DavidH

I've read Dave's entire thread and having so, feel Dave is much more skilled than I at working on the 928. If Dave's stated theory is correct for his belt failure, that being the belt was too tight, (Dave stating he increased the tenstion twice over several months), my question is how is it possible to use the Kempf tool and get such poor readings on the belt tension?

DH
1989 S4

Big Dave

The readings were correct. I'm told by 928 International the the bolt probably bent due to over-torquing when the tensioner arm was installed. It likely had nothing to do with the belt's tension.

John Speake

The Kempf tool is very accurate, and easy to use. It can't be blamed if there is some other hidden problem...........

Jim bailey - 928 International

Mr Speake .....well spoken !

docmirror

Strange coinkidink, I've had massive problems with the ribbed belt on my F350 lately. Finally diagnosed to a bad tensioner bolt, very similar to the 928. Luckily, when my belt either broke or fell off, the engine didn't desintigrate. I was just left towing a giant boat down the FWY at 70ish with no PS, PB, alt, AC, engine overheating, at nite in rain. Now that'll increase the pucker factor for a few minutes. I replaced the tensioner and idler and bolts, and all is well. Damn things only lasted for 220k miles, sheesh.

Doc

Gretch

Notice that when you purchase a new tensioner for the ribbed belts that come on many cars built in the US, the kit also includes a new bolt. That tells me something, 'cause There is no way the supplier would incur such an added cost if it was not absolutely necessary.

Hmmmmmmmm

Big Dave

Perhaps a new tensioner bolt ($13) should now be added to the items that should be replaced with each timing belt change. Of course, if over-torquing is the problem, a new bolt ain't gonna help if you're over-wrenching.

Warren928

Gretch,

It sounds like the tensioner bolts are getting fatigued and stripped out or ovaled from stress. So it sounds like all ne mounting bolts are needed or just certain ones?