Air Con compressor bearings going ?

[VladTepes]

Has anyone had the bearings on their Air Con compressor fail?
Does it make a horrible grinding noise, most of the time ?

I have a suspicion that the latest noise from my ute might be just that. Nothing else seems to be wrong (some minor overheating which I first thought was connected to the noise, but now I don't think is related - water pump seems fine).

Does the air con compressor on the these engiones (300Tdi) work by having the belt drive the pulley all the time, and when turned it engages some kind of clutch in the compressor?

How would I tell if it is the air con compressor? As far as I can see I;d need to remove the belt? The belt seems to go over a number opf various pulleys, but am I right in saying that particular belt has not purpose other than the air con?

The main serpentine belt is in front of it, of course, so it appears I'd need to remove that first in order to get to the air con one.

Is this an easy job?

How would I go about removal and refit of these belts - if in fact that's what I should be doing?

Please help. I hate unknown noises.

[VladTepes]

OK having just read another thread it seems there is another possible suspect.
Seems the idler pulley could be the culprit ?

I'd appreciate if those with knowledge of the matter would elaborate further on how I'd go about checking / fixing.

[bee utey]

Rather than a specific reply aboout which bearing might be the one, I suggest you use a piece of hose as a stethoscope. Just make sure it isn't swallowed by one of the belts.Then try removing a belt or two and spinning the now free pulleys to confirm bearing failure. Removing/replacing a belt is a skill you should have as a concerned LR owner.

[one_iota]

Hi Vlad,

I replaced the bearings on both the tensioner idler and the AC pulley a couple of times in my Disco days. The first time the AC pulley seized the belt broke and severed the wiring to the AC clutch so don't let it go for too long.

It could be the water pump pulley bearing as well.

The first thing is to check for the source of the noise:

A very large screw driver can be used as a stethoscope. Whilst the motor is running put the tip on stationary metal close to the pulley and the end of the handle on your ear. Obviously be careful doing this. You should hear the grating of the faulty bearing.

Failing that remove the belts (I presume you have a RAVE manual) and spin the pulley and feel for roughness.

Replacing the offending bearing in the pulley can be tricky (see recent post on circlip removal
http://www.aulro.com/afvb/technical-chatter/117565-damn-circlip.html) but for the $10 for the cost of a bearing its worth having a go at.

[VladTepes]

Dumb question(s) on account of can;t find my RAVE disc at the moment....

Which pulley is which ?


There is a smooth one immeditaly below the air con compressor, which looks like a tensioner to me ( ? ). I assume it should spin freely with the belt but it appears to be not moving AND it is very hot (as compared with a large smooth one on the main belt, whatever it's called). I presume the heat has built up due to the excess friction from the belt rubbing against a stationary pulley thingy.

If that's the culprit it looks like the one relatively easy one to replace ?

Is it a matter of getting the whole pulley or do the bearings come seperately and need to be packed with grease etc?

Thanks

[bee utey]

Dumb question(s) on account of can;t find my RAVE disc at the moment....

Which pulley is which ?


There is a smooth one immeditaly below the air con compressor, which looks like a tensioner to me ( ? ). I assume it should spin freely with the belt but it appears to be not moving AND it is very hot (as compared with a large smooth one on the main belt, whatever it's called). I presume the heat has built up due to the excess friction from the belt rubbing against a stationary pulley thingy.

If that's the culprit it looks like the one relatively easy one to replace ?

Is it a matter of getting the whole pulley or do the bearings come seperately and need to be packed with grease etc?

Thanks
Ooh, seized pulley bearing. Now the pulley will have to come off, inspected for damage, and if the pulley is OK the bearing might be all that's needed. These are usually sealed bearings and are pre-packed. But I would budget for a new belt as well seeing as they aren't supposed to drag across a stationary pulley.

Sounds like you should be paying a visit to the LR mechanic. This query makes me think you are not handy with spanners...

[VladTepes]

I certainly isn'f handy with spannas but I done good at ingalich gramma.

:lol: Seriously though, I don't have much experience in the area but am always happy to learn. If it's not too hard to do... ?

[VladTepes]

anyone got a diagram of the front of the engine that shows what all the pulleys are ?

[one_iota]

Vlad,

Two pages from the Workshop Manual attached.

First ("page 397") shows the AC compressor belt and pulleys. The tensioner pulley fits your description above.

Second ("page 432") shows the auxiliary belt and pulleys including its tensioner. This belt will have to be removed first.

HTH

[VladTepes]

I recko I could have a go at this myself howver I'm opressed for time so M..R. are going to do this job for me. Thank all for your info - I'll let you know how it turns out.

[VladTepes]

Turns out there were two pulleys (the tensioner and the idler) that were buggered – the bearings in one screaming like a bastard !

All good now - only making the "udual" Defender noises


(and thanks to the voucher I got from the club as noted previously) I was only out of pocket $27 this time !

Oh and I saw "Doris" - my old 200Tdi single cab Defender at M.R. as wll !