Valves, Leakdown & Comp test "gameplan"?

[aj88cab]

I am going to be doing a compression test, leakdown test, and valve check/adjusment soon. I am trying to get a set of baseline numbers and get a better feel for the overall condition of things. Is there a "order" or anything inparticular to look for or do that would help provide more information. What else should I look for "while I'm in there".

I was planning to do the compression (dry & wet) & leakdown (both warm of course); then the next day do the valves (cold); then do the comp & leakdown again to see if there was any change. Am I making more work for myself buy doing the comp & LD twice? What else?

The car is an '88 3.2, 118k mi, no engine mods, uses about 1qt oil in 800 miles. Sometimes blows a little smoke at start-up.

Thanks,
Andrew

[Jeff Alton]

Adjust the valves first. A valve adjustment will not change a leak down number. Why do you want to do a wet compression test? That would only be considered if the numbers from your dry one are low. The leakdown will tell you if you have worn rings, as will the wet compression test, but if you are doing the leakdown anyways, why bother with the extra step?

Jeff

[aj88cab]

Originally posted by catca
Adjust the valves first. A valve adjustment will not change a leak down number. Why do you want to do a wet compression test? That would only be considered if the numbers from your dry one are low. The leakdown will tell you if you have worn rings, as will the wet compression test, but if you are doing the leakdown anyways, why bother with the extra step?

Jeff

I guess you figured out this would be the first time I will have done a compression and/or leakdown test. That is just the type of info I need to keep me from doing those extra steps.

Thanks

[Jeff Alton]

The valve adjustment could affect the comperssion test if they are waaaaaay off. If the compression numbers are good, I am not sure I would even do a leakdown. But, it doesn't take that long. If the engine has high compression it probably is not leaking much air anywhere. If you get low numbers or a few low ones, the leakdown can help you figure out where the problem lies. I don't know how much info you already have so this may not be of use. But, when doing a leakdown, if you have air escaping out the oil tank, you have some ring issues. Out the exhaust and you have exhuast valve issues. Out the intake and you have intake valve issues, out into the atmosphere and you could have a cylinder to head leak. A stethescope is a great tool to use when doing a leakdown. A piece of hose you can hold up to your ear will also work. This way you can pinpoint excatly where the air is comming from.

Let us know how it works out.

Jeff