Hey so I recently replaced the engine in my friend's 2001 Accord because she was burning through obscene amounts of oil and the EGR valve was getting clogged repeatedly. Anyways, the new engine has about 110,000 kms on it, I changed the timing belt, water pump, spark plugs, plug wires, clutch, rear main seal, and oil pan gasket before installing it. I believe it's an H23 engine but not 100% sure as I seem to see F23 mentioned here and there. It has VTEC. The engine was sitting at a wrecker for an unknown length of time.

The other day we got the engine started but it was running rough. So then we did a compression test. 1-4 was 100 psi, 175 psi, 180 psi, 170 psi. Also I noticed after the compression test that the oil dipstick was nearly dry (had just filled engine with about 4.5L of oil). Engine has been run for only a few minutes total. When pulling out the #1 spark plug we also noticed that the threads were coated in oil (unlike the other spark plugs).

So today I was going to try adding oil to #1 and repeating the comp. test to see if the piston rings were the problem. To get a baseline I first tested #1 without oil added. Compression had strangely gone up to 130 psi. I'm confused as to what would cause this. Anyways tested again after adding about 5ml of oil and compression increased to 135 psi. #2 was still at 175 psi.

I'm inclined to say that a valve seat or stuck valve is the issue. I'd love to hear suggestions on how to proceed or pointers as to what could be the problem.

 

Sounds like bad piston rings. Have you replaced the head gasket?

 

sounds like valves issue...if rings were worn compression should have gone up higher that 5 psi.. but if you got oil in the part of the plug that goes in the cylinder (threads) could also have a ring issue as well

.chk to make sure valve lash is not too tight ,, also tap on the valve with a plastic mallet to make it move , do not hit it too hard

still that does not explain where the oil went ,,,,no leaks ???

 

I have not replaced the head gasket. Will check valve lash next.
I can't see any oil leaks from below. I'd like to know what happened to the oil as well. I'm confused as to what could cause the increase of compression from 100 to 130 just from sitting for a day though...

Oh and when the engine was running, there was black soot coming out of the exhuast mixed with water. Probably just condensation in the exhaust pipe but just thought I'd mention it.