nominal compression for the 3800 SII is 140 LBS per cyl. Yea you got issues, im sorry to say


Massey

 

The engine has 187k on it. i took it to a shop down the road from me. You guys will love what he had to say. I looked at him like he was crazy. He said "It is just a low compression issue, it won't hurt the motor any. You probably have another 100k on that engine. Your power want be as strong but can still drive it just fine." I was like yea I know it will drive but that can't be good for the motor. I may just see about putting a new motor in it. Anybody got a v6 they wanna part with? LOL

 

Low compression isn't necessarily bad for the motor. The engine has low compression because it's already bad. The low compression is the effect, not the cause of the engine problem. So no, the guy at the shop wasn't totally nuts with his statement.

 

Well with your experience, where should I start. Take the heads off and have them worked, and go ahead and replace the cam while into it. The rings and pistons should be fine because they passed the wet test on the compression gauge. Or does someone want to buy the whole car. LOL

 

Something is not right? I find it hard to believe that a V6 with 4 cylinders under 80 PSI on a compression test would start at all, no less drive anywhere. A cylinder under 80 PSI will not atomize the fuel well enough to actually fire on the compression stroke. It will just backfire. I have seen V8 with 3 bad cylinders floating right around 80 that would start but never push a car. They just backfire through the carb and stalled. Any chance there is an issue with your gage?

 

I thought it may be a gauge issue also, but after checking them numerous times and still the same readings i don't think its the gauge. i wish it was. Unless the gauge is not sitting right in the spark plug hole. It is to consistent to be a bad gauge.

 

What I'm finding strange, is an engine with having 187k miles on it showing no difference at all between the dry and wet compression test. Are you using a rubber tipped push in gauge or a screw in hose one?

 

A screw in hose one.

 

When you did the wet test, are you sure you got enough oil in and all around the cylinder to coat the rings? You don't want to just give the top of the piston a squirt and call it good.

 

I would be interested in seeing what the cam lift is on the low cylinders and again the difference on the normal cylinders.

As for the choice of rebuilding what you have or getting a new engine... you will be better off in the money department grabbing an engine from a junk yard and swapping it out. Check out my thread on where to find a new 3800, there are a ton of them out there that can be bought for $500 or less with low miles. The FWD engines are the same but you will have to change out a couple parts, again what you need to do is in my thread.

Massey

P.S. here is the linky
https://camaroforums.com/forum/93-02...nt-info-57568/