.
Eric O. at SMA is trying to sell a lift if you're interested. I just know you're back to the dirt and this might be an option for when you get a building sorted. Only a few states away!
When doing h/gaskets on my 98 WRX, I found using NEVER-SEEZ,pure nickel special, anti seize compound on h/bolts. Eliminates all grabbing and gives a beautiful smooth tightening transition. Been in engineering since 1970,and swear by this stuff. Cheers from Australia and my old REXY is still hammering!
Hello Mr Subaru, Great video, explaining key points on the tightening of the CH and very helpful when doing my Suby CH. The Tensile Stress-Strain presentation was very easy to follow and on point. Thank you for the video.
Used factory bolts are better than new aftermarket bolts. Aftermarket bolts always have dinged up threads and are never as straight as genuine bolts. If you are anal buy new bolts from the dealer, otherwise inspect your old bolts and reuse them. Subaru changed the torque sequence over and over throughout the ej engine era although they are all essentially the same. It's all bs, Subaru engineers purposely used inferior head gaskets on all of the N/A motors, knowing that they will fail at 100k. All of the turbo motors use mls gaskets that never fail because the engineers knew they wouldn't make it through the warranty period otherwise. The dohc turbo mls gaskets actually fit the sohc N/A motors, if you use these they will never leak again. Oil the bolts well, use turbo gaskets and torque bolts to 80 lb-ft and they will never leak again.
Awesome. Case closed! I spent hours researching this topic when replacing the head gaskets on my first engine. I finally settled on reusing the bolts but because of all the conflicting info I was still nervous about it. Now doing a second engine and because of this video I have 110% confidence that reusing them is fine. Thanks man! One thing that would be interesting to know is what exactly is the difference between the corner and center bolts? Different grade steel or something? Also, why are they different in the first place? Because they're getting torqued to slightly different specs the bolts have to be different? Just curious about that...
I know it's two year too late, but I have what I believe to be an answer for you... Imagine that we had 2 cylinders, but we keep the heads separate. You would expect 8 bolts total, since you need 4 each to hold down each head. Now imagine that we take those separate cylinders and merge them together side-by-side as close as we can. As you get them closer and closer, eventually the 4 inner most bolts would become superimposed on each other. Since objects can't occupy the same space at the same time, you would have to get rid of some bolts. Doing this you would arrive at a 6 bolt single head, as is what we see with our EJ's. What should be immediately obvious from this logic is that the 2 center bolts must necessarily be doing the work of 4 bolts if the system is to function the same as it had being separate cylinders. TL;DR, it's a "four bolt to a cylinder" design at it's core, just the two cylinders share the center bolts for space economy efficiency reasons. Hope that sorts things out for you, but especially anyone else reading this in the future.
Considering I found a broken factory torqued head bolt in lower cyl 4 position when I popped the heads off my ej205, I went ARP studs on the full rebuild
I think what you're trying to say is that torque is only a measurement of the rotational force exerted to tighten the bolt. That's not directly measuring the actual clamping force it's putting on the head/gasket/block interface. So, since you can't directly measure that force, you just have to base it on the torque of the bolt, hence the angle measurement.
In tool & die jargen, they look like Chicago screws made to get you more movement for inaccuracies of manufactured parts. It looks like we have a new use for them.
Is there a nice to see somebody on the internet that knows what he's talking about it puts a good joke in there and makes it so I can understand what I'm doing
I've reused my EZ30 NA head bolts with no issue. I cleaned and deoiling them. Then oiled the thread. Spun on the manual with all the moments and twists. The bolt did not produce any creaks. And I wasn't first who did that with my EZ30.
When i young I rebuilt a ej25. Did not know to oil threads for the head bolts. Freshly rebuilt block from machine shop. Hour later it went back. As I attempted to tighten the head bolts dry😞(SNAP!!!!) broken the bolt in two
My wife inherited a 2012 4cyl. Outback with 50K miles. I noticed on one of your videos that you said a 2012 headgasket will eventually fail...it is just a matter of time. With that in mind, I am contemplating having the timing belt changed this summer because I have the belief that timing belts should be changed either at 80K or 8 years old. I acquired this belief from personal experience. IUO, when I have the timing belt changed, should I have the head gaskets changed too? Time and convenience are very important to me, and the expense is a tertiary concern. I would like to have your opinion.
I suppose that the ARP stud kits cost a lot more than a new set of factory head bolts (are people in the field substituting cheap new Chinese head bolts for the Factory item or are there counterfeit head bolts floating around out there ?) I guess the ARP studs come with their proper washers and nuts?
Absolutely GREAT video!!! Answers many questions with great details and facts. Yet I have more questions. Does Subaru ever use Torque-To-Yield bolts? If my Subaru has standard head bolts, are Torque-To-Yield bolts NOT recommended? If one purchases new Torque-To-Yield bolts, would the torque sequence / process be different from the official Subaru process? If so, where may I find the proper torque sequence / process for the Torque-To-Yield bolts?
Great videos and very informative! I know you said we need to torque first to squish then back bolts before final torque, assuming you're using the oe single layer steel vs the Subaru uncoated MLS gasket for EJ253 SOHC NA. But is the squish step necessary for the MLS type gaskets? I've heard some subi techs skip squish step. My 02 Honda civic 1.7 SOHC NA has MLS and it didnt call for a squish and final torque step. Per your recommendation, im going to be using the mls on my subi, the design is the same as their oe single layer steel gasket. Thanks for all the help and great videos
I'm glad you asked that question. I was wondering the same thing. I've done about 4 HG jobs and i always re use my bolts and like you i don't do a squish of the HG before; i use PermaTorque MLS gaskets. In fact, i do my torque sequence a lil different. 11ft/l bs on all 6, then 25 ft/lbs on the two center bolts, then starting at the center i do 90 degree torque sequence twice. haven't had issues yet.
When I hear "stretch bolt", I just take it as gearhead slang for a "torque to yield " bolt, but it is a misnomer. Every tension type fastener you tighten from a tiny woodscrew to the head bolts on giant ship diesels stretches. Everything is a spring of sorts, every material has a spring rate. 10 ft lbs on a 2" diameter bolt just doesn't stretch it much. Most bolts are tightened only within their elastic range, traditionally, and reaching the yield strength means you've permanently deformed it, it's junk. Intentionally doing this to a bolt, as in TTY, has become more common, it results in more consistent clamping force being achieved. Harder to overdo it, as the fastener will just continue to yield. But those reusable Subaru head bolts are most certainly stretching, and the head material under the bolt head is compressing/deforming. Just not permanently. Very nice rod bolts are sometimes tightened by measuring relaxed vs installed length...measuring the stretch. But that won't work on a head bolt in a blind hole. Angle torque is a variation on that method, since a certain amount of rotation will result in a known stretch, based on the thread pitch. The angle part of the torque sequence is unaffected by friction, other than you needing to pull harder to reach the needed angle. Stretch bolt is a bad description...the only bolt that is not stretched is a loose bolt.
Does the use of "torque to yield" bolts allow the manufacturer to cheap out a bit by using a smaller part that ultimately does not have as much reserve strength ?
When I’m doing valve springs on the frs the Subaru part numbers can mix me up. I’m used to Toyota part numbers. Example is 12345-67890. The frs part numbers are like SU251AB253 for example
How long should it take a competent mechanic to pull the engine out, do the head gaskets and the rear main seal at the same time? Just wanting to make sure I am not getting ripped off
@@ernestocastro66 Not very much, temped to get my canon out and start showing people how to work on them, going to be painting mine soon been doing bodywork and such. good luck finding some though
Question time. I do lots of head gaskets on single overhead cam ej251 motors at my shop. Due to the failure of the head gaskets leaking I replace them with the mls turbo gaskets. Do I use the tightening procedure for the quad cam motor or continue to use the procedure for the single overhead cam
Honestly, not sure if it matter which procedure you use. I go by whichever procedure that model year calls for in the service manual. Haven't had an issue.
Mr. Subaru, Do you have any recommendations for aftermarket studs for the torquing of studs (Allen head studs) in block,and then torques on the nuts. 2006 2.5 DOHC Baja turbo. Learning a lot from your videos. Keep up the good work.
On my first HG job, I tried to use felpro head bolts, those things are such trash, as I was doing step 2 of the torque sequence, the bolt broke in half in the block........after I returned them I found out they were more expensive than factory bolts!..........strangely, my local subie dealer has drawers full of head bolts.....and I have seen invoices for HG jobs they've done, they do replace all 12 bolts, their techs must've bought into the stretch bolt lies too
@@MrSubaru1387 Are some of these old brand names not the quality that they used to be when they made their reputations : like back in the 1950s and 1960s ?
@@MrSubaru1387 Ok, I used the method on one of your older videos which you reuse the bolts. Does that method still work? It was the video were you show how to replace the head gasket
@@MrSubaru1387 Another question, how clean does the block surface need to be? I had the heads sent to the shop and i've been cleaning the block surface on and off for a couple days. I've used a razor, a rag with brake cleaner, and a abrasive and there is still some black/gray discoloration on the surface but it feels smooth. Does the block surface need to have a nice shiny metal color or is the discoloration fine as long as the surface is smooth?
Is there a difference when torqueing the composite gasket vs mls. Gettting ready to do heads in a non-turbo 2007 2.5, but I'm going to use the mls gaskets.
I am about to get a 2001 Subaru Outback limited version vehicle and need to replace the head gaskets. I was told that you can do that with the engine in the car but after watching a couple of videos including this one I've decided to take it to do this. Thanks for showing just how tricky it would have been - thanks for the information.
Hi wow Mr Subaru this is the go to video for us techs or DIY when doing heads I wanted to ask you how critical do you think having STIS if I was to strike out and do my own thing I still need to get a scan tool but I want to specialize in Subarus I will start very small just husling details with local Subaru owners and then see if I can do some diagnostics or engine work , How important is it to have STIS In a Subaru shop ?????? Thank you Subaru =unity NORTHERN BOXER TECHNOLOGIES (tm)
Great video! Do you by any chance know if the procedure for the EE20 diesel (2011) is the same? Both in which way to tighten/ untighten and the amount of torque required? Greetings from Norway 🇳🇴
hey i got your head gaskets and head bolts on Amazon. Thanks! Question i got confused between foot lbs and NM in the manual. So i over torqued to 69 instead of 51 before i backed them up. and 34 instead of 25 on 1 & 2...do i need to replace the head gasket and start over? I hope i didnt damage the heads!
@@MrSubaru1387 wish i had watched this video first. i believe i may have split the block or something when bottoming out #6 there was a pop. i believe i had too much oil on the bolt? im pulling my hair thinking i screwed up
Hey mr subaru again lol so I'm about to do the headgaskets on my car and ive seen a ton of different videos and forums on torque specs and if i need to get new head bolts, in my opinion your the smartest mechanic for the question on a 2010 subaru impreza ej253 should i replace all the headbolts and what are the torque specs and angles for a ej253 motor? Thanks your the best!
Mr. Subaru, my 120k miles, non-turbo 2.5 just started overheating. Ran a block test and only get combustion gasses in the radiator when the fans turn on. To me, this indicates that at a certain temperature, and only then, the problem appears. Is it possible that all I need to do is retourque the head bolts? If a head gasket is blown, it leaks at all temperatures, right? If so, can I just remove the valve covers. And do it relatively easily?
That train of thought is what led me to buy new bolts when I installed my new short block. It was more like $154 for a set of bolts but still a fraction of the thousands already put into the new motor. When I was just rebuilding heads I re-used the bolts. But with a new motor it didn’t feel right to use 15-year-old 168k-mile bolts on a new motor. I want the new motor to last another 15 years and 150k miles.
Hi, I got a 2007 subaru outback 2.5L (non turbo) I'm experiencing pressurized cooling system. Some sweating oil on the bottom back of headgaskets but not major. Looks like the coolant is not mixing with the motor oil though. I got alot going on, gotta move from Arkansas to South Dakota in the next couple of weeks, so my question is, should I hurry and replace the headgaskets, or put some kind of stop leak in and do the headgaskets after we settled in up north? If I do go with the stop leak, what is the best to use?
Good afternoon. I first time working on my Subaru legacy l. This a question I had because my alldata state u ha e to change them but the stress u putting on it is on the Aluminum at heads and block.. I'm about to do this boxer motor with out sending to a shop/pro on this. I've asked many tech and they say yes other say no.. thing is I want to fix my car right way and get less then 100k more out of that motor before a full rebuild car has 189k and I picked up for dirt cheap. My leak gasket is cylinder 4 into the water side.. and I'm running it to it get hot by then Im At the shop cool down. For a 2.5l no e turbo and don't want to use the Graph, I guess cause everyone keeps telling me.And I know of graphic guests just failing in gyms.And I knowther high rate of graphic gaskets is worthless.. we do t use that u less customer budget don't allow for the steal gasket. This where I mixed at also.. I don't mind d taking this out and doing over again but not to next year or so.. so I e been shopping around for gasket and it so funny now that they so cheaply made today.. I hear u can use the gasket from the turbo one on the 2.5. But I don't want to mod things just want to do bolt on and off I go.. I thank u for letting me know I can reuse the head bolts again and rub the bolts like we do with the arp bolts and my fear is cracking the block and is OK to put one lbs more for the center bolts at it last pass.. just want to make sure this can be done or what do u Recommend? I like this car because how simple everything is to fix or replace.. head gasket kit you Recommend? Thank u brother..
Hey Mr. subaru, by any chance do you what's the best video on RUclips for changing out my valve cover gasket on my 06 outback 2.5xt? also what gasket brand do you recommend? Thanks
I’m assuming this is all done at the factory in Japan by computer robot and probably all the head bolts at the same time I’m sure instead of individually doing them🤷🏼♂️
I just bought a 2003 Baja with bad head gaskets. To fix, I bought turbo head gaskets MLS from 2006 part number 11044AA642. Are these turbo gaskets going to be a permanent fix from your experience? Thank you.
Thanks again for sharing your knowledge with us good sir. So i have a naturally aspirated EJ25 that i'm doing the head gaskets on. While it's apart i was thinking of putting a turbo on it. I don't want to go too wild with it, cos it's a daily driver, but just wanna bring up the HP a bit. Would you still recommend doing the head stud upgrade to that?
I've been an Automotive Tech from way back in the 1980's. I have a background as a Machinist and currently work as a Technician in a hi-tech manufacturing facility. Your presentation is one of the BEST I've seen regarding TTY fasteners, Torque Angle, etc. My family has owned at least 10 Subarus over the years an still owns 3 that are 10 years old or more. All running great. You've always been a Go-To source for all things Subaru. Great job and thank you!
It was concise, on point, especially how it relates to Scoobie Doo owners and all the myths that cause many to panic and wind up spending a lot of money that they otherwise would not need to. Keep up the good work!
Wow...
You sir are a scholar and a wizard amongst auto techs!
Thank you for sharing your knowledge!
Replaced head gaskets on 2001 fozzy 5 years ago. I didn't remove the engine from car , as there was enough room . I replaced head gaskets at 182,000 , now has almost 245,000
totally not scatterbrained, actually easy to follow and understand. my confidence level to approach this job is definitely higher after watching. i just need to find a good machine shop in my area to take the heads to
Very well explained. The use of mechanical fasteners is, in general, not well understood. I began to understand years ago when torquing the 3" diameter studs on a nuclear reactor cover plate using a heater in the hollow stud, a 50-ton bridge crane to stretch the stud while the nut was screwed down hand-tight. Crane tension released, nut/stud perfectly torqued to spec, no evil stuff able to leak out the seal.
I have been following you for a while now but.... I ALWAYS learn something new (or confirm what I believed.. a tech for 38 yrs. Love Subaru. Never worked at dealership. So learned on the fly So once again thank you for teaching us and confirming things I love the videos and it's so nice to prove to somebody else that the bolts are reusable lol So many parts first say no they're not reusable...You have to buy new ones.... 😂
@Mr. Subaru, This was exceptionally well explained! Great video and am looking forward to more! Especially if they can pertain to post 2008 Foresters in the future. Thanks again for all your work in sharing your knowledge! I actually like instructional videos where you do a detailed review of aspects of previous repairs. Just as a FYI of my view... I am not as interested in tool reviews from you, although they are excellent, because those are a dime a dozen on RUclips. I come to your channel for Subaru content and Subaru content only. MUCH APPRECIATED!
Very happy to know your opinion is something I can agree with. I have done a minimum of 50 Subaru head gasket or engine jobs in private shops and never once replaced head bolts. Never ever had a premature failure. 👍👍
The general rule is if it is a 'stretch bolt' aka TTY, to toss the fastener out. Its junk after it stretches. I run ARP'S on all my stuff so I reuse them all day. Good video, nice to see someone break down the B.S. better than I can lol
i love these videos you make, i really can't wait to get a subaru
Awesome video as always. Very conclusive answer. I'm sure I'll be linking this to many misinformed people.
Too long, but subject was well-covered. Two things: To really know if the bolts might actually stretch to yield (stay elongated) you must measure the actual bolt before and after, much like you measure rod bolts when tightening. It might even be possible to strip out the threads before you get to yield, but I doubt it unless the case threads have see a lot of use or the bolt threads were bad and damaged the case threads.
Secondly, I wish you had mentioned the use of assembly lube (like ARP sells) and whether that is allowable for lubrication versus motor oil. I would think it would actually be better and give more consistent torquing due to less friction than with plain oil. The final tightening by degrees is dependent on the last torquing being accurate, even though it is a moderately low number and not a lot of friction is involved.
Thanks for making the video!
I've reused them on the 2.5l at 170000. No issues, sold vehicle at 270000.
We don't replace them unless we have a creaking issue, and even then we just grab a HB out of the bin. wire wheel threads, oil threads, moly between the washers and your good.
Not only CAN you teach an old dog new tricks, an old dog can learn from a newer dog. The fact that this video set the record Straight regarding tty bolts is actually less significant for me. The greatest part, is that this gives me hope for the younger generations.
I’ve reused my head bolts once with no problem. Make sure you use a good amount of engine oil on the threads. Assembly lube would be better.
Absolutely a good idea as long as the cavity isn't overloaded with oil, coolant, etc. You can hydro lock the threads and actually crack the part your bolting it to. Excess fluid can also throw off the torque accuracy in some instances. A dab on the threads and under the washer is all you need. It's good practice to use a blowgun to blow out all the threads to make sure one hasn't filled up with crap before you bolt it down. You hit on everything that anyone who turns a wrench should know. I actually commented on this before I even watched a minute of the video so we think alike here. Definitely touched on all the points here. 👍👍
I’ll never get anywhere near that in depth with my maintenance or repair but it’s good to know.
Great job! You answered all my questions!!! 👍👍👍 Keep doing what you do.
Thanks!
You're welcome.
Hi
When I put my machined heads on the new Subaru Short block on my 2008 Subaru Legacy GT Turbo - I was pretty nervous about this whole area and bought new head bolts. The dealership mechanic said re-use old ones. Machine shop who did the heads said I was nuts to do that - and get new ones (they won out in my mind - I got scared).
Heck, I still have the old ones.
This is most helpful to know I didnt need to do that.
Thanks!
Michael Lusk
Rule of thumb doesn’t always hurt to listen to a Subaru tech. They’ve got experience. However can’t say I blame you, there are hacks out there. Anyway hope your legacy gt is doing well. Love those cars
I'm about to do a new ej207 shortblock on my 07 legacy gt. I'm also confused if to use new head bolts or use the old ones
Mr Subaru...You are an excellent teacher and really good at explaining the details and also showing examples of doing it.
I have never owned or worked on a Subaru but your mechanic methods could apply to many applications l'm sure. I'm hooked on watching your videos and enjoy reading the comments.
Great and informative vid mate! much appreciated.
Eric O. at SMA is trying to sell a lift if you're interested. I just know you're back to the dirt and this might be an option for when you get a building sorted. Only a few states away!
Another great learning video. Less 60$ to spend on head bolts 👍👌😍😊
Thank you.
When doing h/gaskets on my 98 WRX, I found using NEVER-SEEZ,pure nickel special, anti seize compound on h/bolts. Eliminates all grabbing and gives a beautiful smooth tightening transition. Been in engineering since 1970,and swear by this stuff.
Cheers from Australia and my old REXY is still hammering!
I've reused mine on my ej22t
Hello Mr Subaru,
Great video, explaining key points on the tightening of the CH and very helpful when doing my Suby CH.
The Tensile Stress-Strain presentation was very easy to follow and on point.
Thank you for the video.
Used factory bolts are better than new aftermarket bolts. Aftermarket bolts always have dinged up threads and are never as straight as genuine bolts. If you are anal buy new bolts from the dealer, otherwise inspect your old bolts and reuse them. Subaru changed the torque sequence over and over throughout the ej engine era although they are all essentially the same. It's all bs, Subaru engineers purposely used inferior head gaskets on all of the N/A motors, knowing that they will fail at 100k. All of the turbo motors use mls gaskets that never fail because the engineers knew they wouldn't make it through the warranty period otherwise. The dohc turbo mls gaskets actually fit the sohc N/A motors, if you use these they will never leak again. Oil the bolts well, use turbo gaskets and torque bolts to 80 lb-ft and they will never leak again.
Awesome. Case closed! I spent hours researching this topic when replacing the head gaskets on my first engine. I finally settled on reusing the bolts but because of all the conflicting info I was still nervous about it. Now doing a second engine and because of this video I have 110% confidence that reusing them is fine. Thanks man!
One thing that would be interesting to know is what exactly is the difference between the corner and center bolts? Different grade steel or something? Also, why are they different in the first place? Because they're getting torqued to slightly different specs the bolts have to be different? Just curious about that...
I know it's two year too late, but I have what I believe to be an answer for you...
Imagine that we had 2 cylinders, but we keep the heads separate. You would expect 8 bolts total, since you need 4 each to hold down each head. Now imagine that we take those separate cylinders and merge them together side-by-side as close as we can. As you get them closer and closer, eventually the 4 inner most bolts would become superimposed on each other. Since objects can't occupy the same space at the same time, you would have to get rid of some bolts. Doing this you would arrive at a 6 bolt single head, as is what we see with our EJ's. What should be immediately obvious from this logic is that the 2 center bolts must necessarily be doing the work of 4 bolts if the system is to function the same as it had being separate cylinders.
TL;DR, it's a "four bolt to a cylinder" design at it's core, just the two cylinders share the center bolts for space economy efficiency reasons.
Hope that sorts things out for you, but especially anyone else reading this in the future.
Considering I found a broken factory torqued head bolt in lower cyl 4 position when I popped the heads off my ej205, I went ARP studs on the full rebuild
Clear and concise, perfect
I think what you're trying to say is that torque is only a measurement of the rotational force exerted to tighten the bolt. That's not directly measuring the actual clamping force it's putting on the head/gasket/block interface. So, since you can't directly measure that force, you just have to base it on the torque of the bolt, hence the angle measurement.
In tool & die jargen, they look like Chicago screws made to get you more movement for inaccuracies of manufactured parts. It looks like we have a new use for them.
Yaaay! I got the correct answer in your poll. Thanks for the great video.
Is there a nice to see somebody on the internet that knows what he's talking about it puts a good joke in there and makes it so I can understand what I'm doing
I've reused my EZ30 NA head bolts with no issue. I cleaned and deoiling them. Then oiled the thread. Spun on the manual with all the moments and twists. The bolt did not produce any creaks.
And I wasn't first who did that with my EZ30.
When torquing bolts on my EJ25D I gauged the torque when turning the second 90 degrees. There was on average between 78 to 80 ft*lbs.
Excellent Video learned a lot about subaru 2.5 issue thanks.
Very helpful indeed. Thank you 👍😊
2ish I've would have known that... When I ordered head gasket set it strongly recommend to replace head bolts ... Would've saved money
ShOcK & AWE outstanding Gear Head info. You R the "Subaru Whisperer" The check is in the mail.
When i young I rebuilt a ej25. Did not know to oil threads for the head bolts. Freshly rebuilt block from machine shop. Hour later it went back. As I attempted to tighten the head bolts dry😞(SNAP!!!!) broken the bolt in two
Why do you have a green screen of a dealership shop behind you?
Looks better than standing in my living room.
@@MrSubaru1387 Fair enough 👌🏼
Hey man your videos have been very informative was wondering how ypu feel about chasing the threads should help promote acurrate torque correct?
If there is any stretch I'd guess it is the AL female threads, not the steel bolts.
My wife inherited a 2012 4cyl. Outback with 50K miles. I noticed on one of your videos that you said a 2012 headgasket will eventually fail...it is just a matter of time. With that in mind, I am contemplating having the timing belt changed this summer because I have the belief that timing belts should be changed either at 80K or 8 years old. I acquired this belief from personal experience. IUO, when I have the timing belt changed, should I have the head gaskets changed too? Time and convenience are very important to me, and the expense is a tertiary concern. I would like to have your opinion.
I suppose that the ARP stud kits cost a lot more than a new set of factory head bolts (are people in the field substituting cheap new Chinese head bolts for the Factory item or are there counterfeit head bolts floating around out there ?)
I guess the ARP studs come with their proper washers and nuts?
Absolutely GREAT video!!! Answers many questions with great details and facts.
Yet I have more questions.
Does Subaru ever use Torque-To-Yield bolts?
If my Subaru has standard head bolts, are Torque-To-Yield bolts NOT recommended?
If one purchases new Torque-To-Yield bolts, would the torque sequence / process be different from the official Subaru process?
If so, where may I find the proper torque sequence / process for the Torque-To-Yield bolts?
Well I guess I'll pull out the new ones and put back the old ones! Darn could have bought some good beer! Glad I saved them.
Such a wonderful video!!! Thank you so much!!!!!!!
Great videos and very informative! I know you said we need to torque first to squish then back bolts before final torque, assuming you're using the oe single layer steel vs the Subaru uncoated MLS gasket for EJ253 SOHC NA. But is the squish step necessary for the MLS type gaskets? I've heard some subi techs skip squish step. My 02 Honda civic 1.7 SOHC NA has MLS and it didnt call for a squish and final torque step. Per your recommendation, im going to be using the mls on my subi, the design is the same as their oe single layer steel gasket. Thanks for all the help and great videos
I'm glad you asked that question. I was wondering the same thing. I've done about 4 HG jobs and i always re use my bolts and like you i don't do a squish of the HG before; i use PermaTorque MLS gaskets. In fact, i do my torque sequence a lil different. 11ft/l bs on all 6, then 25 ft/lbs on the two center bolts, then starting at the center i do 90 degree torque sequence twice. haven't had issues yet.
The squish step is neccessary; this centers and crushes the 3+ layers in the MLS gasket together prior to final torquing.
When I hear "stretch bolt", I just take it as gearhead slang for a "torque to yield " bolt, but it is a misnomer. Every tension type fastener you tighten from a tiny woodscrew to the head bolts on giant ship diesels stretches. Everything is a spring of sorts, every material has a spring rate. 10 ft lbs on a 2" diameter bolt just doesn't stretch it much.
Most bolts are tightened only within their elastic range, traditionally, and reaching the yield strength means you've permanently deformed it, it's junk.
Intentionally doing this to a bolt, as in TTY, has become more common, it results in more consistent clamping force being achieved. Harder to overdo it, as the fastener will just continue to yield.
But those reusable Subaru head bolts are most certainly stretching, and the head material under the bolt head is compressing/deforming.
Just not permanently.
Very nice rod bolts are sometimes tightened by measuring relaxed vs installed length...measuring the stretch. But that won't work on a head bolt in a blind hole.
Angle torque is a variation on that method, since a certain amount of rotation will result in a known stretch, based on the thread pitch. The angle part of the torque sequence is unaffected by friction, other than you needing to pull harder to reach the needed angle.
Stretch bolt is a bad description...the only bolt that is not stretched is a loose bolt.
Does the use of "torque to yield" bolts allow the manufacturer to cheap out a bit by using a smaller part that ultimately does not have as much reserve strength ?
When I’m doing valve springs on the frs the Subaru part numbers can mix me up. I’m used to Toyota part numbers. Example is 12345-67890. The frs part numbers are like SU251AB253 for example
How long should it take a competent mechanic to pull the engine out, do the head gaskets and the rear main seal at the same time? Just wanting to make sure I am not getting ripped off
Stock turbo application ok to reuse. Im not adding any horsepower.
Just bought a SVX, Would love some content, also if you have any fenders laying around...
Did you find any SVX content? My son bought a SVX..
@@ernestocastro66 Not very much, temped to get my canon out and start showing people how to work on them, going to be painting mine soon been doing bodywork and such. good luck finding some though
@@kopboy55 I found a couple people working on their SVX on RUclips .. someone on RUclips shared all the service manuals!
Hello grateful info one question what if you mix the bolt are there any differents
Great info thanks for sharing!
Does it matter what kind of oil you use on the bolt? So just a thin layer on the spots you said?
What's the best seal kit I can use for a turbo subaru?
Question time. I do lots of head gaskets on single overhead cam ej251 motors at my shop. Due to the failure of the head gaskets leaking I replace them with the mls turbo gaskets. Do I use the tightening procedure for the quad cam motor or continue to use the procedure for the single overhead cam
Honestly, not sure if it matter which procedure you use. I go by whichever procedure that model year calls for in the service manual. Haven't had an issue.
@@MrSubaru1387 thanks. Do you also go the mls gaskets over the standed one?
@@jamesedmondson7265 100%. I only use the MLS gaskets
Mr. Subaru,
Do you have any recommendations for aftermarket studs for the torquing of studs (Allen head studs) in block,and then torques on the nuts. 2006 2.5 DOHC Baja turbo. Learning a lot from your videos. Keep up the good work.
Never mind. Should have watched the complete video 😂
But where can I find a service manual for my subaru? Please...
Jdmfsm.info
Thank you for this question, and the other you, for the answer!
Same torque specs for turbo cars?
Would it be cheap insurance to replace the bolts anyway? They can't be that expensive
On my first HG job, I tried to use felpro head bolts, those things are such trash, as I was doing step 2 of the torque sequence, the bolt broke in half in the block........after I returned them I found out they were more expensive than factory bolts!..........strangely, my local subie dealer has drawers full of head bolts.....and I have seen invoices for HG jobs they've done, they do replace all 12 bolts, their techs must've bought into the stretch bolt lies too
You aren't the first to tell me they snapped a Fel-Pro head bolt off. OE bolts are the only way to go.
I snapped 2 fel pro bolts off on my first head gasket job. Oem bolts ever since(when they actually need replacement).
Fail-Pro head bolts have a reputation for breaking on install. Straight garbage..
@@MrSubaru1387 Are some of these old brand names not the quality that they used to be when they made their reputations : like back in the 1950s and 1960s ?
@@davidpowell3347 absolutely not. They’re manufacturing in the 3rd world now to the lowest bidder.
You mentioned "lint" a few times, unless I misunderstood. What are you referring to?
do the dowels need to be replaced?
The sequence at 10:24 is for new bolts correct and not for reusing old bolts?
Both.
@@MrSubaru1387 Ok, I used the method on one of your older videos which you reuse the bolts. Does that method still work? It was the video were you show how to replace the head gasket
@@b33fcake34 yes. Done it that way many times as well.
@@MrSubaru1387 ok thank you, just needed to make sure I did it right.
@@MrSubaru1387 Another question, how clean does the block surface need to be? I had the heads sent to the shop and i've been cleaning the block surface on and off for a couple days. I've used a razor, a rag with brake cleaner, and a abrasive and there is still some black/gray discoloration on the surface but it feels smooth. Does the block surface need to have a nice shiny metal color or is the discoloration fine as long as the surface is smooth?
one and done on boosted applications save yourself the headache and get arp studs
What about light coat copper anti seize over oil coating?
I torked mine to 50 ft than to 75 on outer and 80 on inter bolts.
Muy Buena explicacion
Is there a difference when torqueing the composite gasket vs mls. Gettting ready to do heads in a non-turbo 2007 2.5, but I'm going to use the mls gaskets.
what about the case bolts?
I am about to get a 2001 Subaru Outback limited version vehicle and need to replace the head gaskets. I was told that you can do that with the engine in the car but after watching a couple of videos including this one I've decided to take it to do this. Thanks for showing just how tricky it would have been - thanks for the information.
Thanks for this video so just want to check that it's ok for the EJ 25 engine head bolts to be reused as well? thx
Hi wow Mr Subaru this is the go to video for us techs or DIY when doing heads I wanted to ask you how critical do you think having STIS if I was to strike out and do my own thing I still need to get a scan tool but I want to specialize in Subarus I will start very small just husling details with local Subaru owners and then see if I can do some diagnostics or engine work , How important is it to have STIS In a Subaru shop ?????? Thank you Subaru =unity NORTHERN BOXER TECHNOLOGIES (tm)
How do I tell which side of the gasket goes which direction on the Subaru mls gasket?
Although your information is true, I still always replace the head bolts when replacing a head gasket.
Great video! Do you by any chance know if the procedure for the EE20 diesel (2011) is the same? Both in which way to tighten/ untighten and the amount of torque required? Greetings from Norway 🇳🇴
hey i got your head gaskets and head bolts on Amazon. Thanks! Question i got confused between foot lbs and NM in the manual. So i over torqued to 69 instead of 51 before i backed them up. and 34 instead of 25 on 1 & 2...do i need to replace the head gasket and start over? I hope i didnt damage the heads!
You should be OK. If you pull it apart, you'll have to install new head gaskets.
@@MrSubaru1387 wish i had watched this video first. i believe i may have split the block or something when bottoming out #6 there was a pop. i believe i had too much oil on the bolt? im pulling my hair thinking i screwed up
Two of my bolts sh9ow surface rust on the shaft, do I need to replace?
Odd to see rusting on them. Likely would replace with a Subaru genuine bolt. Aftermarket bolts are a no-go.
Do you have a EJ25 DOHC head gasket replacement video?
I do.
Hey mr subaru again lol so I'm about to do the headgaskets on my car and ive seen a ton of different videos and forums on torque specs and if i need to get new head bolts, in my opinion your the smartest mechanic for the question on a 2010 subaru impreza ej253 should i replace all the headbolts and what are the torque specs and angles for a ej253 motor? Thanks your the best!
Jesus christ man watch the video
Mr. Subaru, my 120k miles, non-turbo 2.5 just started overheating. Ran a block test and only get combustion gasses in the radiator when the fans turn on. To me, this indicates that at a certain temperature, and only then, the problem appears. Is it possible that all I need to do is retourque the head bolts? If a head gasket is blown, it leaks at all temperatures, right? If so, can I just remove the valve covers. And do it relatively easily?
What about ARP head studs? Does ARP make head studs for Subaru? Is that a better option?
I talked about ARP head studs at the end of the video.
@@MrSubaru1387 Yeah I just noticed that sorry. I made the comment before the video was over. Ha Ha!!!
Sure you CAN reuse them, but what's the point when something that important is at stake and you can get new head bolt set for 40 bucks?
That train of thought is what led me to buy new bolts when I installed my new short block. It was more like $154 for a set of bolts but still a fraction of the thousands already put into the new motor. When I was just rebuilding heads I re-used the bolts. But with a new motor it didn’t feel right to use 15-year-old 168k-mile bolts on a new motor. I want the new motor to last another 15 years and 150k miles.
hows it going man, may i ask if i need a new headgasket if i am replacing my headstuds and bolts with an aftermarket, sorry for the dumb question
Hi, I got a 2007 subaru outback 2.5L (non turbo) I'm experiencing pressurized cooling system. Some sweating oil on the bottom back of headgaskets but not major. Looks like the coolant is not mixing with the motor oil though. I got alot going on, gotta move from Arkansas to South Dakota in the next couple of weeks, so my question is, should I hurry and replace the headgaskets, or put some kind of stop leak in and do the headgaskets after we settled in up north? If I do go with the stop leak, what is the best to use?
Good afternoon. I first time working on my Subaru legacy l. This a question I had because my alldata state u ha e to change them but the stress u putting on it is on the Aluminum at heads and block.. I'm about to do this boxer motor with out sending to a shop/pro on this. I've asked many tech and they say yes other say no.. thing is I want to fix my car right way and get less then 100k more out of that motor before a full rebuild car has 189k and I picked up for dirt cheap. My leak gasket is cylinder 4 into the water side.. and I'm running it to it get hot by then Im At the shop cool down. For a 2.5l no e turbo and don't want to use the Graph, I guess cause everyone keeps telling me.And I know of graphic guests just failing in gyms.And I knowther high rate of graphic gaskets is worthless.. we do t use that u less customer budget don't allow for the steal gasket. This where I mixed at also.. I don't mind d taking this out and doing over again but not to next year or so.. so I e been shopping around for gasket and it so funny now that they so cheaply made today.. I hear u can use the gasket from the turbo one on the 2.5. But I don't want to mod things just want to do bolt on and off I go.. I thank u for letting me know I can reuse the head bolts again and rub the bolts like we do with the arp bolts and my fear is cracking the block and is OK to put one lbs more for the center bolts at it last pass.. just want to make sure this can be done or what do u Recommend? I like this car because how simple everything is to fix or replace.. head gasket kit you Recommend? Thank u brother..
Hey Mr. subaru, by any chance do you what's the best video on RUclips for changing out my valve cover gasket on my 06 outback 2.5xt? also what gasket brand do you recommend? Thanks
Subaru OE. They're priced just about the same as aftermarket. Can't recall if I have a cam cover gasket video on the DOHC engines or not...
I’m assuming this is all done at the factory in Japan by computer robot and probably all the head bolts at the same time I’m sure instead of individually doing them🤷🏼♂️
I just bought a 2003 Baja with bad head gaskets. To fix, I bought turbo head gaskets MLS from 2006 part number 11044AA642. Are these turbo gaskets going to be a permanent fix from your experience? Thank you.
can i use shellac on head gasket?
No..
Would this sequence work for a 2017 wrx sti?
Hello I've noticed on the ej2.0 turbo, some say 27ft lbs on 1 and 2 bolts and 14ft lbs on 3, 4 5 6. before doing the 80 to 90 twice. is this correct?
*to much lught for the green screen. is making your beard green :) Thx for the info ;)
Is it safe to buy a 15 year old Subaru Legacy Outback with a 3.0 r
Should I replace my stock studs and bolts that hold my jpipe to the turbo on my 2020 wrx when replacing it with a cobb jpipe? It only has 16k miles.
Thanks again for sharing your knowledge with us good sir. So i have a naturally aspirated EJ25 that i'm doing the head gaskets on. While it's apart i was thinking of putting a turbo on it. I don't want to go too wild with it, cos it's a daily driver, but just wanna bring up the HP a bit. Would you still recommend doing the head stud upgrade to that?