no compression in cyl 2

[comsoldier20]

sooo dealership says no compression in cylinder 2. car runs and drives like crap. should i perform a leakdown test? or should i just pull off the head? there is no way to check or adjust valve rocker clearance because of the hydrolic lifters?

 

[phunny]

A leakdown test test would help pinpoint it. Why would you pull the head? I'm assuming since you had a dealer do the most simple test that can be performed you're having them make the repair?

 

[comsoldier20]

nope, I rebuilt the head due to bent valves a couple months ago. the car has never ran right after that. I didnt think that compression was an issue. thought it was electrical. I just pulled the head off and the valves look fine and so do the head gasket. pretty stumped on where to go from here. doesn't make any sense to me how cyl 2 can have no compression.

poured oil in each cylinder. there hasn't been a change in the levels. I'm guessing the piston rings are fine. anyone have an idea of what I should do next.?

 

[jakeb2011]

Leak down tester would be your best friend. get the cylinder to top dead on compression and listen out the intake, exhaust and dip stick to know if its rings or valves. Could be weird things like the spark plug didn't seal so who knows. No compression and low makes a big difference though so did you get a psi from the dealer?

 

[comsoldier20]

already have the head off, dealership rep didn't know much about engines so he had the auto tech come talk to me. auto tech told me there was no compression in cyl 2 he believes its valve related im going to do the water level test on the head today. I'll take pics

 

[comsoldier20]

Just did the water test with the cams in and no water has leaked out through the exhaust or intake valves. very weird. it appears that all of the valves are fine. guess its time to take out the feeler gauges and check to see if the head or block is warped?

also the oil level on top of my pistons hasn't changed either and its been a few days. so rings should be good

 

[rayray3k]

hmmm maybe head gasket was on wrong, bolt the head back on and see what happens

 

[hotrodssnova]

I take it you didn't do a second comp test of your own? If the rings are sealing and the head passed the water test, that leaves the head gasket or warped head or deck. Hope the stealership was right. That's a lot of work.

Edit: did you bleed the lifters when you replaced your cams? If not, you could have a partially pumped up lifter that would cause the valve to hang open. Thinking out loud here.
Edit 2:^^^^^^^^^nevermind

 

[BogusSVO]

If the tip height is too tall, even with fully bleed HLAs, it can cause the valves to crack open and drop compression.

 

[Abe'sGST]

If the dealer tech told you it had no compression on that cylinder it would be his responsability to tell you how much compression it had compared to the other 3 cylinders. His next step should have been wet comnpression test (to test the rings) and after that leak down test, by then you should know the cause of the low compression. You should have verified it really had low compression on that cylinder before pulling the head off, something tells me the "tech" had no idea what he was doing

 

[comsoldier20]

ugh, I have a spare cylinder head that has valves in it still, also I upgraded to 3rd gen lifters that were brand new and thus bled. should I just slap on the spare cylinder head? or should I torque the head back down and do a compression then leak down test? should I reuse my head gasket for this test?

also head gasket had to have been on correctly I compared it to the old beforehand.

 

[comsoldier20]

dont really mean to bump this thread but I have an update. tomorrow I am installing my spare cylinder head from craigslist. It has around 100k miles on it but all of the valves look good. I bled my 3g lifters and installed everything. I will do a compression test as soon as I get the timing belt on. if I get good numbers I will finish installing everything else and attempt to start it up.

 

[comsoldier20]

I HAVE COMPRESSION.... but my timing belt tensioner is out of spec its like 8mm instead of 4. so I have to do it all over again. oh well. will update when a start up attempt is made.

 

[comsoldier20]

PROBLEM SOLVED. THREAD RESOLVED.

car starts up like a champ!

my compression numbers from left to right (4321) are as follows. 155,175,180,175
I know the 155 isnt great but at least the engine is more balanced than it was when it was running off of only 3 cylinders.