Broken Timing Belt

[andrewjscott]

What are the chances I bent valves with 12 broken teeth on a timing belt. Did a hand compression test and got 25psi accross the board. Leads me to believe that all are bent equally, or none are bent. All timing marks line up. I know its supposed to be 160 with a regular compression test, but does 25 seem like a reasonable number for turning it over by hand?

 

[daves06r1]

I would say if the valves are bent and not closing you would get 0 on the gauge, and also i bought my car with a blown engine nice guys at mitsu dealer didnt change balance shaft belt so it broke went between crank gear and belt and in turn skipped only a "couple" teeth and bent every intake valve.

 

[laserspeeddemon]

Ya, they are bent!

 

[drivemusicnow]

Ya, they are bent!

He's turning it over by hand.

I don't KNOW, but I think before you tear it down, put the starter on and do a real compression test. YOu might still have an acceptable reading.

 

[andrewjscott]

yeah, im gonna throw a new belt on and see what kind of compression i get with a proper test. Also i removed the valve cover and all the seating heights of the valve springs are correct, and there are no loose rockers when the valve is closed.

 

[taylork057]

if your getting compression, their not betn..your timing is WAY off..but who knows.

you wont see any comp with bent valves

 

[andrewjscott]

that was what i figured. Engine is comming out to do a tranny rebuild anyway. Thanks for the assurance

 

[andrewjscott]

So its all pulled apart and I think i found why my car ate its timing belt. The crank sprocket had 2 different teeth cracked, both around the bolt holes, looks like it was overtightened.

 

[laserspeeddemon]

He's turning it over by hand.

Ohhhhhhhhhhh, I didn't see that. Thats what I get for scanning over the post.

 

[90_EAGLE_TALON]

You can get compression and still have slightly bent valves. I had that happen to me on my 90 talon about 2 years ago. If you are taking the engine out anyway I would say pull the head and double check and put the new headbolts in it. Better safe that having your car burn oil and lose soem power.