Re: Vacuum hose question

[quk@isham-research.demon.co.uk (Phil Payne)]

In message <19981010214117.3988.rocketmail@send1e.yahoomail.com> Dan Murphy writes:

> Hey all, I think my problem with my 85 cgt is the vacuum.  I'm not
> getting any at some places and all the hoses look real bad.  I'm
> planning on just buying some hose and replacing all the vacuum hoses I
> can.  But i went to Champion Auto parts today and they said I had to
> know what size the hose is.  I have no idea what size it is.  So, does
> anyone know what size it is?  Or where I can get like 10 feet or so of
> vacuum hose?  Thanks.

It's nominally 3.5mm ID.  I use Gates 3225 4mm multi-fuel hose, secured
with proper hose clips.  Costs pennies a foot, compared with AUDI's
quite frightening price.

Most common vacuum problem I find on those cars is a ruptured vacuum
advance diaphragm.  Second most common is the hose chafing through where
it sits on a wiring bundle at the back of the head.

I'd guess about one in three of the cars of this age I see has a vacuum
fault.  The MityVac is one of the first things I use on most of the 
engines I see.

My Passat had a faulty vacuum advance system for eight years.  Just after
John Robinson sold it to me, I did the MityVac test and it failed.  So I
debugged it and found the bad diaphragm.  Naturally, once the leak was
stopped, all of the other vacuum operated bits started working again,
including the upshift indicator.  I asked John when it had stopped 
working, and he said: "What upshift indicator?"
 
There's a distinct possibility (he had the car from 8000 miles) that it was
bad from the factory.

--
 Phil Payne
 Phone: 0385 302803   Fax: 01536 723021
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