dredpyrt

Finishing up the TB/WP on my 86 and i've come to the point where its time tension the menagerie of belts on the front of my engine. How much slack/deflection should i shoot for?

the flyin' scotsman

work shop manual suggests 10mm......alternator typically tighter

dredpyrt

Thanks!

WallyP

That applies to V-belts. The flat polyrib belt goes tight.

DZGunner

How tight...

jcorenman

You're not going to like the answer... 9.2 BU's (belt-units) for a new alternator belt, measured with the factory 9201 belt-tension gauge per page 13-18b of the WSM, '82 onward. Used belts should measure between 8.4 and 9.2.

I think a good estimate is tight enough so that you can just twist the belt 90 degrees with thumb and index finger. YMMV etc.



Cheers, Jim

Avar928

Rule of thumb is you can bend the belt 90 degrees and no further. I'd stick with that.

DZGunner

Ok, figured i'd ask, i'm doing my belts now.

jcorenman

Here's a quick vid of checking the alternator belt-- including a "twang" on the belt which might be a useful reference.

the flyin' scotsman

sounds like E flat Jim

syoo8

Actually, the pitch Jim "plucked" with the belt was a G natural, but slightly sharper than a G natural.

jcorenman

You're saying that my alternator is out of tune? Oh great, now I have to get a piano for the shop...

syoo8

Actually, European orchestras tune to a higher A, around 443-445 Hz (as opposed to 440-441 here in the US) so your alternator is perfectly in tune for a German car.

Wisconsin Joe

You do realize that you are way too cultured for this band of miscreants, don't you Mr Yoo?

BTW, absolutely incredible work on your intake refresh and TB/WP threads. Both the actual work on the car and the documentation in the threads. Comparable to Dwayne IMHO.

syoo8

Ha!

Thank you Joe. Of course, Dwayne's work is an order of magnitude more accomplished than mine... I am just a (bad) copy.

Holiday cheer to all!