-
valve marks in pistons ADVICE NEEDED PLEASE READ
by
hustonr123
on 23 Apr, 2010 19:14
-
Hey everyone I started my 89 mk2 jetta to diesel project last november. I got a used diesel engine from a jy that they said needed a head gasket. Anyways I tore it apart found a blown gasket had the head pressure tested was good so the shop skimmed a few thousands off to true it up. The motor had a three notch head gasket and thats what I replaced it with along with new bolts. From day 1 when I first heard It run the engine had a knocking noise. Over the few past months I been trying fo figure out what the noise was. Ive had the valve cover off a few times checking the hydro lifters found them all to be doing there job so that wasnt the problem. about 2k ago I changed the oil and cut the oil filter open no bearing shavings so looked good and bottom end must be still good. Ive got almost 5k miles on this engine now. But monday when I went out to go to work. It started funny only ran on 3 cyl. Now today I tore into a compression check found number 3 cyl only had 125psi rest 400 to 425. I took the head off to find every intake valve had been touching the piston and 2 & 3 exhaust valves touching also. On cyl 3 the exhaust valve is only touching the seat half way. Must be bent I will update when I get that valve out. Ive checked timing atleast five times within the last few months allways been rate on. I have all the rite tools to do the timing anyways I really dont think a few degrees off cam timing would make the valves touch. I alsp rolled the motor over tonight to make sure the flywheel mark was rite and it is. Number 1 was all the way up with the mark. The motor is a na with turbo added maybe the turbo caused this or the head was skimmed to much that is my ? for you guys. Thanks for any help and sorry for the long post. BTW this is a 1.6 hydro engine
-
#1
by
truckinwagen
on 23 Apr, 2010 19:18
-
it is possible that the lifters were bad, and pumping too far up, keeping the valves from closing all the way and mashing into the piston.
that being said, it would run like a bag of rabid weasels if the valves were hanging open, long before the valves actually contacted the pistons.
I would recommend a head rebuild and new lifters at the very least.
-Owen
-
#2
by
hustonr123
on 23 Apr, 2010 19:39
-
it ran like a top no sign of any power loss still just slight miss when warm im sure it will run even better after i figure out this problem
-
#3
by
hustonr123
on 24 Apr, 2010 10:04
-
just dropped the head off to get valves sunk into head a little to compensate for what was token off the head. I hope this will take care of my problems
-
#4
by
arb
on 24 Apr, 2010 11:38
-
it is possible that the lifters were bad, and pumping too far up, keeping the valves from closing all the way and mashing into the piston.
that being said, it would run like a bag of rabid weasels if the valves were hanging open, long before the valves actually contacted the pistons.
I would recommend a head rebuild and new lifters at the very least.
-Owen
I was first thinking it was still a timing issue, but if you used a dial indicator to check TDC of the piston with the flywheel mark, then I'm with Owen in the rebuild the head camp. Part of the rebuild would be to test each valve spring for actual compression force as well as cleaning & inspection of the lifters, at least that's how I was taught.
-
#5
by
hustonr123
on 24 Apr, 2010 11:55
-
the guy said he would reset the lifters by puttin them in a vice then when i started it they would set there self in 1 piston a intake valve put a mark it in the rest of pistons i can see how close they are in the carbon. I trust the guy doin the work he said sinking the valves is only way to fix the head.
-
#6
by
sdwarf36
on 24 Apr, 2010 18:13
-
The spec for valve recession is .040 to .060.
-
#7
by
hustonr123
on 24 Apr, 2010 20:18
-
i didn't check mine but doubt it was even close to that i also like to add that my motor has seen 1200+ egt post turbo the first thing i looked for when took the head off was something melted every thing was same as before. there little engines are bullet proof I have been thinkin about adding squirters or doin ceramic coating in the future. I feel doin ether of those now is unnecessary and not as beneficial as what I wants thought.
-
#8
by
hustonr123
on 27 Apr, 2010 18:06
-
somebody help I just put my car all the way back together ran good for about 20min. The same noise came back and back down to running on 3cyl. Its also number 3 cyl again. I made sure b4 I left the place that did the work that he showed me the valve recese. It was between 50 and 55 thousands on every valve. So what can the problem be now. could the lifters be bad to much oil pressure going to them. could the oil pump be junk.
I just put 70 bucks worth of gaskets and bolts I dont want to waste them. this POS is heading to the scrapper.
-
#9
by
vanbcguy
on 27 Apr, 2010 22:21
-
I know this is a long shot, but maybe you have a bad injector or delivery valve and the valve imprints were unrelated?
-
#10
by
arb
on 28 Apr, 2010 09:07
-
I just put 70 bucks worth of gaskets and bolts I dont want to waste them. this POS is heading to the scrapper.
Don't do that !! Contact me before you do that. I could use a core to rebuild as a spare for my Caravan.
-
#11
by
hustonr123
on 28 Apr, 2010 10:08
-
can somebody tell me what they think the problem is be smartasses Point me in the rite direction
-
#12
by
truckinwagen
on 28 Apr, 2010 10:12
-
did you replace the lifters?
if they are failing, and pumping up too far with oil, it could cause the valve issue.
-
#13
by
Vincent Waldon
on 28 Apr, 2010 10:13
-
Pretty hard to diagnose noises over the internet... what are your compression readings now?
-
#14
by
hustonr123
on 28 Apr, 2010 10:24
-
plan to check compression tonight will post back