Any one know?
km23honda
03-19-2004, 11:44 AM
My girlfriend yes thats right my girlfriend. Did a compression test on my car at her school. I have a 92 honda prelude Si. IT went like this.
looking at the engine right to left. 125, 185, 200, 200. After hearing this I was like something is wrong. People in her class said there was a bad valve. I don't know where to start to correct this. The car is running fine, but still that 125 worries me compared to the 200's. I do believe that those numbers are in psi. This weekend am going to re-gap the cam to the rocker. (that is all i can think to change to make it better.) But wanted to know if any one knew if there is something else i could check? Thanks
looking at the engine right to left. 125, 185, 200, 200. After hearing this I was like something is wrong. People in her class said there was a bad valve. I don't know where to start to correct this. The car is running fine, but still that 125 worries me compared to the 200's. I do believe that those numbers are in psi. This weekend am going to re-gap the cam to the rocker. (that is all i can think to change to make it better.) But wanted to know if any one knew if there is something else i could check? Thanks
FDTT
03-20-2004, 03:22 AM
Ok, well a few things could be wrong.
You could have a bad valve clearance, and that might be corrected by doing a valve adjustment.
But if it has been like this for a while then you may have a burnt valve and need a valve job.
It could also be piston rings.
The best way to diagnose the problem would be to do a leake down test. All you need to do is hook up compressed air to the spark plug socked when all the valves are closed so there is pressure in the cylinder and then listin for leaks. A leak near the bottom of the block would probably indocate a faulty piston ring. Near the top would probably be a miss adjusted or burnt valve. Also pop the rad cap when you do this and look for bubbles. If you see bubbles you need a new headgasket.
Good luck,
PS double check the compression numbers before you do anything at all on the car.
You could have a bad valve clearance, and that might be corrected by doing a valve adjustment.
But if it has been like this for a while then you may have a burnt valve and need a valve job.
It could also be piston rings.
The best way to diagnose the problem would be to do a leake down test. All you need to do is hook up compressed air to the spark plug socked when all the valves are closed so there is pressure in the cylinder and then listin for leaks. A leak near the bottom of the block would probably indocate a faulty piston ring. Near the top would probably be a miss adjusted or burnt valve. Also pop the rad cap when you do this and look for bubbles. If you see bubbles you need a new headgasket.
Good luck,
PS double check the compression numbers before you do anything at all on the car.
AcesHigh
03-22-2004, 09:22 AM
A bad headgasket. Valve seals. Bent valves. Piston rings.
You can also check your rings by pouring in a teaspoon of oil in your spark plug hole right before checking compression. If your compression goes up, then it is your piston rings.
You can also check your rings by pouring in a teaspoon of oil in your spark plug hole right before checking compression. If your compression goes up, then it is your piston rings.
jdmcivic04
03-23-2004, 04:54 PM
possibly bad valve spring?? just a guess...
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