Compression Tester Kit

[NI_Volvo_Nut]

Originally Posted by Derry

Did the compression test last night (Gunson). I got maximum 12 bar / 180 psi consistently on all 5 Cylinders. Haynes says it should be between 13 – 15. With teaspoon of oil they all went to max 14 bar / 200 psi.

Dry or wet it takes about 8 strokes for them to reach max bar.

I suppose the good thing is there was no difference between cylinders and at the moment car runs fine with no issues, not sure if there’s anything I need to do going by the readings. Any thoughts?

^^^ This!! Leave it the hell alone!

[NI_Volvo_Nut]

Originally Posted by Derry

This one is a 10v 2.0 N/A engine CNGBiFuel.

Just quoting Haynes '...compression should build up quickly in a healthy engine, low compression on the first stroke followed by gradually increasing pressure on successive strokes indicates worn piston rings.' then it says if it improves with adding oil it indicates bore or piston wear.

Just out of interest is it a major job in fixing/replacing the bores or pistons, and would I need special tools for the job. How about the cost.

Piston rings is not a simple "replace the rings" job, the cylinders with need honed at the very least, possibly rebored, over sized pistons and crank will likely need reground with new bearing shells. And yes, you will need many specialist tools not to mention the machine shop to do the engineering work.

If its running fine, put up with the oil usage and leave it alone, it won't suddenly let you down, it will gradually get harder to start, probably not for many many thousands of miles, especially running on gas.