12 replies to this topic

[kopi]

Hi all. I have a '92 SPI with air conditioning. I can't seem to solve the problem of a squealing belt whenever i switch on the air conditioning.

Initially, I had a 45AMP alternator, but a couple of drained batteries later i've decided to change the alternator

Bought the 70AMP from minispares, advertised to work with SPIs. However the belt keeps slipping. Brought it back to a workshop, got the belt replaced or tightened several times and the problem goes away for awhile. But after that, belt slips again in like 2-3 weeks of light driving.

What should I check on? There aren't that many mini mechanics where I live and i hesitate to bring the mini to a regular workshop.

Should i get a new alternator? Is it a misalignment? I can't be changing belts every month or so. What is the primary reason the belt slips?

Thanks for any suggestions!

[tommy1275auto]

hi kopi im having the same prob at the moment iim in 96 mayfair and the squaling is terribly annoying i havnt air con but if anyone has ideas id love to know aswell as im replacing the belt tomorrow anyway as it just snapped, cheers

[Beej123]

Check the pulleys are clean and free from grit or paint and check that the altenator is secure in its mounts, it may be loosening the belt off as you use it.

[kopi]

Thanks Beej123. I have and do check that regularly.

I'm suspecting if the belt can't grip the 70AMP alternator pulley well enough because of the power it needs to generate, hence the slippage.

If I were to toy with a complete different alternator setup, including porting those not native to minis, would that work? Any recommendations?

[Beej123]

The power of the altenator shouldn't make any difference because its not that that drives the belt, some altenator manufacturers offer different pulleys so it may be worth having a look to see if there is a part you can buy before outlaying the money for a whole new altenator.
I thought the pulley was different on the injection models so it might just be a simple pulley change.

[Carlos W]

Have you still got your old pulley?

Can you compare it to the new one?

[icklemini]

The bigger alternators do put more load onto the belt - simply because they are 'heavier' to turn.

Check that all the pullys are aligned, check the pullys for wear too, get a good quality belt and adjust it so you can *just* turn it through 90degs on its longest span.

[kopi]

Thanks for your suggestions.

How can i confirm if its the alternator pulley thats causing the problem? I traded in my old alternator so its gonna be tough to compare.

Intuitively, i agree with you icklemini. Guess if i have to find something in-between ... like a 60-65AMP?

[Manuel B]

The alt. pulley on my '93 with A/C is 24mm thick, the belt rides flush with the outer edge of the pulley, if your pulley is too wide maybe the belt is not being squished between the sides and is riding on the bottom of the V ?,  Alt._pulley.JPG   135.57K   10 downloads

[xrocketengineer]

Hi,
Carefully inspect the belt, pulleys on your old alternator, new one and the compressor clutch. Makes sure that the "V" angle matches in all of them. Not all pulleys and/or belts have the same angle. They must match for proper operation. I had a VW van that I bought used with an aftermarket air conditioning system. The air con belt would get destroyed every 3 months or so. Finally, a friendly auto parts store guy figured out the problem. If my memory does not fail me, the standard belt "V" angle was like 38 degrees. I needed one with something like 42. That solved the problem. The narrow belt was contacting down at the bottom only and not on the sides as it should.

Ivan

Edited by xrocketengineer, 02 May 2011 - 11:54 PM.

[kommander]

Has anyone solved this problem? Other SPi owners including myself have the same issue. I bought the original belt from Japan and it hasn't solved this.

 

Is it possible to change the pulleys and convert to the single belt setup like the MPi?

[kommander]

Bump....any solutions?

[Alpenflitzer]

I do not have AC but had the same terrible squeaking. After several tests I bought a brandnew belt - the old one was as a spare in my workshop  and began to glassify i.e. gets hard and has a slight shine.

Then I found out that between the two pully wheels there was a slight difference when you checked with a metal ruler. Sop the belt was not correctly in the V-shapes.

Since then not noise anylonger.