There’s been a company here in oz selling stainless valves for holdens for the last few years, being a fairly reputable company with all the claims of being the best! a few engines I’ve worked on lately ended up with these “performance ss valves” they have more faults than features the main one being a very rough cut stem,rough enough to file out a set of guides in two weeks in my l36 v6 turbo and made it a v5, so smart me buy’s another set but polished the stem and honed the guides and they lasted a month before guide wear became excessive,im using zz valves now for the last year and no signs of wear
My girl freind ought a car ran amazing till the timing belt broke, I checked it over and over did leak down and seemed to pass, how ever it did have a bent valve (was not leaking how ever) I know because I did a leak down test on it to ensure no bent valves, then it had over heating issues shortl time later discoverd the head gasket was leaking, so the head had to come off any ways then had the machine Shop check it over and came tro have a valve that was bent I assume from when the belt broke the guy was even in shock of how it even sealed period, but so was I lol.
I learned this the hard way. I had a guy that I tried to team up with that he knew the all end to be all about his engine. As it turned out, I would help him make it work the third time. He not only changed the cam timing , he g
@@WeingartnerRacing Brother, I worked in performance machining and engine building at Hoosier Parts in Seymour Indiana from '90 to '92. We built stuff for all kinds of guys and I balanced reciprocating assemblies for everything from Rodek and Hawk and Keith Black blocks as well as all manner of factory iron blocks and World Products stuff. I CANNOT say AMEN enough times to this video subject. Not only firstly,,, that every guy who CALLS himself an engine builder, isn't necessarily, an engine builder... [And everyone makes mistakes now and then] BUT,,,, ONCE a valve kisses something,,, if I SEE it had contact,,,, it's back out of there, and if it turns true in the Sioux.... I still tend to want to replace that piece. It's just TOO easy at that point. But once you're looking at an original numbers matching engine in a totally rotisserie restored 71 Hemi Cuda convertible, or a 69 Shelby GT500 Mustang or a 69 COPO Camaro,,, and something blows a hole in that original cast iron,,,,,, man,,, the kind of guys who could afford all that in the first place,,,, WILL be able to afford a knarly attorney too. Never EVER re-run parts that have crashed. Not unless it's in YOUR OWN BOMBER. I have a couple of my own builds that have some historic parts in them thanks to hangin" around the pits at the US Nationals since 1980 with a buddy who really got around and snagged parts from people like Shirley Muldowney and Big Daddy Don Garlits and John Force in his early days. We were such nitro rats that we bought and cobbed stuff out of the dumpsters at the back of the track if the teams wouldn't sell it for fear of liability. My pictures with those teams are some of my most cherished belongings these days. Anyway,,, really great advice you laid down here. If you can see contact happened,,, there's virtually no way there wasn't damage.
THis is gospel true! Thanks for the video Eric! If I have doubts , (I don’t have a valve grinder) but I just chuck the valve in a drill- you can usually see if they are bent right away.
Using a lathe (thankfully I own one) works well also. But you are correct, this method will tell you really quick if you have a bent valve. Or if they all are wobbling, your drill needs replacing. LoL.
I learned this recently the first time I built a BBC engine. It all started when I messed up measurements fly cutting the pistons. It felt fine rotating it by hand but the first time it ran it tapped. I pulled it apart and saw what happened. After I fixed the piston I checked the chamber held fluid on the bench and compression was good. I started the motor and it kicked back. That's when I realized my second mistake. I took the engine back apart, replaced the valve a couple months ago, and now the engine has maybe 1000 miles on it. I barely have a clue what I'm doing but at least I am paying attention.
That makes the difference in being a tech and being an assembler. Everyone has missed before, if they're actually working. But when you have the knowledge and experience, you have also developed the patience to see it through on a complete disassembly and inspection. You knew there was a problem, and you stuck with it to find everything. When working on engines, especially those close tolerance performance built ones, this is what it takes to make them live.
One word CLAY... I clay every engine i build. Before and after flycutting my pistons. I check all clearances and degree the cam in too. Just because the machine shop said it was good dont mean it is. It gives me peace of mind knowing i checked it.
I think stories are great. They add time, but it's not wasted. Besides being entertaining, the story gives your mind something to anchor the lesson to, and that really improves retention.
A very WISE old Machinest and Old School Drag Racer from the late 60' threw the 80's I knew. Told me that if you don't have time to listen to the whole story when someone is trying to teach you something. And is sharing proven knowledge with you. Then you need to slow down a little, Because if you don't. You better have deep pockets, Because you're going to need them. Because when stuff starts to prematurely break due to your lack of knowledge. That what he called "Paying the STUPID tax" And some guys will just never learn how to stop having to make those payments.... As the saying goes, "You can't fix stupid" However, I added a second line to that. "But we will laugh at you, And grade it on a scale of 1-10"
Never fails!! Im just glad you were able to convince him to tear it down. The people I know don't list to my brother and I until their stuff grenades!!
the mugs from the regular show and the characters name is muscle man...but that's not why I'm here...years ago I was doing a job on a Lister generator (English made diesel engine) in out back of South Australia and after I finished that job the farmer asked me if I knew anything about Chrysler straight six engines, yeah a bit I replied, he told me he had just finished rebuilding it and went to go start it up and the engine went bang and near exploded! So we start walking to the shed and he was telling me how he read the workshop manual a million times before he attempted to build it and he had a laugh when he read in the manual that the piston valve reliefs had to face the passenger side and how he thought that was an odd way of explaining how to assemble the engine... to which I replied YOU DO REALISE THAT AMERICANS DRIVE ON THE OTHER SIDE OF THE ROAD RIGHT? ... needless to say we never made it to the shed and as we turned around to walk back to the homestead I said that's why you should stick to farming and I'll stick to being a mechanic!
Thank You Sir!! Another easy at-home check...... Take the head off. Remove springs. Shine light in chamber while looking into port rotating valve on the seat. You can see a bent valve from a mile away.I use this as a quick go/no go for reusing unknown valves. If they are tweaked, throw them away. As our host said, they will break
My 35 year old son said it's the " Regular Show"! I was thinking the valve would ruin the seat and guide but when you said the valve broke it became one of those "oh yeah" moments. Great work Eric!
I've seen messed up valves push in the seats on aluminum heads, and other bs liek valve guides and seals getting mangled. Happens a lot after timing belt breaks when you just toss on a new belt.
bet if ran at low rpm long enough it could destroy the guides before the valve actually breaks too. so it could potentially be a very expensive mistake on a new set of heads.
Outstanding video ! It makes me smile to know there are young minds,former students, out there who will go thru life with a bit of Eric in them.They'll remember it forever.THANK YOU !
The regular show. It funny because he always bags on his own mom instead of his buddies. He doesn't really get how you're mom jokes work but he thinks there hurlarous. Great video thx. 231 area Michigan
He's lucky he did not break the valve off and ruin the head. And send it through the piston. Destroy the engine. You were correct with your advice Eric. Thanks for sharing. Take care, Ed.
I bet if we could get AFR to do a video about the heads they warranty. Due to the "Wing Nuts" that put the engine together incorrectly. It would SHOCK you. But because they have taken the "NO Questions asked" Approach on there warranty (Within reason) They eat a lot of problems that where not there fault. All just to keep there customers happy and to retain such a high standard of quality and service in the industry.
It would have Ben Less apparent if the engine had ever ran right from beginning I built A lot of solid roller shaft Toyota 22RE motors It's very noticeable when you have Valve cupping or sucking up into the seat or having interference Especially on a 4 cylinder because you will keep having to adjust Valves I've had that 1 break off in the cylinder And ruin the whole build It's a lot harder to notice on A rowdy Cam V8 If you have enough experience you can spot In the way it Runs But I am a 25 years plus Mechanic And had similar issues on new buildsLove these videos for dressing issues like this
This Is the most Incredible cylinder head video I've ever seen !! No Normal engine diag testing procedures (cyl compression test or head port vacuum test pull) would indicate Anything bad or damaged !! I don't understand the test results but can Sure explain some freak valve head break offs reports I've heard about.....Thx for showing this..
@@WeingartnerRacing I vote for more story time. Why??? Because I personally can relate better to it. And often if you're listening to the whole story, You'll gain other knowledge other than just the topic .
Very thorough video Eric... picked up a lot from this video... very important for first time engine builders ... even experienced builders... easy to overlooked.. keep up the good work
Hey Eric, Tim here........yea, i saw the comment about an assembler and a tech.......i assemble engines, with SUPER anal detail......i'm NOT puttin my name on any piece of crap!!....this vid was EXTREMLY important, and VITAL to the life of a motor assembled by a person who doesn't know what to look for, and then blames somebody else, where it was their own lack of knowledge, and quick assembly that created their motors demise......when i blew up my Poncho 462 yrs ago.....i knew valves hit pistons.....i didnt even have them checked, i bought ALL new valves, cuz i was AWARE of this exact issue......i just made sure the guides were good.....put all new valves in it....made sure back cuts were exactly as Kauffman did them, and i'm back to same power, with reliability......PRICELESS knowledge for the backyard dude in this vid......people like me and you know, but BOY, GREAT vid for them (the non knowledge peeps)....again, u shuda been PAID damnit!!........Sickens me......it PROVES how valuable ur vids are....LOVE the chanel so much, cuz i learn all the time.....and i've been doin it for about 40 yrs......the moment you think u just slap it together, is the moment ur motor most likely will see catastrophic failure...and DONT be Dr. Ego......you can ALWAYS learn somethin.....LOVED it......PEACE my brother!!
Reminds me of biulding motorcycle engines, I have guys always asking those question or they will wanna run a HUGE ass cam that requires bored over bucket lifters and lowerd valve guides and they wanna run like 14:1 compression on stock bore cylinder and I'm like "That's not gonna work there is gonna be so many things to change or even if it does work you've got to much cam and to high of compression" and then they end up buying it anyways and they try to install it then they have a ton of issues or break stuff. Oh some parts will work together they find out and they end up with an engine that runs OK but don't make the power that they wanted or hoped for. However I don't hate on them or anything like that I know a lot of people like to experiment and learn.. It's how I learned what I know (not that I know everything)....I meanI put a Turbo on a 110cc Chinese dirtbike haha. BUT point is if someone else is knowledgable and you know it take their advice or their expertise to learn from.
Like the muscle man coffee mug from the regular show. Used to watch that with the kiddo. What a strange cartoon, lol. Swear the writers were on acid, also the same as Adventure Time, lol.
great job explaining this type of errors, if we don't learn from our past mistakes or others like you sharing this video, then go right ahead and make this mistake. just learn from the pros sharing this priceless info. for freeeeeeee. You the Maaaaaannnn.
Thanks Eric, New Sub here. Fan of Old Man Garage, you could say he sent me. I have to laugh, Because "Tony" is the same guys we see in the firearms industry thats try to build a HIGH END AR-15 on a budget. And stopped giving advice to have them try and fix it themselves, My conversation goes like this " IDK man, But my Gun Smith will figure it out for sure. And is blowing it up and taking the chance of getting hurt. Or destroying all your expensive parts worth taking a chance??" I absolutely 💯 agree with you on this video. Bent or damaged valve (s) are one of the top 5 things that leads to catastrophic engine failure. Yet individually, They are one of the CHEAPEST things to just pull and replace with a know good part on the engine (thats not a consumable). I guess I'm lucky to have a lathe at my disposal to at least be able to check valves to see it there damaged/bent. I know you're going to probably cringe at this next statement. But even chucking a valve up in a drill will give you a good idea it the valve is bent or not. And if you do this as a home builder (As we are seeing a lot of guys doing these days with the LS engine swaps. Using high milage recycled or salvage engines) and find one damaged using this method. Its just as easy to start over. Check your guides and inspect the seat, And go with a new valve and use the proper method (s) to install it correctly.
Major issue with late model stuff. Unless you pull it apart and check you won't know till it's too late. With 12,000 valves per cylinder it is a pain in the arse.
Dang I actually been hearing stories about broken valves and wow just because the piston was on backwards it broke the valve so cool story for all of us to learn
Another good video. I have also had bent valves destroy seats and/or knock the seats out of the head. I would like to see your vacuum tester for valve leakage as I have one but always looking to improve my tools.
My uncle has a vw jetta we take it to mantainment service to replace timing belt and other things like water pump etc... original replacements but 6 months before the timing belt broke, it don't seems to me to be changed at all so thank you for the advice I'm almost sure now we have to replace some valves it took good the compression test but it doesn't sound good at all
Good advice Eric. Also, a gearhead at home could easily feel and see this issue while hand lapping the valves, and the valve lapping compound and tool are inexpensive. This simple procedure can catch a lot of issues by feeling and looking to see if you have a completely lapped surface all the way around both the valve and the seat without the pressure of the valve spring. Then they would know if it needs new valves and/or a trip to the machine shop.
I was having what i thought was ignition break up between 52-5800 but would pull clean before 5200 and after 5800, valve float crossed my mind several times but the tach would bounce so that kept me on the electrical/misfire route for months. Changed all ignition, distributor, wires, plugs, everything no change so finally pulled the valve springs and found 3 that were between 30-60lb light on seat and 1 that was 80lb soft at lift. Scoped the pistons and found 2 with contact marks so pulled the heads spun the valves in the ole drill press and found 6 intakes/2 exhaust valves bent, checked the pistons again and sho nuff they all had tapped. New set of valves and springs later ran like a champ, now i know to just change the springs every winter to save me from dealing with that shit mid season
Done a similar thing myself. I built a Formula Ford 1600 engine up with pistons the wrong way round. It's a flat head with chambers in the pistons with cut outs for the valve heads. You might think you would feel them hit at TDC, but I turned it by hand with the plugs out and there was nothing at TDC to suggest a problem. It ran 4 test days before an inlet valve broke and broke the piston and the head. Very expensive. I only mention this to highlight that you may think you'd feel it turning the engine by hand, but you don't always...
A friend back in the day bent 8 of 16 valves on a 4 cylinder neon r/t with a broken timing belt. Slapped a belt on it and ran it. The problem "took care of itself." Drove it that way for 2 years. However I think metallurgy (lower quality than today and lower hp) played a part.
I had that exact thing happen only it was when a timing belt had broken. It was a Honda. Mechanical valves. So initial valve adjustment was good. .010 intake. .012 exhaust. Put it all back to whether ran great. But sometimes it would misfire at idle. Only some times. Long story short as the valve rotates the slightly bent stem would cause a zero lash situation therefore holding the valve open causing a misfire only at idle sometimes. Bottom line if a timing belt breaks you better look really close for the witness marks on the piston. It was there. Very faint but it was there. Couldn’t see anything on the valve Lesson learned
@@nicholash8021 Ya unfortunately I don't think Eric messes with the Mod Motor heads. Not sure where you are at but I am friends with Manny at HPP Racing. Give them a call and ask them who they get their heads worked from. No Eric I would never steal work from you but HPP only deals with Mod/Coyote builds and run Steve Morris engines in their Street Outlaws cars
@@nova467spanker I'm in MA. I just took these heads off my motor and they look extremely well done from the factory with very little room for porting. The heads are very shallow and there is only one obvious nub I'd grind down between the valves. I think the intake and exhaust port matching is about all that makes sense to me. I just can't understand why the stock motor puts out only 305hp with a head like this. Are the cams that bad?
Yep if it does anything it is bent ,and the si valves, we had them in a mild race engine and they popped off,had them tested spider crackes, and temperament .
I have had new heads from manufactures that where seats were cut so far out of line that the valve would stick slightly to the seat.I know this is crude if you drop Valve that you know is not bent,no lube it should bounce slighty.
It happens fairly often. We have found it to be pretty common on brand new late model engines. We have had it happen a lot on new ecoboost engines. The smaller the stem like these new motors with 5mm stems it can bend a valve and the spring will pull it right back into place. It will pass every test but if you pull them out of the head and spin them in a grinder they will be bent.
See this all the time with Hondas. Small stem valves don’t need much pressure to straighten up enough to check good on a compression or vacuum test. Had two guys make the same mistake in the last month.
Im glad you mentioned Morel lifters. I've got a set of hyd roller morel lifters and they are NOISY. I hate them. If it wasnt for the fact that I cant remove them without taking my heads off (small block mopar), I'd have thrown them in the garbage and bought something else. I HATE them.
Yep, it's a lot more common than people think, it's a little surprising no one else has done a quick video on it? Choke or throttle plate screw falling into intake is kinda common I've only seen it a few times on motorcycle engines as majority of motorcycle mechanics know pistons only fit one way (plus they usually have an 'arrow' pointing towards exhaust side - 'hemi style heads) Worst one I saw was kid who was doing his own engine builds, fitted bunch of tuning parts that should have voided warranty but on the third major blow up his mother called shop and we picked up bike before he had a chance to fit stock cam, exhaust and carb back on it. Engine was completely trashed, even crank was damaged when piston crown gave way and valve head dropped through!
I’ve proven the solvent test to many as inconclusive at least by itself,I’ll use brake clean to fill the ports or chamber but hit the seat with a jet of air any bubbles and test failed, those bent valves though would have dropped for sure especially stainless
I had hard time beieving that valve chucked in the grinder held fluid & vacuum, but perhaps it was minor enough that valve spring pressure made it flex back on the seat. Tulip would work harden in short order and snap off. Absent other tools, re-lapping valves to verify seat width/location is uniform all around would be a good starting point in evaluating things.
Had a mibishia double over head cam 4valve belt broke pulled head off found 6 of 8 exhaust valves heads broke off and and pistons had cracks on top replace the whole engine belt broke at high revs
Damn. Thank you very much for this video. I've been there and if I just didn't have a bad feeling I would have blown up the engine I was working on. I got lucky
