944 with jumped/broken timing belt

[dfwdiesel]

We are looking at buying an 84 Porsche 944 with the timing belt intervel is no doubt past due.

We have done this job successfully on our driver 924S. (It was started to verify it ran, then sat until

be did the belts, idlers, and water pump.

Curious about the odds on the valves are damaged, as we have a known good 944 head.

Looks like a reasonable project if the lower end is still OK.

What are the odds only the head is damaged vs the pistons, rods etc also. My guess is if it happened at idle, maybe we could be fine with the head. Running at high RPM may need a replacement used engine, not so easy to find and pencil out.

What do seasoned enthusiasts say?

John Gregg

[racer212]

I'm certainly no expert,but I'm in the midst of replacing the belt on my 83 model. According to my mechanic (who is a Porsche guy) the belts usually fail at startup. According to him most of the time you destroy valves, and the pieces fall and tear up pistons and rings.

I bought a car that allegedly had the belt done 32k miles ago. I had it opened up to adjust/replace and sure enough my belt was missing 5 "teeth" on the cam belt. Paul, my mechanic, said I was probably less than 10 starts from complete belt failure! glad I listened to everyone here and just got it done.

:renntech:

Edited January 10, 2008 by racer212

[magcuda]

you can't try to stretch out the mileage on these belts, just won't do it

to the head, what year is the head from? the early heads and late heads have different combustion chambers

[roadracer311]

We are looking at buying an 84 Porsche 944 with the timing belt intervel is no doubt past due.

We have done this job successfully on our driver 924S. (It was started to verify it ran, then sat until

be did the belts, idlers, and water pump.

Curious about the odds on the valves are damaged, as we have a known good 944 head.

Looks like a reasonable project if the lower end is still OK.

What are the odds only the head is damaged vs the pistons, rods etc also. My guess is if it happened at idle, maybe we could be fine with the head. Running at high RPM may need a replacement used engine, not so easy to find and pencil out.

What do seasoned enthusiasts say?

John Gregg

I don't know if the 924 and 944 have similar amounts of valve to piston clearance, but I had a belt let go on a 1979 924, replaced the timing belt and put on at least another 10k miles without a problem before I sold it.