You are awesome to watch, I have always been interested in mechanics & cars but my choices in life took me down a different career path. Now over 40 I am still trying to learn many of the basics & I am so grateful someone like you takes the time out to help others learn - you really should have over a million subscribers! Thanks heaps from Down Under.
10 years later and your videos are still teaching people. Thank you! I was bless with buying a '14 Town and Country and its rocker arms failing. Trying to fully understand how an engine works. Your video was INCREDIBLY informative! Thanks again!
Having one of my cylinder heads replaced and wanted information about it. This video was EXCELLENT...interesting the lost foam technique is used to make cylinder heads. Very clear and concise explanation. Thanks!
Pete I'm 58 and have recently become obsessed with mechanical stuff including the workings of vehicle engines. Lots of videos on the block but your video has been the absolute best explanation of how things work in the head of the block. The extra stuff on the casting was gold. Great work mate. Stew - Queensland Australia
I always wondered how the valve stem keepers actually stayed on the valve stem, (without having to open an engine up), and you answered that perfectly, I knew it had something to do with the spring tension keeping them on, but you pointed out the taper, and the taper on the cap and my mystery was solved. : )
I barely understand the teaching in our school. thanks for uploading this video I now understand. I might drop my subject and just keep on watching your videos. thanks a lot
You have by far the best youtube page. Motors are my thing and its nice to see a page that has clear hd videos and someone that actually knows what they're talking about making the videos
You are much too kind. I enjoy making videos that help people. If you are buying used parts, first look for any spot where it may have been dropped. Inspect the entire part for any visible cracks. Find out the return policy on any used part, if you can't return it, don't buy it. After buying it, have the head magnafluxed to check for cracks. It is worth the investment and you will be sure the heads you bought are solid. Good luck with your LS!
I am glad you learned something. I am working on a video for blocks. The head is the only way in and out on all engines. V8's, straight 4's, V6's....every engine needs a way to get air in and exhaust gases out. Even 2-cycle engines need a cylinder head to hold the ignition source and exhaust port.
Thank you for sharing this! I'm currently going to school for automotive technology and our professor shared this video with us. This video gave me a better picture of what is going on in the engine. It's very clear, insightful and very cool to watch. Thank you!
hello Pete! hope u having a great wknd, nice and sunny here in SoCal! B ) ok then, well even though I had previously performed this procedure, I didnt use the soap and water (good idea, thanks) so, i just performed it and confirmed. still leaking, over 50% and soap bubbles confirmed! don't know HOW machine shop performed the their test, but I'm clearly showing a massive leak at #1 cyl. didn't even bother checking the others! head is coming off, heading to shop monday with the video I took of it
Cylinder head is bolted to the top of the machine body and becomes the top part of diesel engine. Its functions are as follows: 1,Close the top of the cylinder sleeve; form a sealed cylinder working space with piston and cylinder sleeve. 2,The cylinder sleeve is pressed in the correct position so that the piston operates normally. 3,Install all kinds of diesel engine accessories. such as injection valve, intake & exhaust valve,cylinder starting valve, indicator valve, safety valves and valve rocker arm device etc. 4,Arrange intake & exhaust, cooling channel. etc. In the small high-speed machine of cylinder sleeve is also decorated with swirl chamber or precombustion chamber, so the hole and channel in the cylinder sleeve is various and make its structure more complex shapes.
Wow Thanks a lot sir, it was my first time doing my own do over of my cylinder head and my car runs like a wildfire. The video was a big help. AL the way from South Africa
Simply amazing....and the manner how it is explained it clearly gives you a picture of how this works. I recently purchased a 2002 mazda and I'm having headaches....it started with radiator running hotter than normal. The mechanic looked at it and there was trans oil in the radiator and reservior. Changed the trans coolant, flushed trans, actually cleaned the valve body. I am still having the two issues which is shifting problems especially when starting to move the pickup, sort of lack of compression and then it speeds up. The radiator also runs hotter than normal. So I just scratch my head and my farm really needs the pickup to do some work. I fear the whole thing may be damaged.
+Petes Garage Thanks and indeed the trans oil cooler was leaking. It has been changed. I still have the problem with the engine running hot so I guess it needs a diagnostics??? I use it minimally (urgency) but put on the heater on to help with cooling. Thanks again.
+Petes Garage You're right -- it was thermostat. It was removed. I still have the issue with the shifting problem and I will ask the mechanic to check pressure to see if the prob is with catalyst....thanks Pete....I really enjoy your videos that are so clear.
+Petes Garage Also realized that when I just turn on the key and start the vehicle, it revs higher than normal....if I shift to D..drive...it moves fast. Not sure if this is the MAF.....is that what you mean with "lean"?
Most new engines for 2013 will be direct injection. The fuel is injected into the combustion chamber at 4,800 psi via a high pressure fuel pump driven off a cam lobe. There are still intake valves but efficiency goes up. Injecting air into the cylinder as well is a bit away because it is more difficult to meter at different atmospheric pressures. Great thinking!
This was incredibly helpful! Reading about this from my automotive book with minimal photos is difficult to really understand it all. This video gave me even more information than I was looking for. Also, did anybody notice the little buggie on the bottom right side of the screen that got his "15 seconds" of fame starting @11:07 lol?
awesome video!!! I've been watching your vids over lunch the past few days and I have to say, you have a very clear way of describing things. A lot of people fall into the trap of taking for granted things that they know, and then fail to communicate. You make it very simple for the novice to understand because you don't leave out important details. SHAKE n' BAKE!!!
Thank you very much my friend. It is my goal to help people understand and be more confident when the have to have their car repaired or do it themselves. I try to include every little thing that is salient to the content of the video. I could just tell the "how," but the "why" is just as important. El Diablo
I'm new to your channel and I have watched a good bit of your videos. They have taught me so much of things I already thought I knew. They are very helpful and I'm sure I will continue watching them and I might be giving you a call soon.
Fuel injectors are now directly in the combustion chamber. Only air comes through the cylinder head. There is now variable displacement, variable timing, and variable cam position. Things are advancing pretty quick.
FR500's, long tube headers with X pipe and a simple CAI.... I have Catbacks only, no mufflers. Turned 280 HP into 390... natural asssssspiration. Not much money, not much work. Awesome for a V8 GT
Before you take the head of, take a dead blow mallet and hit the valve stems (fairly hard) a few times to push them open and let them slam shut. That will seat any valves that may be leaking. Then try the test again. Spray soapy water aound the valve stem to check for leaks there.
Thanks for these thoroughly explained videos Pete....excellent, simply excellent. Albert Einstein quotes: If you can't explain it simply, you don't understand it well enough". Surely you understand and can explain this complex engineering clearly. Great, great, great job! I will simply keep watching these videos. I am not a mechanic....just love watching how the engineering in machines work.
Just call me Pete...I'm not a sir, I was a Sergeant...lol. What engine is it on? There could be other issues besides the valves. Could you please give me more detail and I'll give you some suggestions.
Getting valve collets off is a right ballache sometimes when the spring has pushed the retainer onto the collets, locking them into place. If anyone is having trouble removing them, try adjusting your spring compressor so it only moves a small amount but puts more pressure onto the valve retainer. *This cracks the collets loose.* Once the collets are cracked loose, you can then adjust your spring compressor to have more movement so you can remove the collets fully. Makes the job go a whole lot easier once the collets are cracked loose, just like removing wheel hub nuts.
Any time you break open a fuel or hydraulic line there is a risk of FM entering the system. It would not hurt to flush a new filter with gas before installing it. Great idea and comment!
Very good. I obtained these samples for training purposes so I cannot be specific about the make because I do not officially represent the company. All the videos I make are my own property and I make no claims on behalf of a manufacturer. I am just trying to share the concepts and details on general operation. Gotta follow the rules :-)
A friend loaned it to me. Most Loc-Tite is pre-applied to fasteners by the supplier. Auto manfacturers would not waste the time to apply it. It would require too many controls, not to mention the variability. I can't think of anything used for anti-tampering other than special fasteners or sealed parts.
Dude, you are awesome! I'm 3D-modeling an AC Cobra 427 for animation, including the technical stuff inside. you already helped me a damn lot! thanks sincerly, Dave
The first thing I would check for is a worn cam. You could simply not be getting enough fuel or vacuum to keep the engine running at idle. Rebuilding the carb would not hurt, but it is probalby a bit more.
thnks Pete! I love my hobby! and Im always interested in hearing others experiences, trial and errors, as well as triumph over tricky issues!!! keep doing ur thang, ur videos have inspired me to start making my own. : )
Its actually an HLA.... Hydralic Lift Assist. It works just oike a lifter but is stationary. It supports the side opposite the valvle for the RFF Roller Finger Follower.
Your explanation is so clear very easy understandAnd with the way have shown with Engine Model How I not learn something from you Thank you for sharing your knowledge.
The main objective, as is with all my videos, is to show those willing to learn that engines are not that complicated and you can do any job yourself if you want to try. Of course there are variations, but the general idea is there. Glad your mystery was solved : > )
thank you for this detailed video, really good explanation sir. I think this narrows down my list of issues I been having with a cylinder head that I just got back from the machine shop that is STILL leaking "moderately" through the intake after performing a leakdown test. basically the only thing actually sealing there are the intake valves if I'm not mistaken. I'm thinking if the cam, cam guides, or lifters are damaged/won out, that it can be enough wear, to not let the valves seat properly.
You are much too kind...I just sort of wing it....my channel is all about sharing knowledge. That is a great question. I can't think of any steel used in making a car that is galvanized. Galvanizing is a zinc coating that changes the surface properties including paintability. Even if it were you could stil use lead.
very informative, i had known that the head was basically the cap to the engine, and the only way in and out as long as we are taking OHV, SOHC or DOHC, but i always wondered how they made the coolant passages, and the ports
The only time I would change them is if you take out the injectors for some reason. Other than that they should remain undisturbed. Spraying some WD40 on them occasionally to keep them soft would not hurt.
You, my friend, are the entire reason I make videos; to help people learn and understand. Thank you for watching!
You are awesome to watch, I have always been interested in mechanics & cars but my choices in life took me down a different career path. Now over 40 I am still trying to learn many of the basics & I am so grateful someone like you takes the time out to help others learn - you really should have over a million subscribers! Thanks heaps from Down Under.
Thank you very much my friend
As a veteran....thank you for being a rider for the Sons of Liberty. You are doing a wonderful and very respectful thing....I admire you very much!
10 years later and your videos are still teaching people. Thank you! I was bless with buying a '14 Town and Country and its rocker arms failing. Trying to fully understand how an engine works. Your video was INCREDIBLY informative! Thanks again!
Thank you my friend
Having one of my cylinder heads replaced and wanted information about it. This video was EXCELLENT...interesting the lost foam technique is used to make cylinder heads. Very clear and concise explanation. Thanks!
An educated consumer never gets taken advantage of.
Thank you for watching. A 20 minute video takes a few hours to make, but I enjoy sharing what I know.
Pete I'm 58 and have recently become obsessed with mechanical stuff including the workings of vehicle engines. Lots of videos on the block but your video has been the absolute best explanation of how things work in the head of the block. The extra stuff on the casting was gold. Great work mate. Stew - Queensland Australia
Thanks Stew, I appreciate that
Good, detailed explanation...
The visuals help out immensely... the foam head and the cutaway were impressive... thanks...
Thanks my friend, gotta have good props
👍props on the props... 😆😆😆
I always wondered how the valve stem keepers actually stayed on the valve stem, (without having to open an engine up), and you answered that perfectly, I knew it had something to do with the spring tension keeping them on, but you pointed out the taper, and the taper on the cap and my mystery was solved. : )
Thank you for a great description of the cylinder head and valve components.
Glad you liked it
I barely understand the teaching in our school. thanks for uploading this video I now understand. I might drop my subject and just keep on watching your videos. thanks a lot
I'm happy they help you
You have by far the best youtube page. Motors are my thing and its nice to see a page that has clear hd videos and someone that actually knows what they're talking about making the videos
You are much too kind. I enjoy making videos that help people. If you are buying used parts, first look for any spot where it may have been dropped. Inspect the entire part for any visible cracks. Find out the return policy on any used part, if you can't return it, don't buy it. After buying it, have the head magnafluxed to check for cracks. It is worth the investment and you will be sure the heads you bought are solid. Good luck with your LS!
I am glad you learned something. I am working on a video for blocks. The head is the only way in and out on all engines. V8's, straight 4's, V6's....every engine needs a way to get air in and exhaust gases out. Even 2-cycle engines need a cylinder head to hold the ignition source and exhaust port.
Nice explanation of the workings of a cylinder head. I have just had mine ported and now I know why!
+Karl Donovan It makes a huge difference. Thank you my friend
Thank you for sharing this! I'm currently going to school for automotive technology and our professor shared this video with us. This video gave me a better picture of what is going on in the engine. It's very clear, insightful and very cool to watch. Thank you!
Glad it was helpful! What school?
Thank you....its a bit choppy. I had over 20 minutes of video and had to cut it down to 15. I should make another one with the extra footage.
You made my day...thank you. I am happy to help anyone willing to learn....thank you my friend!
ahh finally i understand the difference between the valve seal and valve spring retainer! ! ! Thanks a lot :D
Thanks for the lesson! I’ve worked in machining (head) for 4 years and never knew the full anatomy of it.
Happy to help!
What an incredible lesson, and all for free! Thanks so much!!
You're very welcome!
It is very helpful for me, i just started working in a cylinder head factory，thank you very much!
You are welcome!
hello Pete! hope u having a great wknd, nice and sunny here in SoCal! B ) ok then, well even though I had previously performed this procedure, I didnt use the soap and water (good idea, thanks) so, i just performed it and confirmed. still leaking, over 50% and soap bubbles confirmed! don't know HOW machine shop performed the their test, but I'm clearly showing a massive leak at #1 cyl. didn't even bother checking the others! head is coming off, heading to shop monday with the video I took of it
Cylinder head is bolted to the top of the machine body and becomes the top part of diesel engine. Its functions are as follows: 1,Close the top of the cylinder sleeve; form a sealed cylinder working space with piston and cylinder sleeve. 2,The cylinder sleeve is pressed in the correct position so that the piston operates normally. 3,Install all kinds of diesel engine accessories. such as injection valve, intake & exhaust valve,cylinder starting valve, indicator valve, safety valves and valve rocker arm device etc. 4,Arrange intake & exhaust, cooling channel. etc. In the small high-speed machine of cylinder sleeve is also decorated with swirl chamber or precombustion chamber, so the hole and channel in the cylinder sleeve is various and make its structure more complex shapes.
Just wanted to tell you that you have great videos and it looks like you have a great time in your garage! Keep the videos coming!
Best explanation of how a Cylinder head works ever! This is pretty amazing. Gotta share it as much as i can.
+Kaktus Jack Thank you very much
Wow Thanks a lot sir, it was my first time doing my own do over of my cylinder head and my car runs like a wildfire. The video was a big help.
AL the way from South Africa
That's awesome! Thanks for watching
I'm glad you like it. It really helps diagnosing problems if you understand how they work.
This is by far the best explanation I have ever seen. Thank you sooo much
Thank you very much
That is really cool for you to say and I really appreciate it. Thank you for watching...it is a blast just to hang out in the garage.
Wonderful explanation on cylinder heads
Thank you for watching and good luck in school!
This is so awesome. Great tutorial. I am teaching my son engine basics and this is so simple and thorough to understand. Please make more videos.
Thank you my friend. I have over 100 videos and I make them as fast as I can.
This was like the best seat at engineering class free of charge. Gracias.
+dss2mtm De nada mi amigo
Simply amazing....and the manner how it is explained it clearly gives you a picture of how this works. I recently purchased a 2002 mazda and I'm having headaches....it started with radiator running hotter than normal. The mechanic looked at it and there was trans oil in the radiator and reservior. Changed the trans coolant, flushed trans, actually cleaned the valve body. I am still having the two issues which is shifting problems especially when starting to move the pickup, sort of lack of compression and then it speeds up. The radiator also runs hotter than normal. So I just scratch my head and my farm really needs the pickup to do some work. I fear the whole thing may be damaged.
+Carlos Avila Sounds like to transmission oil cooler is either leaking of blocked. Change it
+Petes Garage Thanks and indeed the trans oil cooler was leaking. It has been changed. I still have the problem with the engine running hot so I guess it needs a diagnostics??? I use it minimally (urgency) but put on the heater on to help with cooling. Thanks again.
Might be a faulty thermostat
+Petes Garage You're right -- it was thermostat. It was removed. I still have the issue with the shifting problem and I will ask the mechanic to check pressure to see if the prob is with catalyst....thanks Pete....I really enjoy your videos that are so clear.
+Petes Garage Also realized that when I just turn on the key and start the vehicle, it revs higher than normal....if I shift to D..drive...it moves fast. Not sure if this is the MAF.....is that what you mean with "lean"?
I'm always here to help. Thank you for watching!
Most new engines for 2013 will be direct injection. The fuel is injected into the combustion chamber at 4,800 psi via a high pressure fuel pump driven off a cam lobe. There are still intake valves but efficiency goes up. Injecting air into the cylinder as well is a bit away because it is more difficult to meter at different atmospheric pressures. Great thinking!
Wow, not only are your youtube video's entertaining but very educational. Carry on the good work! :)
Thanks a lot Pete, for taking the effort of making these vids.
This was incredibly helpful! Reading about this from my automotive book with minimal photos is difficult to really understand it all. This video gave me even more information than I was looking for. Also, did anybody notice the little buggie on the bottom right side of the screen that got his "15 seconds" of fame starting @11:07 lol?
I'm glad it helped Valerie...that bug is getting pretty famous...lol
Dude you literally have like the best car RUclips channel of all time. Itd be cool if you worked on things such as transmission and suspension though.
That's a great compliment, thank you. Transmissions are really a specialty, but, I will be doing suspension vides as I work on my Cobra.
awesome video!!! I've been watching your vids over lunch the past few days and I have to say, you have a very clear way of describing things. A lot of people fall into the trap of taking for granted things that they know, and then fail to communicate. You make it very simple for the novice to understand because you don't leave out important details.
SHAKE n' BAKE!!!
Thank you very much my friend. It is my goal to help people understand and be more confident when the have to have their car repaired or do it themselves. I try to include every little thing that is salient to the content of the video. I could just tell the "how," but the "why" is just as important.
El Diablo
I'm new to your channel and I have watched a good bit of your videos. They have taught me so much of things I already thought I knew. They are very helpful and I'm sure I will continue watching them and I might be giving you a call soon.
Thanks Pete! I learned a lot. I look forward to watching more of your work
Thanks my friend
Fuel injectors are now directly in the combustion chamber. Only air comes through the cylinder head. There is now variable displacement, variable timing, and variable cam position. Things are advancing pretty quick.
All your videos and your teachings are incredible. Thank you very much for the excellent information.
Thank you for watching Aldino
Lost foam is about 15 years old I would guess. Many parts are made like this for the cost and accuracy. Pretty neat process.
Excellent explanation and cut-away, thanks.
FR500's, long tube headers with X pipe and a simple CAI.... I have Catbacks only, no mufflers. Turned 280 HP into 390... natural asssssspiration. Not much money, not much work. Awesome for a V8 GT
Before you take the head of, take a dead blow mallet and hit the valve stems (fairly hard) a few times to push them open and let them slam shut. That will seat any valves that may be leaking. Then try the test again. Spray soapy water aound the valve stem to check for leaks there.
Thanks for these thoroughly explained videos Pete....excellent, simply excellent. Albert Einstein quotes: If you can't explain it simply, you don't understand it well enough". Surely you understand and can explain this complex engineering clearly. Great, great, great job! I will simply keep watching these videos. I am not a mechanic....just love watching how the engineering in machines work.
+Carlos Avila That is so kind of you, thank you. I try to make things easy enough to understand so anyone can learn.
Just call me Pete...I'm not a sir, I was a Sergeant...lol. What engine is it on? There could be other issues besides the valves. Could you please give me more detail and I'll give you some suggestions.
Getting valve collets off is a right ballache sometimes when the spring has pushed the retainer onto the collets, locking them into place. If anyone is having trouble removing them, try adjusting your spring compressor so it only moves a small amount but puts more pressure onto the valve retainer. *This cracks the collets loose.* Once the collets are cracked loose, you can then adjust your spring compressor to have more movement so you can remove the collets fully. Makes the job go a whole lot easier once the collets are cracked loose, just like removing wheel hub nuts.
Great comment, thanks for sharing
Any time you break open a fuel or hydraulic line there is a risk of FM entering the system. It would not hurt to flush a new filter with gas before installing it. Great idea and comment!
Fantastic video, great detail, very informative and educational. Thank you
Thank you my friend
Thanks for the awesome video!
Straight to the point ! 🙏🙏🙏❤️ Much love !
Thank you my friend
Highly detailed, amazing video. Thank you!
+123yoagan Thank you my friend
Watching in 2019 & still useful! Thank you 😊
I try to make all my videos information that will last.
Thank you for your videos men they are all great. I am in college and you are a great help to me. Thank you again and keep it up 😊
Thank you and good luck in school!
Thanks Will....I try to make them have some value...not just for the hell of making them....I'm getting better
YOU HOPE I LEARNED SOMETHING!
awesome explanation!
this is the kind of stuff us newbies need!
once again! awesome explanation!
Thank you Ester
Very good. I obtained these samples for training purposes so I cannot be specific about the make because I do not officially represent the company. All the videos I make are my own property and I make no claims on behalf of a manufacturer. I am just trying to share the concepts and details on general operation. Gotta follow the rules :-)
A broken push rod will not mess up the engine unless you don't find all the pieces. Just put in new one and you should be fine. That is a lucky find.
Thanks for the upload, this is the best I have ever heard.
Invaluable. Thank you so much
Thanks Bob
A friend loaned it to me. Most Loc-Tite is pre-applied to fasteners by the supplier. Auto manfacturers would not waste the time to apply it. It would require too many controls, not to mention the variability. I can't think of anything used for anti-tampering other than special fasteners or sealed parts.
Bro your explanation is awesome 👍
Thank you so much 😀
Dude, you are awesome!
I'm 3D-modeling an AC Cobra 427 for animation, including the technical stuff inside. you already helped me a damn lot!
thanks sincerly,
Dave
Hey Dave...that's really cool. I'm glad to help
The first thing I would check for is a worn cam. You could simply not be getting enough fuel or vacuum to keep the engine running at idle. Rebuilding the carb would not hurt, but it is probalby a bit more.
thnks Pete! I love my hobby! and Im always interested in hearing others experiences, trial and errors, as well as triumph over tricky issues!!! keep doing ur thang, ur videos have inspired me to start making my own. : )
Great video sir. Extremely informative and love the details provided via the sawed off head.
Thank you Victor
That is really cool Austin....thank you very much. I try my best.
Thanks Michael
Its actually an HLA.... Hydralic Lift Assist. It works just oike a lifter but is stationary. It supports the side opposite the valvle for the RFF Roller Finger Follower.
Dude this is truly a perfect video thank you so much this solved all my questions
Thanks Zach
Your explanation is so clear very easy understandAnd with the way have shown with Engine Model How I not learn something from you Thank you for sharing your knowledge.
+Linda Lyn Thank you for watching....it is my pleasure
Thank you sir for a great detailed video!
Very welcome
The main objective, as is with all my videos, is to show those willing to learn that engines are not that complicated and you can do any job yourself if you want to try. Of course there are variations, but the general idea is there. Glad your mystery was solved : > )
thank you for this detailed video, really good explanation sir. I think this narrows down my list of issues I been having with a cylinder head that I just got back from the machine shop that is STILL leaking "moderately" through the intake after performing a leakdown test. basically the only thing actually sealing there are the intake valves if I'm not mistaken. I'm thinking if the cam, cam guides, or lifters are damaged/won out, that it can be enough wear, to not let the valves seat properly.
You gotta love combustion engines. Quite the engineering marvel.
Soon to be obsolete
Not as soon as you think
That is awesome...let me know when you do so I can check them out!
Nice vid. Informative and explained clearly. The lost foam part was very interesting too.
Thank you...I think technology is really cool
You are much too kind...I just sort of wing it....my channel is all about sharing knowledge. That is a great question. I can't think of any steel used in making a car that is galvanized. Galvanizing is a zinc coating that changes the surface properties including paintability. Even if it were you could stil use lead.
This was very informative. Thanks Pete
+Hitesh Aggarwal Thank you my friend
You are the best!
doctor: you have 15 min's left to live
pete: 0:03
That's when the length of my videos used to be limited
Thanks William...I will check it out...thanks for sharing
Not all hero’s wear capes!
Thank you my friend
I think it helps with trouble shooting......thank you.
Thank you very much! Very well explained. Waiting to see more videos like this. All the best to you!
Many thanks!
Dude. Very good explanation. Thank you
You're welcome!
Another great video. All your videos are very informative.
Holy crap! I learned so much from this video it's not even funny. Thanks :-)
I’m obsessed with this
As a I my friend
It's a pretty neat process huh? Lots fo parts are made like that. If you see a cast part that looks like foam, chances are this was how it was made.
Man, I dig your videos! Thank you so much for your instruction! This is invaluable information for a greenhorn such as myself!
Incredible explanation! Thanks man!
I really appreciated this
Thanks my friend
very informative, i had known that the head was basically the cap to the engine, and the only way in and out as long as we are taking OHV, SOHC or DOHC, but i always wondered how they made the coolant passages, and the ports
The only time I would change them is if you take out the injectors for some reason. Other than that they should remain undisturbed. Spraying some WD40 on them occasionally to keep them soft would not hurt.