Compression 176-160-180-160 is this possible?

[99vipereater]

Compression 176-160-180-160 is this possible? I have a 2g stock pistons 120k miles I just did a compression test using Schucks rental guage K-D tool #2428. The engine was cold all plugs out held WOT cranked till pressure stabilized. guage sprayed water when I de-pressurized water came from the guage not my cylinder.

 

[FLASH1970]

I would say that if you just did the test and got those results, then yes, it is possible. What is so hard to believe? The engine has 120K miles on it. Things wear out... Do a leakdown test to see where the air is escaping to. If it's leaky valves, get the head rebuilt or replace it. Still, those numbers aren't terrible. My 99 had 180-180-160-180 when I bought it with 178K on it. It now has 223K on it and still going...

 

[Calan]

Other than doing the test improperly (engine cold), those numbers don't look that bad. A little uneven, but that could be due to the way you ran the test.

http://www.dsmtuners.com/forums/articles-engine-fuel/338152-compression-leak-down-testing.html

 

[safirenside]

the engine is supposed to be warmed up before you do a compression test

 

[99vipereater]

the engine is supposed to be warmed up before you do a compression test

I'm aware couldn't run the engine to warm it up. Tearing the motor out and I wanted to get an idea of it's health

 

[Calan]

I'm so confused now.

So you are asking about compression numbers on a cold motor that is being torn down anyway?

 

[99vipereater]

I'm so confused now.

So you are asking about compression numbers on a cold motor that is being torn down anyway?

Yes, only to install cometec hg, arp studs, balance removal, timming belt, clutch and flywheel. Figured it would be easier to work on it out of the car with as much as I have planed that and the hg mating surface needs resurfaced for the mls gasket. Was trying to figure out if it was healthy enough to make it till I stroke it.

 

[99vipereater]

And the reason I asked if this was possible is because my car has high milage and a cylinder above standard compression of 178. Though I would have lost more compression than that but the cold engine could be the cause.

 

[krackit]

i think he's a little confused because if the motor is getting torn down, you will be able to visually inspect everything....doing a compression test on it is a little redundent at this point.

 

[Broken7Bolt]

I understand where the OP is coming from though, he just wants to decide if its worth his time to put the car back together for a while until he can stroke the motor out. A compression test is pretty easy so you might as well...considering hes not going real far into the motor this time

 

[speedracer18t]

you try the oil trick in the cylinder to see if the pressure raises? Those number are not that bad

 

[Calan]

i think he's a little confused because if the motor is getting torn down, you will be able to visually inspect everything....doing a compression test on it is a little redundent at this point.

This.

Was trying to figure out if it was healthy enough to make it till I stroke it.

Gotcha.

If you can't warm the motor up (and I'm guessing you've already started tearing it down anyway?), your best bet is to do a leak-down test. That is actually a more useful test anyway in most cases.

you try the oil trick in the cylinder to see if the pressure raises?

A wet compression test is a bit overrated, and isn't really all that useful.

 

[99vipereater]

I understand where the OP is coming from though, he just wants to decide if its worth his time to put the car back together for a while until he can stroke the motor out. A compression test is pretty easy so you might as well...considering hes not going real far into the motor this time

Exactly, just doing some maintinance items and didn't really want to tear it apart again if my rings or main bearings or valve seals ect. are going to fail in a few months.