3a4s

Just finished replacing my right side head in a '96 2.8 12v. Also changed the cam and lifters. All three were from a 55k car, and seller said they were from right side, so I have to take his word, since he is very reliable. BUT... after I took all precautions, used the correct cam sprocket holding tool, and crank holding tool, I have no compression on #1 cyl. When the two cam plates are correctly lined up the #1 lifters are up (exh) and down (int). Is that right for TDC? The marks all line up on damper and hand painted marks on belt and covers. Chilton says TDC is on #1 for the SOHC engine. I would have guessed that both valves would be closed at TDC, so I should see both lifters up, correct? I've rotated the engine by hand several revolutions, and there are no interference issues. The previous mechanic supposedly made a mess of the left side head and perhaps the timing as well, before I bought the car, so maybe he installed the other cam backwards, but who knows. Can anyone help solve the zero compression mystery?

Audi0s

You might be 180 degrees out. I think the larger pin on the cam locking bar is on the inside.

jseklund

This could be a lot of things and I just went through a similar issue with my mom's A6.

As stated, you may be 180 degrees out, but if you had the locking bark on and the crank pin in, I don't see how this could be.

Another thing you should try, which took me a while to find - set the engine to TDC (just for a good reference point). Turn the cams 90 degrees and let them sit for 30 minutes, repeat, repeat. This will recompress the lifters so that they function properly.

Did you count the chainlinks between the cams? they should be 16 links on each side. If those are off, you could have the exhaust cams timed right and the intake cam off - or everything off.

5v/cyl

He has the 12V SOHC engine.

jseklund

Doh, my bad. Got over zealous in my desire to help out...sorry.

4Driver4

TDC isn't true TDC. If you are using the bar and pin, the timing is right.

jschick

did you by chance set the cam timing before you bolted down the head? or did you just bolt down the head then turn the cam so the bar fits? it is possible to bend valves when torqueing the head if you did not set the cam properly. Generally i would spin the cam it will line up, then put it on the block, check again then torque it down with the cam bar in place

3a4s

I actually bench mounted the cam in a neutral position before installing the head. Then used the bar to rotate the cam down with the #3 at TDC. I felt certain the valves would be fine because the other two cylinders were well down in the bore, and #3 was up, which meant that the valves were closed. Anyway, I squirted oil down all plug holes, disconnected fuel, then cranked it and whatayaknow, I got good compression on all cylinders! Thanks for the timely advice. Now all we have to do is replace everything and put some good gas in the tank and fill up the radiator with blue-green G-12. Can't wait. It's been almost one year since I bought the car and have not heard it run yet.