Poor Compression.

[majik2k5]

We ran a compression test on my motor the other day, and the results didn't exactly make my day. Afterwards, we added a little under a teaspoon of oil to each cylinder. The numbers definately looked a little bit better, and cylinder 3 somewhat baffled me. However, the other night my head gasket finally went. It poured white smoke and the oil was full of water.

My question is, when the oil made the compression skyrocket, that's an indication that the rings are fried, is it not? Also, it puffs blue smoke, yet another indication. But I'm not sure if the bad head gasket would have caused all of that. My friend is getting his garage for just us to change the gasket this weekend on saturday and sunday, and possibly friday night.

I was wondering if I should buy piston rings and do at the same time of the swap. It never hurts to buy them I know, but I'm pressed for money atm, and if I don't have to change the rings I don't want to.


Regular Compression | Compression w/ Oil

Cylinder 1 - 107 | Cylinder 1 - 145
Cylinder 2 - 112 | Cylinder 2 - 160
Cylinder 3 - 125 | Cylinder 3 - 235
Cylinder 4 - 120 | Cylinder 4 - 170

 

[Lithium_31]

What altitude are you at?? It can make a huge difference. I would say that the leak down does show some ring failure, but I could be wrong. I know that hear in Albuquerque at my friends house (aproxx 5000' elevation) I had 140/141/135/139 and was told that it was fine. You will see lower compression numbers at higher altitude....

 

[majik2k5]

I'm about 1,000" above sea level, but I don't think that could make that big of a psi compression difference from cylinder to cylinder. Compression anywhere around 140 is fine no matter where you are. I've heard that elevation can make a compression difference, but I don't think it's causing me to drop nearly 40psi in certain cylinders.

 

[Lithium_31]

If you're only 1000' above sea level you should show better compression then what I have, I would definitely think about doing a full rebuild or just buying a 6bolt.....

 

[siceclipse]

did you make sure the engine was fully warmed up and you had your foot on the gas pedal when you turned the engine over?

 

[majik2k5]

The engine was warm, but my foot was not on the gas pedal when the compression test was done.

 

[talonpawa94]

The engine was warm, but my foot was not on the gas pedal when the compression test was done.

Does it change something if we do or dont push the gas pedal in the end ?? i saw no difference while doing mine . WTF

 

[BrassMonkeY]

120 isnt horrible for a older turbo engine.(i wouldnt pull an engine out over it)
as long as all the cylinders are with in 5- 7psi,(i think). your ok
because you have lower compression between 1 and 2.
my first thought would be the head gasket.

 

[Dream On]

I noticed a 5 to 10 psi increase when the gas pedal was pushed down on a friend's car.

 

[dherron]

If you would pop up say for instance Mitchell-on-Demand (Mitchell being what i have at work) or something like that and read what the cylinder compression specs you will find that it will say that you are fine til you are down to 100psi. So I would say that you are good for now just not going to have as much power as a new one. Dont be a dumbie ty I've told you this before!