Re: v-belts

[pjrose@servtech.com (Phil & Judy Rose)]

A couple of weeks ago I posted about my '91 200q hydraulic pump producing a
chirping noise. I thought the pump drive belt seemed overly tight, so I
loosened it and applied dressing, but the squeal returned fairly soon
thereafter.

Just as Huw (and Fred) described, I noted that this (toothed) v-belt
doesn't seem to fit the pulley very well. The top of the belt is about 1/8"
_below_ the pulley's outer rim, and the belt sits askew because of
mismatched angles.

How is one assured of getting the "right" belt? A "dealer"-supplied belt
may not necessarily be the answer, inasmuch as records show the dealer
replaced all three v-belts for previous owner 16 months ago. Hence it's
probable that the present v-belt is one from the Audi (authorized) dealer.
Some months later, the hydraulic pump was replaced (at the same dealer)
with a Shokan rebuilt unit, but no belt replacement was noted. If the
present belt really is OEM, and if the pulley gets changed along with the
pump, might it be that the new pulley had *different* dimensions--not quite
matching the old pulley (and belt)?

Or do dealers just cut corners by selling a non-OE spec v-belt? Naaaaah!

Waiting to hear from Huw about "dealer item".

Phil Rose
'91 200q
'89 100 (112K, automatic, for sale)


>Date: Sat, 29 Aug 1998 20:30:37 -0400
>From: "Fred Munro" <munrof@isys.ca>
>Subject: Re: v-belts
>
>Huw;
>
>    Check the section size and shape on the v-belts you are using. The Audi
>alternator belt has a peculiar thin section which is not easily matched by
>typical North American belts. The belt should sit well down in the pulley
>with just a bit of the belt section above the pulley rim. If the belt sits
>too high, you won't have enough surface contact to handle the load and the
>belt will squeal. If the belt sits too low, it can bottom out in the pulley
>and will also squeal.
>    I have toothed belts on my 200q and have no problems. I made sure the
>alternator belt fit properly, though - I had to return the one initially
>supplied and get one with a thinner section.
>    I have seen belts with the teeth on the outside and smooth on the
>inside, but cannot recall who makes them.
>
>HTH
>
>Fred Munro

followed by:
>Date: Sat, 29 Aug 1998 21:11:41 -0400
>From: Huw Powell <human@nh.ultranet.com>
>Subject: re: v-belts
>
>I'd say Fred hit that one on the head.  just compared the shattered $5
>belt from VIP with a spare alternator pulley, it is a fatter included
>angle in the V, and sits a good 1/8" (3 mm) inside the OD of the
>pulley.  The different angle makes it not really touch the pulley
>smoothly unless it twists to touch one side.
>
>Report on dealer item to follow soon...
>
>- --
>Huw Powell


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