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View Full Version : KA24DE Zero compression in #2 cylinder


Pro ViZIon
01-25-2012, 01:02 PM
Ok so to give you the jist of it i pulled my motor to swap heads. Replaced head with a good one and now #2 cylinder has no compression. Im running a cometic hg and arp head studs. Compression test results for the others were: #1-130psi, #2-0psi, #3-150psi, #4-150psi. The test was performed on a cold motor. What are the possible causes for this to happen?

Also when i pulled the head off there was a lot of white build-upp on the plugs, exhaust valves and on the pistons. Im not sure what that is an indication for and what the cause may have been?

Any help is greatly appreciated. I want my car back lol.

di-devol
01-25-2012, 01:44 PM
What was wrong with the other head? Are you positive it was the head?

let5l1de
01-25-2012, 02:14 PM
the jist of it.

When a regular compression test has been performed, we typically see some sort of pressure in the cylinder. Pressure as low as 20-30psi can found on engines with blown gaskets, cracked pistons or rings, bent valves (not extreme) . If 0 pressure is found in that cylinder, either the piston is not moving or valves are stuck wide open (not partially open).

~m
GR Performance

Pro ViZIon
01-25-2012, 03:48 PM
Well I replaced the head because it would leak oil out the intake side of it. I had no real idea where till I took it off and there's a little pin hole where the bolt goes for the chain tensioner.

I also thought it would read at least something. The head is torqued down to 70 lbs. The head I put on was machined and pressure tested. I don't think it would be any of the valves. How could they end up being stuck open anyway? The motor wasn't knocking so I don't think they would be stuck open.

Edit: also we ran the compression test twice on all cylinders so I know we did it correctly.

fliprayzin240sx
01-26-2012, 01:42 AM
Cam timing off?

01-26-2012, 02:44 AM
Cam timing off?

higly doubt it. it would have 0 comp on cyl 3 as well. it has to be something dealing with the valves on that cylinder

Pro ViZIon
01-27-2012, 11:08 PM
Found the problem. Both intake valves on that cylinder were bent. Getting them replaced now.

01-27-2012, 11:31 PM
higly doubt it. it would have 0 comp on cyl 3 as well. it has to be something dealing with the valves on that cylinder

told ya! ;)