Came to learn the difference between interference and non interference engines and felt like I am leaving with so much more . This is an incredibly underrated channel and I really hope you get the views you deserve sooner more than later! thank you! like and subbed.
Many thanks. Anyone can pretty much take these repairs on with some direction and a few tools. I appreciate you still stopping by and for watching the videos. Make sure to subscribe and click that bell icon as well.
Wonderful job! I love this. I keep promoting your video on the facebook PT forums. Too many people want to drive it until it breaks because it is "non-interference". They're so wrong.
It don't matter if it's interference or non-interference. When you're getting down the road at 60 70 80 mph and the belt or the chain comes loose something is bound to smack they're not like the old engines back in the day. These engines have no tolerance for mistake hopefully you will not learn that the hard way on your own vehicle
I have NEVER heard of valve to valve interference until this video. It makes sense now but I think in this specific case you're correct. There is just no way they hit each other unless the lash is WAY out of spec. So far out that the valve can't completely close; or put another way, NO LASH AT ALL. Which would cause problems way before the belt breaks.
This is an outstanding video, and part of an outstanding series, that resolved a long standing question about the 2.4 liter twin cam. You did a great job of forensic engineering, that never would have been needed if those diploma engineers had properly insisted on exhaust valve reliefs at the tops of the piston crowns. That would have only reduced the compression about one, or at most two, percent and saved a lot of trouble for a lot of people. Thanks again.
MAny companies are installing 4 valves for each cylinder. You only need 2 valves per cylinder. 1 intake @ 1 exhaust. You are asking for trouble with 4.
Nice work, I agree that if you have a problem with something that you should check it out for yourself and see what the problem is and why it is happening, and seeing it with your own eyes is priceless as far as solving the issue. I also like how you did not have a problem with admitting you may or may not have been correct and explained it, too many people would just sweep it under the rug or blame somebody or something else and hope nobody says anything, and move onto something else. Subbed
Many thanks for subscribing and for checking the video out. I am one of those people that like to see it for myself. For one its easier for me to grasp. I can admit that I am not perfect for sure and there is always room for learning and for improvement on my end. I certainly havent seen it all and each day I come across at least one thing I was wrong about or that I didnt know. Thanks again for watching!
Dude, thank you!! This video helped me, a NOVICE at BEST, more than any input I've gotten from multiple mechanic buddies of mine over the last few weeks.. You are the friggin man!!! I'm so stoked, thanks again, bro. Keep rockin', Legend!
Man, we all learn something new eventually. I been wrenching on cars my entire life, and stilllearn new things from time to time. You are good mechanic.
As the original owner of a 1989 Dodge Spirit ES turbo car AND the factory issued shop manual for the car, I can tell you from my own wrenching experience over all these years, a corporation can and sometimes does make mistakes in their printed literature about their own product. It's not often, but it does happen. BTW, the 2.5L SOHC engine in the Spirit is virtually all original except for 5 head gaskets, one timing belt, and a valve grind. Over 300K miles now. Love your channel David. Hope you keep it going for many more years.
Good explanation Sir. I learned that VWs and Nissan motors are interfering engine. That is why it is important to Install a New Serpentine belt at about 60 thousand miles as a preventable measure. I would never own a interfering engine especially after learning all the different ways this event can happen. Thanks for Educating the Serious DIY's...👍👍
The coments about my engine (93 Ford Ranger 2.3) being non interference on another video brought me here and I learned something new plus Im glad mine is a none Interference. Thanks, great video and subscribed.
...WOW !!! ...I like the way you explained the difference between the two !!! ... Keep on sharing, you are awesome instructor ;) ;) ;) ....From state of Florida
I really find it astounding that Chrysler's service bulletin was wrong on this issue. That's a fundamentally gross error. You're not wrong to believe mostly all of the service bulletins, notices, etc. that are released by the major auto manufacturers. Errors are rare, yet they do happen. Step by step analysis is still your best tool. I enjoy your videos and your teaching style. Thorough without boring this old shade tree mechanic. Keep up the good work.
Errors are unfortunately rather common in automotive service publications because they are written by engineers who rely too much on theoretical and inflexible modes of knowledge. In reality, common sense and experience are often far better guides when dealing with mechanical realities than a whole lot of gobbledegook aimed at addressing endless possibilities.
Many many thanks. Growth is always welcome. I seemed to be toooo laser focused to the brand that I know that it limits who comes to the channel. Appreciate the kind words and the support. Merry Christmas
@@MotorCityMechanic I was going to ask if you're jealous of guys who work on Hondas and Toyotas in a playful way. I'm sure as a mechanic their all the same with minor differences.
No brand is perfect and each has its common issues. I hear more from previous Ford techs about all their issues then any other. I’m mainly just brain washed with the brand I have worked on for 30 years
@@CTSCAPER 30 years lol.....I meant 20. Most times I know where to jump to first when checking them out. Thats one reason I prefer working at the dealership.
From the title, was expecting an explanation for non-interference engine instead of discussion of this particular Chrysler engine whether its non-interference engine or not... But either way, this video gave bit more extra information.
Many thanks. I like to include as much as I can from time to time....sometimes I dont have whats needed on hand but when I do I try to add it. I appreciate the kind words and feedback. Make sure to subscribe.
Wishing you was my neighbor!!! Love your videos and if your looking for ideas on video content, 3rd gen 6.7 Cummins seems to be popular lol take care David and have yourself a very merry Christmas!!!
thank you for the info nice job explaining it i just had a volvo engine interferance type and the water pump seized and the belt jumped and i cranked the engine becuse i was on a set of RR tracks with a train heading toward me when i pulled the head i had valve to piston contac and you could see the damage valves not seating but it only cost me bout 5 benjamins did the removal and replacement and had a machine shop mill the head and do a complete valve job well worth the money and i enjoyed doing it thanks again for sharing info
When you do it yourself you save alot of money. I like doing jobs like these when I have no time limits and not in a rush for sure. Thanks for telling me your story and for watching my video. Make sure to subscribe.
Now I'm worried! My '06 Cruiser has a broken belt and I was hoping to NOT have to remove the head. At least now I'll do some thorough checking before I button it all back together. THANKS for another excellent video! KUDOS again to you!!!
I havent seen one bend the valves when the belt broke, mainly when someone did something wrong like on this vehicle. I feel you will be fine. Thanks for watching and for the question. Merry Christmas Tom!
@@MotorCityMechanic yep, Ive been thinking about that too. Those witness marks on the pistons look more like over-revving to me. Think that's possible? If you've already repaired it what did you find? Were the valves only slightly bent? Just curious. Thanks! Tom
@@tomferguson4996 It appears only slightly bent. I have a new set of exhaust valves that I need to get around to installing when ever I get some free time.
Stumbled upon this video because I wanted to know about interference engines (I'm still not sure if my 2004 Toyota Camry V6 is interference or non-interference, I keep getting conflicting info) and you helped explain to me what that concept means. You made it easy to understand even from a non-gearhead's point of view. This also goes to show why Chrysler gets its reputation as it does - it just seems like "good engineering" wasn't a term in design. They make slick looking cars but they always have these strange faults. A non-interference engine but the valves can still smash into each other, but they're wrong about it? Might as well just should've just added "Yeah, we're stupid" at the end of that service manual blurb.
Thanks. Those dents in the piston almost look like they fit the bottom side (radius) of the exhaust valve head, more perfectly than the top side like you demonstrated. As you showed, the leak down test told the story. When you found the factory cam alignment holes were off, I personally would have been tempted to loosen the exhaust cam sprocket bolt, align the cams using the factory alignment holes, retorque the exhaust sprocket bolt do the leak down test and then see if the engine would then start/run. Regardless, once you found the exhaust valves were leaking, you knew you were going to have to pull the head to fix all that was wrong (and do some preventative repairs while you were in there). You are obviously a very good technician and teacher, thanks for making the videos!!! It's an Excellent series, I've shared them with my son and brother that own PT's.
Really nice to watch a video by someone who knows their stuff vs some of these videos out there where they just want to show off all their snap on tools. I admire the detail you put in you work. Question: Are you mostly self taught and always just loved working on cars or did you go through a lot of training to get where you are ? Again, great videos David !
Thanks for understanding my process. I have been at the same dealer for going on 21 years now.....I like to think I am mechanically inclined and like most of you....just need the info for me to do the repair. Much like fixing the washer or dryer at the house or the a/c unit or even the plasma TV. If I have the info....I can take the task on. Its all bout finding the knowledge from somewhere. I have worked on cars one way or another since I was 16 so its pretty much my life I guess.....I wouldnt say that I love it, its more of a saving money and fixing it myself thing. I never run outside happy to work on anything lol. I like the money and I can do this job so it works well together lol. Thanks for reaching out and make sure to subscribe Ron if you havent already
Great information and descriptive learning Dave. Valve to valve contact was a prominent issue in early multi valve overhead cam diesel engines with primate electronic injection, where the early belts or chains failed, especially in Australia where extreme heat, multi trailer combos are prominent. In all engines failures I've diagnosed with this description, the valves had not touched the pistons, due to the volumetic concaved pistons (increased volumetric area), but had edge contact with the opposing bank, resulting in major valve head degregation, from chips to complete severance. Other diagnosis of terminal failure include exhaust valve failure due to Jake Brake failing to release after disengagement, Hobbs switched fans causing belts/chains to jump a notch when engaging due to failure of soft start mechanism affecting cam timing, early ECU failures, most notably on Euro trucks with primitive VVT, losing sensor activity, suddenly engaging limp home without warning, and regarding the timing without confirmation of either cam / valve positioning. Add the failure of belts due to atmosphere and mechanical exposure, and overstressed timing chains, and you have very expensive repairs as the engines were usually destroyed by shrapnel from valves and / or disintegrating turbo turbines. Oh....one funny issue seemingly encountered on industrial Detroit diesels was the engines would fall out of timing without warning for no obvious reason but never damaged valves. When the heads were removed exposing the combustion chamber, the valves, usually inlet, had caught the edge of the exhaust valve, rendering retraction impossible. 👍👍
My friend had PT cruiser i warned him about changing the timing belt but it broke and the exhaust valves were badly damaged the pistons hit the exhaust valves
Great explanation Dave. Like you, Chrysler made it more difficult to understand and we all learned something about valve to valve vs valve to piston clearance.
always told to never" assume" because it will make an ( "ass" out of "U" and "me"). How can we now take the manufactures bulletins as always being true after what you proved. Love your presentation and your method of analyzing each step. Please keep the videos coming and thanks for your time.
Thanks Brian! Your right about assuming lol. I only believe what I see for the most part. Its rare that I dont agree with the service info. You keep watching and I will keep making videos when ever I can.
I am surprised as well about the no thumbs downs......I know that now that I said that they will start showing up lol. Thanks for watching and Merry Christmas!
And the reason I came across your video is because I was looking to see if a 1995 Honda 1.8 engine is a "clearance" or "interference" engine. Would you happen to know? I recall there was a list of all engines listing the ones that hit and the ones that don't hit when the timing belt/chain breaks but I can't locate it :( Thank you for your time making these videos it is much appreciated 👍🏻
Morning. I havent ever worked on a Honda so I dont know for sure. I dont trust what is written as you saw in the video. I good Honda tech would know for sure but I dont know of any. Guess I am of no real help when it comes to that vehicle. Thanks for watching and for following the channel.
Awesome video brotha 👍🏻 I'm surprised in all your years of wrenching you've never heard about valve to valve contact possiblitys, we learn something new everyday right. But anyway my question is have you thought about notifying Chrysler of your findings of this situation? I wouldn't be surprised if they wanted to hire you on as an engine designer (for real) you definitely know your shit. I've been a mechanic at a Chrysler/Plymouth/Jeep dealership for 13 years so I can tell you got skills 🔧
To be honest I never even thought about the valves either. Just over looked it I suppose. I appreciate the kind words coming from a fellow tech....means alot.
Great video! As an owner of two Chrysler vehicles with the 2.4, this is very useful info. I changed the belt on both mine at the suggested interval, and now I can see that I am glad I did. The exhaust valves did come into contact with the piston. Did you have to replace the piston in this case? Is this discussed in a later video?
Piston was okay and I didnt seen the need. No issues with it running lol. If the belt breaks your okay....its just when someone times it up wrong or does something like in my case with the cam shaft alignment pin. Thanks for watching Kirk and for the comments.
David, Have you ever heard of a 97 3.5L break a timing belt and not have bent valves? My belt broke while idling at a stoplight ,now worried my intrepid is junk. Excellent video ! Had to subscribe to your channel!
On the older 3.5 you should be fine. We replaced them all the time back then with locked up waterpumps and broken belts. Over time the newer versions of that engine would bend valves.
That was super clear!! It is an interference engine. Congrats on the twins!! On 2016 T&C, would u take the door off when changing door lock actuator, or would u fight it with the door on? Thank u David!!
Very informative. I have 2011 equinox with 2.4 interference eng w/81K, Unaware plastic chain guide broke tried to start engine which may added to damaged valves. Having new crate engine installed ($$$). So as to understand all this, you say that pistons on non interference engines can over extend and hit valves and not visa versa? Are all DOHC engines considered interference? When looking for a new car, interference/non-interference engines never come to mind. Thanks
Funny you would say that.....we have one of those in the shop right now for that exact same issue. Seems to be common. When it comes to engines.....each is different. Some are and some arent interference. The Chrysler 3.5 use to not be.....but the later versions were. Its all about the internal make up and there is no one rule that fits them all. Thanks for asking and make sure to subscribe.
Is there a possibility that the factory measurements were correct, at the exception that they forgot to take in count the EXPANSION of the metal due to TEMPERATURE ? In short, is the extension different when the motor is cold and when the motor is hot ? Anyway, GREAT GREAT VIDEO ! Many thanks ! Keep on the good work.
Another item brought up is if the head has been shaved previously. There are always a few items that you over look and dont factor in like in this case. Multiple possibilities. Thanks for watching and for the comment!
Nice video. I just bought a Honda generator (EG2800i) that I LATER found out needed a timing belt replacement after every 250 hrs. I specifically asked about the potential "interference" issue and all I got was ...... [crickets]. The service department didn't even know what I was talking about. Regarding the PT you were working on, when you put the valves back in and cycled the valve train manually, @13:05 you mentioned the momentum of the opening exhaust valves possibly being enough to throw them into contact with the piston. . You've no doubt heard of "valve float" and that happens when the spring rate doesn't allow the lifter to keep up with the profile of the cam lobe, especially at high revolutions, and that may introduce a wear depression where the trailing ramp of the cam meets the base circle. 50 years ago, you'd see it occasionally. Today? I dunno Have you had reason to suspect the valve spring compression? I once overhauled a Divco milk truck that had a 6-cyl flathead 225?cuin Hercules QXD engine that put out a whopping 65 horsepower. I could fully depress the brand new valve springs in my hand. Just sayin'.
I have an '04 PT GT (Turbo HO). I have seen conflicting info on this topic and have wondered if it was an interference engine or not. Now I know, thinks. Great videos!!! In caution I replace the timing belt at 75k.
Have seen damage from piston to valve more than once on "non-interference" engines from multiple makes. Don't forget to remove any of the sharp areas the impact points have. Don't want a hot spot to create an issue.
The service info is assuming the belt is on timing, if it jumps of course it can hit the piston, especially that engine where the piston is above the top of the block.
These videos are awesome. Is it possible that resurfacing of the head reduced the clearance enough to allow the exhaust valves to interfere with the piston?
On some vehicles it sure can.....plus you might not know that it was shaved already before and not its getting done again. I would assume a machine shop would be able to tell if it has. Thanks for the question and make sure to subscribe.
I like how even when he was right to begin he still explained thoroughly how he could be wrong that’s mad respectable
Thanks for the feedback….it’s always appreciated and welcomed
I'm not a mechanic but that's about as clear as any professional could have given that thank you I appreciate your time
Many thanks for that awesome feedback! Make sure to subscribe if you havent already.
Outstanding explanation, I think you covered everything, and I don’t see a need in recreating the other video that you are contemplating a redo on.
Appreciate the comment Jeremy! Thanks for the feedback as well.
Came to learn the difference between interference and non interference engines and felt like I am leaving with so much more . This is an incredibly underrated channel and I really hope you get the views you deserve sooner more than later! thank you! like and subbed.
Thanks for the kind words
I have nothing to do with cars or engines but your video and analysis was brilliant David
Many thanks. Anyone can pretty much take these repairs on with some direction and a few tools. I appreciate you still stopping by and for watching the videos. Make sure to subscribe and click that bell icon as well.
well done -- we need more mechanics like you
Many thanks for those very kind words!
"Never assume" has served me well in my 58 years. Always learning thanks brother!
I fully agree…I learn something new almost everyday when working on these vehicles
Another case of the engineers saying; "That's not supposed to happen."
Very true
it's great when a non engineer can question what's written on the book. GREAT WORK!!
Thanks for commenting and for watching Ricardo! Make sure to subscribe.
This is what confused me to no end. Thank you for clarifying this. Off to the machine shop I go.
I like the moral of this story. Never believe what you read but to check it yourself instead.
Very true! Thanks for watching and for commenting. Make sure to subscribe.
Wonderful job! I love this. I keep promoting your video on the facebook PT forums. Too many people want to drive it until it breaks because it is "non-interference". They're so wrong.
It don't matter if it's interference or non-interference. When you're getting down the road at 60 70 80 mph and the belt or the chain comes loose something is bound to smack they're not like the old engines back in the day. These engines have no tolerance for mistake hopefully you will not learn that the hard way on your own vehicle
I have NEVER heard of valve to valve interference until this video. It makes sense now but I think in this specific case you're correct. There is just no way they hit each other unless the lash is WAY out of spec. So far out that the valve can't completely close; or put another way, NO LASH AT ALL. Which would cause problems way before the belt breaks.
This is an outstanding video, and part of an outstanding series, that resolved a long standing question about the 2.4 liter twin cam.
You did a great job of forensic engineering, that never would have been needed if those diploma engineers had properly insisted on exhaust valve reliefs at the tops of the piston crowns. That would have only reduced the compression about one, or at most two, percent and saved a lot of trouble for a lot of people.
Thanks again.
MAny companies are installing 4 valves for each cylinder. You only need 2 valves per cylinder. 1 intake @ 1 exhaust. You are asking for trouble with 4.
1 Cam @ 2 valves per cylinder. The old slant six cylinder would go a long way.
Nice work, I agree that if you have a problem with something that you should check it out for yourself and see what the problem is and why it is happening, and seeing it with your own eyes is priceless as far as solving the issue. I also like how you did not have a problem with admitting you may or may not have been correct and explained it, too many people would just sweep it under the rug or blame somebody or something else and hope nobody says anything, and move onto something else. Subbed
Many thanks for subscribing and for checking the video out. I am one of those people that like to see it for myself. For one its easier for me to grasp. I can admit that I am not perfect for sure and there is always room for learning and for improvement on my end. I certainly havent seen it all and each day I come across at least one thing I was wrong about or that I didnt know. Thanks again for watching!
Dude, thank you!! This video helped me, a NOVICE at BEST, more than any input I've gotten from multiple mechanic buddies of mine over the last few weeks.. You are the friggin man!!! I'm so stoked, thanks again, bro. Keep rockin', Legend!
Excellent video. Your honesty and self-accountability is to be admired.
Never assume. Test, test, test!
Man, we all learn something new eventually. I been wrenching on cars my entire life, and stilllearn new things from time to time. You are good mechanic.
Outstanding explanation! God bless America🇺🇸
As the original owner of a 1989 Dodge Spirit ES turbo car AND the factory issued shop manual for the car, I can tell you from my own wrenching experience over all these years, a corporation can and sometimes does make mistakes in their printed literature about their own product. It's not often, but it does happen. BTW, the 2.5L SOHC engine in the Spirit is virtually all original except for 5 head gaskets, one timing belt, and a valve grind. Over 300K miles now. Love your channel David. Hope you keep it going for many more years.
Your videos are great on the PT I have a 2004 with 202,680 miles on it
Thanks man! The feedback is greatly appreciated
Awesome brother! Just bought a base PT and you will be my go to guy on these 2.4L engines. 👍
Good explanation Sir. I learned that VWs and Nissan motors are interfering engine. That is why it is important to Install a New Serpentine belt at about 60 thousand miles as a preventable measure. I would never own a interfering engine especially after learning all the different ways this event can happen. Thanks for Educating the Serious DIY's...👍👍
Thanks for a thorough discussion.
Your welcome. Thanks for watching!
David, always a pleasure to see you upload a video! I hope this means we get to see a head rebuild video soon 😏
Looks like it lol. Eventually when I can find the time and work it in. Waiting on a few more parts and then I should be good to go.
probably the clearest and most technically superb video Ive seen on this issue.
The coments about my engine (93 Ford Ranger 2.3) being non interference on another video brought me here and I learned something new plus Im glad mine is a none Interference. Thanks, great video and subscribed.
Many thanks. Always glad to see people watching my videos and glad that they find them helpful. I appreciate the subscribe as well!
I have been following this series, This video just made me subscribe. Excellent job!
Many thanks Man! Both for watching and for subscribing.
Tanks for this video I have this problem for long time diesel drips damage started I start tomorrow to fixed my truck tanks
...WOW !!! ...I like the way you explained the difference between the two !!! ... Keep on sharing, you are awesome instructor ;) ;) ;) ....From state of Florida
Many thanks Ben for the kind words! Make sure to subscribe if you havent already
I really find it astounding that Chrysler's service bulletin was wrong on this issue. That's a fundamentally gross error. You're not wrong to believe mostly all of the service bulletins, notices, etc. that are released by the major auto manufacturers. Errors are rare, yet they do happen. Step by step analysis is still your best tool. I enjoy your videos and your teaching style. Thorough without boring this old shade tree mechanic. Keep up the good work.
Many thanks Don! Appreciate the comment and for your time spent watching
Errors are unfortunately rather common in automotive service publications because they are written by engineers who rely too much on theoretical and inflexible modes of knowledge. In reality, common sense and experience are often far better guides when dealing with mechanical realities than a whole lot of gobbledegook aimed at addressing endless possibilities.
Great stuff. I hope your channel starts getting the views it deserves. Your videos are as thorough as I've seen regarding automotive repairs.
Many many thanks. Growth is always welcome. I seemed to be toooo laser focused to the brand that I know that it limits who comes to the channel. Appreciate the kind words and the support. Merry Christmas
@@MotorCityMechanic I was going to ask if you're jealous of guys who work on Hondas and Toyotas in a playful way. I'm sure as a mechanic their all the same with minor differences.
No brand is perfect and each has its common issues. I hear more from previous Ford techs about all their issues then any other. I’m mainly just brain washed with the brand I have worked on for 30 years
@@MotorCityMechanic That makes sense. I guess you know what to look for first when something goes wrong with a Chrysler. Keep up the great videos!
@@CTSCAPER 30 years lol.....I meant 20. Most times I know where to jump to first when checking them out. Thats one reason I prefer working at the dealership.
From the title, was expecting an explanation for non-interference engine instead of discussion of this particular Chrysler engine whether its non-interference engine or not...
But either way, this video gave bit more extra information.
Thanks for watching and for the feedback. Its much appreciated
@@MotorCityMechanic
👍
You are a very owhnest and professional clever Mechanic
Wow! You have explained this in such good detail with actual real life examples.
Many thanks. I like to include as much as I can from time to time....sometimes I dont have whats needed on hand but when I do I try to add it. I appreciate the kind words and feedback. Make sure to subscribe.
From all the videos out there you are the best.
Many thanks! I appreciate the kind words. Make sure to subscribe if you havent already.
Another Great video.
I believe you, more than Chrysler.
Thanks David.
Many thanks for watching and for having faith in me.
Wishing you was my neighbor!!! Love your videos and if your looking for ideas on video content, 3rd gen 6.7 Cummins seems to be popular lol take care David and have yourself a very merry Christmas!!!
Many thanks man! I will certainly keep that in mind. Merry Christmas to you and yours as well!
Excellent video. Thanks for putting such great content out. Keep the Pentastar 3.6L videos coming! 🤘🏽
Thanks for watching all the videos and for commenting. I will make sure to mix a few in there from time to time
thank you for the info nice job explaining it i just had a volvo engine interferance type and the water pump seized and the belt jumped and i cranked the engine becuse i was on a set of RR tracks with a train heading toward me when i pulled the head i had valve to piston contac and you could see the damage valves not seating but it only cost me bout 5 benjamins did the removal and replacement and had a machine shop mill the head and do a complete valve job well worth the money and i enjoyed doing it thanks again for sharing info
When you do it yourself you save alot of money. I like doing jobs like these when I have no time limits and not in a rush for sure. Thanks for telling me your story and for watching my video. Make sure to subscribe.
Now I'm worried! My '06 Cruiser has a broken belt and I was hoping to NOT have to remove the head. At least now I'll do some thorough checking before I button it all back together. THANKS for another excellent video! KUDOS again to you!!!
I havent seen one bend the valves when the belt broke, mainly when someone did something wrong like on this vehicle. I feel you will be fine. Thanks for watching and for the question. Merry Christmas Tom!
@@MotorCityMechanic yep, Ive been thinking about that too. Those witness marks on the pistons look more like over-revving to me. Think that's possible? If you've already repaired it what did you find? Were the valves only slightly bent? Just curious.
Thanks!
Tom
@@tomferguson4996 It appears only slightly bent. I have a new set of exhaust valves that I need to get around to installing when ever I get some free time.
Another great video David. Love the content. How many times I've read incorrectly printed technical information Chrysler....I have lost count.
Thanks Timothy! Appreciate it man,
Again a great video. Technicians such as you are Golden.
Thanks Terry. The kind words are appreciated
U the man
Excellent video! Thanks for the explanation.
Stumbled upon this video because I wanted to know about interference engines (I'm still not sure if my 2004 Toyota Camry V6 is interference or non-interference, I keep getting conflicting info) and you helped explain to me what that concept means. You made it easy to understand even from a non-gearhead's point of view.
This also goes to show why Chrysler gets its reputation as it does - it just seems like "good engineering" wasn't a term in design. They make slick looking cars but they always have these strange faults. A non-interference engine but the valves can still smash into each other, but they're wrong about it? Might as well just should've just added "Yeah, we're stupid" at the end of that service manual blurb.
Great video man this taught me a lot
Thanks. Those dents in the piston almost look like they fit the bottom side (radius) of the exhaust valve head, more perfectly than the top side like you demonstrated. As you showed, the leak down test told the story. When you found the factory cam alignment holes were off, I personally would have been tempted to loosen the exhaust cam sprocket bolt, align the cams using the factory alignment holes, retorque the exhaust sprocket bolt do the leak down test and then see if the engine would then start/run. Regardless, once you found the exhaust valves were leaking, you knew you were going to have to pull the head to fix all that was wrong (and do some preventative repairs while you were in there). You are obviously a very good technician and teacher, thanks for making the videos!!! It's an Excellent series, I've shared them with my son and brother that own PT's.
I WAS VERY IMPRRESED AND IM LeaRNING Lot fromt tgat video good jpb keep up the good work
Really nice to watch a video by someone who knows their stuff vs some of these videos out there where they just want to show off all their snap on tools. I admire the detail you put in you work.
Question: Are you mostly self taught and always just loved working on cars or did you go through a lot of training to get where you are ? Again, great videos David !
Thanks for understanding my process. I have been at the same dealer for going on 21 years now.....I like to think I am mechanically inclined and like most of you....just need the info for me to do the repair. Much like fixing the washer or dryer at the house or the a/c unit or even the plasma TV. If I have the info....I can take the task on. Its all bout finding the knowledge from somewhere. I have worked on cars one way or another since I was 16 so its pretty much my life I guess.....I wouldnt say that I love it, its more of a saving money and fixing it myself thing. I never run outside happy to work on anything lol. I like the money and I can do this job so it works well together lol. Thanks for reaching out and make sure to subscribe Ron if you havent already
Thank you David. Good job. I appreciate your videos. Have a blessed and safe week.
Many thanks Billy! You do the same!
Thank you EXCELLENT explana tion!!
Thanks a lot Fred!
Great information and descriptive learning Dave. Valve to valve contact was a prominent issue in early multi valve overhead cam diesel engines with primate electronic injection, where the early belts or chains failed, especially in Australia where extreme heat, multi trailer combos are prominent. In all engines failures I've diagnosed with this description, the valves had not touched the pistons, due to the volumetic concaved pistons (increased volumetric area), but had edge contact with the opposing bank, resulting in major valve head degregation, from chips to complete severance. Other diagnosis of terminal failure include exhaust valve failure due to Jake Brake failing to release after disengagement, Hobbs switched fans causing belts/chains to jump a notch when engaging due to failure of soft start mechanism affecting cam timing, early ECU failures, most notably on Euro trucks with primitive VVT, losing sensor activity, suddenly engaging limp home without warning, and regarding the timing without confirmation of either cam / valve positioning. Add the failure of belts due to atmosphere and mechanical exposure, and overstressed timing chains, and you have very expensive repairs as the engines were usually destroyed by shrapnel from valves and / or disintegrating turbo turbines. Oh....one funny issue seemingly encountered on industrial Detroit diesels was the engines would fall out of timing without warning for no obvious reason but never damaged valves. When the heads were removed exposing the combustion chamber, the valves, usually inlet, had caught the edge of the exhaust valve, rendering retraction impossible. 👍👍
Good stuff! Always appreciate your help, which is always spot on!
Thanks for joining in on the premier! Much appreciated
My friend had PT cruiser i warned him about changing the timing belt but it broke and the exhaust valves were badly damaged the pistons hit the exhaust valves
Thanks Patrick.....appreciate that comment. Timing belts are important to stay on top of as far as changing them when needed.
Great explanation Dave. Like you, Chrysler made it more difficult to understand and we all learned something about valve to valve vs valve to piston clearance.
Thanks Wyatt! I learn something everyday so I learn with all of you watching.
always told to never" assume" because it will make an ( "ass" out of "U" and "me"). How can we now take the manufactures bulletins as always being true after what you proved. Love your presentation and your method of analyzing each step. Please keep the videos coming and thanks for your time.
Thanks Brian! Your right about assuming lol. I only believe what I see for the most part. Its rare that I dont agree with the service info. You keep watching and I will keep making videos when ever I can.
perfect explaination sir.... YOU DA MAN!
Many thanks! I appreciate the comment and feedback. Make sure to subscribe and try to enjoy the weekend.
Very good breakdown and analysis. Definitely subscribing. You helped me out tremendously.
Food 4 thought. Instead of redo video why not just delete it to avoid investing more time into a topic that the haters will always use as ammo.
Thanks Gabe....glad to hear that you enjoyed it. Make sure to subscribe
Excellent.
Many thanks! Dont forget to subscribe if you havent already.
Excellent video David. I hope Chrysler watches these.
As long as these engines were in use you would think they would have figured it out by now.
Thanks man.....appreciate the comment and for you watching!
Great video 👀🥂👍 . Certainly looks like my 2005 pt is junk after belt broke .
Great video thanks for the help!
That was great information. Thank you so much. Keep it up sir. Very well explained.
Thanks Brett! I appreciate you watching and for taking the time to comment. Dont forget to subscribe.
Well done in your explanation,plus its the first vid ever i saw pass 300 without a dislike lol
I am surprised as well about the no thumbs downs......I know that now that I said that they will start showing up lol. Thanks for watching and Merry Christmas!
Great job Sir Motor !
Thanks Paul! Make sure to subscribe.
Thank you.
Your welcome Heather! Make sure to subscribe.
Another GREAT video, and great information.
Thanks John! I appreciate you checking out these videos. Make sure to subscribe if you havent already
Very interesting. Thank you for sharing, David.
awesome vid bro . you confirmed for me what i thought. cheers man. you rock.
Thanks Darryl. Make sure to subscribe.
Got em. Good shit bro. I love it. Real work
Many thanks Corey. make sure to subscribe and enjoy the weekend.
And the reason I came across your video is because I was looking to see if a 1995 Honda 1.8 engine is a "clearance" or "interference" engine. Would you happen to know? I recall there was a list of all engines listing the ones that hit and the ones that don't hit when the timing belt/chain breaks but I can't locate it :( Thank you for your time making these videos it is much appreciated 👍🏻
Morning. I havent ever worked on a Honda so I dont know for sure. I dont trust what is written as you saw in the video. I good Honda tech would know for sure but I dont know of any. Guess I am of no real help when it comes to that vehicle. Thanks for watching and for following the channel.
Awesome video brotha 👍🏻 I'm surprised in all your years of wrenching you've never heard about valve to valve contact possiblitys, we learn something new everyday right. But anyway my question is have you thought about notifying Chrysler of your findings of this situation? I wouldn't be surprised if they wanted to hire you on as an engine designer (for real) you definitely know your shit. I've been a mechanic at a Chrysler/Plymouth/Jeep dealership for 13 years so I can tell you got skills 🔧
To be honest I never even thought about the valves either. Just over looked it I suppose. I appreciate the kind words coming from a fellow tech....means alot.
This was really well done. Much obliged.
Though not an engineer, a scientist he is!
Great video! As an owner of two Chrysler vehicles with the 2.4, this is very useful info. I changed the belt on both mine at the suggested interval, and now I can see that I am glad I did. The exhaust valves did come into contact with the piston.
Did you have to replace the piston in this case? Is this discussed in a later video?
Piston was okay and I didnt seen the need. No issues with it running lol. If the belt breaks your okay....its just when someone times it up wrong or does something like in my case with the cam shaft alignment pin. Thanks for watching Kirk and for the comments.
David, Have you ever heard of a 97 3.5L break a timing belt and not have bent valves? My belt broke while idling at a stoplight ,now worried my intrepid is junk. Excellent video ! Had to subscribe to your channel!
On the older 3.5 you should be fine. We replaced them all the time back then with locked up waterpumps and broken belts. Over time the newer versions of that engine would bend valves.
Superbly done video.
That was super clear!! It is an interference engine. Congrats on the twins!! On 2016 T&C, would u take the door off when changing door lock actuator, or would u fight it with the door on? Thank u David!!
Many thanks Bill. Taking that door off is the best method. We use those fender stands that they sell at harbor freight to lay the door flat on.
Good explanation , thanks.
Your welcome and thanks for watching
wow you proved it! there are a lot of mistakes in service info that can make you go left when you should be going right
Many thanks
Thank you!! Perfect!!!
Very informative. I have 2011 equinox with 2.4 interference eng w/81K, Unaware plastic chain guide broke tried to start engine which may added to damaged valves. Having new crate engine installed ($$$). So as to understand all this, you say that pistons on non interference engines can over extend and hit valves and not visa versa? Are all DOHC engines considered interference? When looking for a new car, interference/non-interference engines never come to mind. Thanks
Funny you would say that.....we have one of those in the shop right now for that exact same issue. Seems to be common. When it comes to engines.....each is different. Some are and some arent interference. The Chrysler 3.5 use to not be.....but the later versions were. Its all about the internal make up and there is no one rule that fits them all. Thanks for asking and make sure to subscribe.
Cylinder head and engine block surface prep video would be appreciated. Thanks
Good idea.....its very possible. Thanks for the request and for watching
Thanks for this awesome vid, David. Super helpful and informative. Keep it up!
Thanks for this insight. At 11:20, it makes it an interference engine.
Is there a possibility that the factory measurements were correct, at the exception that they forgot to take in count the EXPANSION of the metal due to TEMPERATURE ? In short, is the extension different when the motor is cold and when the motor is hot ?
Anyway, GREAT GREAT VIDEO !
Many thanks ! Keep on the good work.
Another item brought up is if the head has been shaved previously. There are always a few items that you over look and dont factor in like in this case. Multiple possibilities. Thanks for watching and for the comment!
The head gasket might have been replaced before with an aftermarket item of poor quality.
Nice video.
I just bought a Honda generator (EG2800i) that I LATER found out needed a timing belt replacement after every 250 hrs. I specifically asked about the potential "interference" issue and all I got was ...... [crickets]. The service department didn't even know what I was talking about.
Regarding the PT you were working on, when you put the valves back in and cycled the valve train manually, @13:05 you mentioned the momentum of the opening exhaust valves possibly being enough to throw them into contact with the piston. . You've no doubt heard of "valve float" and that happens when the spring rate doesn't allow the lifter to keep up with the profile of the cam lobe, especially at high revolutions, and that may introduce a wear depression where the trailing ramp of the cam meets the base circle. 50 years ago, you'd see it occasionally. Today? I dunno
Have you had reason to suspect the valve spring compression? I once overhauled a Divco milk truck that had a 6-cyl flathead 225?cuin Hercules QXD engine that put out a whopping 65 horsepower. I could fully depress the brand new valve springs in my hand. Just sayin'.
Great video great advice
I have an '04 PT GT (Turbo HO). I have seen conflicting info on this topic and have wondered if it was an interference engine or not. Now I know, thinks. Great videos!!! In caution I replace the timing belt at 75k.
Great explanation of interference and non interference engines. And don't always believe what you read in a service manual.
Have seen damage from piston to valve more than once on "non-interference" engines from multiple makes. Don't forget to remove any of the sharp areas the impact points have. Don't want a hot spot to create an issue.
Thats very true! Thanks for watching and for the comment.
The service info is assuming the belt is on timing, if it jumps of course it can hit the piston, especially that engine where the piston is above the top of the block.
As a father of twins i just wanna say congrats.
Many thanks. They take your heart and your time for sure. Thanks for watching!
Serious I like your videos I love learning about cars 👍
Many thanks.....glad that I have viewers like yourself.
These videos are awesome. Is it possible that resurfacing of the head reduced the clearance enough to allow the exhaust valves to interfere with the piston?
On some vehicles it sure can.....plus you might not know that it was shaved already before and not its getting done again. I would assume a machine shop would be able to tell if it has. Thanks for the question and make sure to subscribe.
Great video!
Thanks Russel!
Well done video. Thank you.
Awesome video Man! The one thing I've never been able to find an answer for is why do car manufacturers make an interference engine the first place?
To increase compression for more power and fuel mileage.
Thank you sir.
Your welcome! Dont forget to subscribe.