PAS pump noise

PAS pump noise

Author
Discussion

andymadmak

Original Poster:

14,597 posts

271 months

Tuesday 10th December 2002
quotequote all
The PAS pump on my 91 400se has taken to screaming when it gets hot and is asked to do something big (like tight turns etc).
I really don't think it's the belt cos the noise it makes is wrong -it sounds/feels sort of mechanical rather than a slipping belt squeel, plus you can vary the intensity and pitch just by tweaking the lock a bit, and it will even do it in the straight ahead position for a while when it gets VERY hot!
Does anyone know what this means cost wise? Is it just new seals or a total rebuild (assuming kit available + it's easy enough for my limited mechanical ability) or is it a new pump job? If so, anyone know what kind of pump it is? (its painted mid blue colour, and has a long filler neck!
Questions questions eh?

Andy 400se

bobfrance

1,323 posts

268 months

Tuesday 10th December 2002
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I take it you've checked the fluid levels in the pump?

Mine made a (droning)noise on full lock when it was low on oil - topped it up and it's fine.

andymadmak

Original Poster:

14,597 posts

271 months

Tuesday 10th December 2002
quotequote all

bobfrance said: I take it you've checked the fluid levels in the pump?

Mine made a (droning)noise on full lock when it was low on oil - topped it up and it's fine.



Sadly yes. Fluid good (if a little black... shouldn't it be red?)
Andy 400se

350matt

3,740 posts

280 months

Tuesday 10th December 2002
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Errm yes
Try changing the fluid (ATF) and then see what its like, also you can get some stuff from Halfords et al to shut up noisy PAS pumps which I've used before.
It sounds like you've got a Rover SD1 pump fitted from your descrption so 10 quid from the scrappy?

Matt

>> Edited by 350matt on Tuesday 10th December 12:36

wedg1e

26,805 posts

266 months

Tuesday 10th December 2002
quotequote all
I pulled a spare PAS pump (of the same design as the one on my car) apart - I was bored - and there's not much that could go wrong.
The main casting is a push-fit into the pressed-tin body, with an O-ring seal, and one bolt holding it in from the rear (where the pipes connect).
The pulley shaft turns a hub in an eccentric chamber. The hub has about a dozen slots cut along its length; in each slot sits a steel roller. There's a magnet to catch ferric swarf. The rollers propel the PAS fluid around, pressurising it. As the whole thing is virtually an ideal environment (totally immersed in lubricant) it would have to be a big piece of debris or being run for a long time with no fluid, before it would get miffed. Could be the shaft bearing is kaput.

Ian

andymadmak

Original Poster:

14,597 posts

271 months

Wednesday 11th December 2002
quotequote all
Thanks for the info.
I'll have a look over the winter!

Cheers
Andy