Compression test...won't hold psi...blown motor??
 

Hi,
I went to do a compression test on my friends 88 TII. He just got it and doesn't know much about them. I've done them before...pulled the lower spark plugs, screwed in the tester piece and attached the gauge. Its a snap-on kit. Its quality. Anyway, he craked over the motor and the gauge needle bounced but it didn't go above 15psi. I tried to got an overall compression by not holding the release button but it wouldn't build compression. The needle bounced up to about 50-60psi but then it would go back to 0. What the hell?? Why won't it hold?? I thought it was busted so I tried on my father's truck and it works fine. Has to be the motor. I got the same readign for both rotors. That what made me doubt the tester... I dont understand why the gauge wont hold compression when I dont hold the release button and air is going into it???? I started the car up to listen to it. Real hard to start. Wouldnt idle unless i gave it gas. Blows white smoke everywhere. wouldnt stop. I shut it off. Whats going on????? Please help.
Thanks
-Ryan-

pull the plugs. pull egi fuses. crank listen for loud even whooshes. if you miss a whoosh you need a rebuild

did you remove the small valve on the tester?

I must not have explained it clearly...I did all that. I've done this before.

fcturbo2- if you mean the valve you push to release pressure in the gauge, no. Its still there.

The compression tester works, I verified it on another motor. When used to test the TII motor, it wont hold compression even though the needle on the gauge bounces to 50-60psi on each "woosh"

and im not holding the release valve on the compression tester when testing each rotor for overall compression

You had the throttle floored?>

James

The motor doesnt hold compression the tester does. If the needle is bouncing to 50 or 60 psi and not holding it's the gauge NOT the motor.

Im talking about that little valve on the tip of the tester. The piece that you insert in the spark plug hole has a small valve similar to the ones you see on tires...

yea, i know what your talking about. Thanks

you mean the schrader valve.

I think he knows about the schrader valve now after 9 years.......
ಠ_ಠ

...owned

Your logic is not flawed... But your picture scares the shit out of me, -.- you should brush that hair.

if its flooded you can get a false low compression reading. pull the leading plugs, pull the "engine" fuse or unplug the fuel pump, and turn it over at WOT for 10-15 seconds and try again

This is slightly embarrassing. OP was a noob and didn't install the schrader valve.

I hope my first post asking for the "biggest loudest exhaust" don't get dug up too.
ಠ_ಠ

trolololololol

i didnt find it, so i simply bumped your first post.

fix'd