Here is my compression test results

I got my compression tester kit from harbor freight for $15 last weekend. not bad.

Ok here are my results.
They go front to rear. front being closest to radiator.

Driver side - 145, 145, 128

Passenger side - 130, 124, 105

This is a dry test, i didnt pour oil in the cylinders. The goal of this is to try and find why i have a bad misfire on the passenger bank. The plugs didnt show any differnt or odd colors. the plugs looked pretty good to me.

I have a inline spark tester so i may do that after i reinstall the plugs.

I did not change out the timing belt, that is another place for me to look at.
But Please advise on what i should do next??

Thanks!!!

 

The 105 doesn't look too gud Dan...........

 

Timing belt? What motor are you working on??????????
Billy's right about that 105..........

 

Leak down test time!
Hi Patrick!

 

It is a 4.1L Buick V6. Yeah the rear cylinders seem to be a tad weak. I will throw some oil in there and see if that brings it up. How much oil do i put in there?? I have to get a funnel i guess

For the longest time i have had this motor i have had a miss in the right (passenger) bank The distributer was a 79 that was swapped in because the motor originally had a computer controlled distributer. The later 70's distributer to swap in to get rid of the computer. About 5 years ago i had the coil and module go bad, it worked but the right bank of cylinders seemed to just fire at will and 1 foot long things of flame would come out of the passenger bank header and really ear peircing exhaust backfires. I repalced the coil adn such and it was fixed, but it just never ran smooth like it should. The timing always seemed to "move" on me, even if i crank down on the hold down clamp for the distributer, but i never have gone and opened it up to see if it is correct. I changed plug wires many tiems and plugs. I use regular delco plugs that are gapped correctly. The exhaust smells a bit rich but the plugs do not indicate it, but i think the miss fire is contributing to the rishness smell out of the tailpipe

 

Hi! Still wondering about that timing belt................ Yup, wet test, then leakdown..........

 

Agreed!!!!!!!

 

I forget the last time i changed it, it wasnt that long ago, maybe 3 years i am thinknig, but anything is possible. will the wet test show a head gasket leak?? I do not have oil in the coolant, quite possible it would just burst between cylinders and not at the water jacket.

 

Get it wet Dan!

 

how much oil??

 

Couple squirts..........

 

i dont have a squirt bottle, gonna use a funnel

 

Yes you did... I got it today. Thanks a Bunch.


But harbor freight is so far away (5 miles) and i have octoberfest tomorrow night, so i will be elbow deep in brats and beer (Warsteiner for Billy)... and maybe a few shots of jeger or schnapps