Air Conditioner clutch vibration

[mistral2099 Lurker Find all posts View Profile Close mistral2099]

2001 Prado 3-litre turbo-diesel TX auto. Recently was noticing an unusual sound in the engine when I switched on the A/C. Opened the bonnet to have a look around and first noticed a maroon red powder all around the engine bay, seeming to come from the front of the engine compartment somewhere. Looked further to discover one of my alternator belts broken and lying in the lower metal protector trays.

Got replacement belts for all three belts and installed them, noting as best I could the approximate tension settings. (Guy at the parts store reckoned that the belt that broke had NEVER been replaced since the vehicle was delivered...)

Now noting that when the AC is off everything seems fine but as soon as I switch on the A/C there is a terrible vibration in the A/C clutch along with a nasty noise -- appears there is an excessive amount of play in the bearing on the pulley on the front of the compressor.

Any thoughts on what the next step should be? What can be repaired? Is it necessary to replace the compressor, or can it be repaired without removing it? Any thoughts on what an estimated cost to repair will be?

This is the very first thing that has EVER gone wrong with this vehicle in 10 years. Replace oil every 5,000km, replace tyres, replace brakes, replace filters and it just keeps going. Awesome.

Here are two videos: First with a/c off, second with a/c on.

A/C Off: http://www.youtube.com/watch?v=xCs3kOteG-c
A/C On: http://www.youtube.com/watch?v=N6tblNYy294

Here's the red dust.
http://www.kitesurfing.com.au/red_dust.htm

[Matty80 Avid PP Poster! Find all posts View Profile Close Matty80]

Re: Air Conditioner clutch vibration

I'd guess that the red dust could be from the moments just prior to the old belt snapping or from the internal clutch mechanism of the compressor?
Where it is possible that something seized within the compressor (collapsed bearing???) and caused the pulley to stop rotating or the compressor to stop???

More likely the compressor stopped! Excessive wear occured on the clutch - excess dust? - and due to the motor running the belt gave and possibly the clutch...
Now you say that there is excess play in the drive end of the compressor? Definitely sounds like it requires new bearings and probably a few other items as well.

Either way - due to the continuous rotating nature of sections of the compressor mechanism while the engine is running, regardless of AC being on or not - I would advise getting it back to a repairer asap, as smaller issues tend to grow into big ones quite quickly with rotating machinery.

Don't be surprised if its a complete rebuild or replacement

Matt

[Derb Senior Member Find all posts View Profile Close Derb]

Re: Air Conditioner clutch vibration

Hi Mistral. Red dust would be "Fretting" caused by metal to metal friction. Can be caused by bearings worn and slowly grinding down to their base element or friction between imperfect/loose fit on iron components. I would have a good look at the bearing in the centre of the aircon clutch. Cheers, Derb.

[mistral2099 Lurker Find all posts View Profile Close mistral2099]

Re: Air Conditioner clutch vibration

Thanks guys. The compressor is still working, albeit with about 2-3mm of play in the compressor shaft--but you don't see the play until you engage the A/C clutch when you turn on the A/C. Otherwise everything seems entirely normal. I'm inclined to think that the red dust might be coming from the bearings rather than the belt, as the belt was black and I couldn't see anything anything in the belt that looked that colour.

Reckon it'd be best to take it to the Toyota dealer or to a specialist A/C repairer to get it looked at?

Derb and Matty&Loz, many thanks again for your feedback.

Rob.

[mistral2099 Lurker Find all posts View Profile Close mistral2099]

Re: Air Conditioner clutch vibration

Just back from the A/C repair place. Looks like the internal bearings on the compressor are gone. Cost for a new OEM unit installed: $918 or re-manufactured unit for $816, so not as bad as I expected. I suspect the origin was when I last took it to the dealer for service about a year ago and they neglected to check the belts and they were still slipping and squealing when I got it back,(I asked them to do so on the service, but they ignored me) so rather than wasting another half day to take it back I tightened the pulley to stop the squeaking -- perhaps too much. Now the bearings are shot. Dealer should have replaced the belt and adjusted the tension--they didnt--so their incompetence on what would have been a 5 min job to fix turned into a $1,000 cost for me in the end. Bugger.

Oh well, I suppose it could have been a lot worse.

[croozza Avid PP Poster! Find all posts View Profile Close croozza]

Re: Air Conditioner clutch vibration

Just back from the A/C repair place. Looks like the internal bearings on the compressor are gone. Cost for a new OEM unit installed: $918 or re-manufactured unit for $816, so not as bad as I expected. I suspect the origin was when I last took it to the dealer for service about a year ago and they neglected to check the belts and they were still slipping and squealing when I got it back,(I asked them to do so on the service, but they ignored me) so rather than wasting another half day to take it back I tightened the pulley to stop the squeaking -- perhaps too much. Now the bearings are shot. Dealer should have replaced the belt and adjusted the tension--they didnt--so their incompetence on what would have been a 5 min job to fix turned into a $1,000 cost for me in the end. Bugger.

Oh well, I suppose it could have been a lot worse.

Have you got the compressor yet, if not check the price with toyota (and ring a few to get a good price) I did this about 18 Months ago for mine (abeit a Petrol version Prado, but the part might still be the same) and the fitted price by toyota was $600.00.

[mistral2099 Lurker Find all posts View Profile Close mistral2099]

Re: Air Conditioner clutch vibration

Local A/C place did a great job on it on Tuesday. They got a new compressor (which was only $100 more than a reconditioned one).Full cost of parts and labour including a full regas and drier replacement came to $1,100. It works better than it did when new now. Not cheap but they did a really good job. Grady's Auto Electric in Brookvale. Good people. http://www.gradysauto.com.au/