NH Pajero AC Belt

[xboxice]

A bit hard to see, but I think that the pulleys are probably aligned OK. Certainly unless you have changed the mounting brackets, they should still be in line.

You tried turning the pulley whilst the engine was running. The part you were turning will always turn - with or without the A/C clutch being engaged. The bit to check it the centre of that pulley - does that turn OK when you have the A.C turned on? The clutch engages the central part of that pulley and then turns the compressor. The bit you were turning by hand always runs. I suspect that the central part of the pulley may be locked solid ie the compressor has seized internally. Was there any significant resistance as you tried to turn the pulley?

Yeah i little resistance but not much at all

[alchemysa]

A bit hard to see, but I think that the pulleys are probably aligned OK. Certainly unless you have changed the mounting brackets, they should still be in line.

The fan pulley looks shiny indicating the AC belt is rubbing. (Look at the shiny rings around the bell shaped pulley). This may not be apparent until the AC is ON and the engine revs are high. This may be the source of the burning smell and ultimately the belt failure.

This is what I was talking about in an earlier post. What size belt are you going to install next time? You may need to get a belt 1 cm shorter than previously.

[Roach]

Before the belts snapped did your aircon work well or just ok? Did it actually work at all? Also check gas. If its short of refrigerant the compressor won't get any cooling back to it. so when it's hot bearings wear and could possibly start to seize causing belt to snap. Does the clutch on the front of compressor disengage when ac button off and engine running?

[alchemysa]

The fan pulley looks shiny

The pulley is shiny because the AC belt running from the crankshaft (A) to the AC tensioner pulley (B) is rubbing on it.

[xboxice]

The fan pulley looks shiny indicating the AC belt is rubbing. (Look at the shiny rings around the bell shaped pulley). This may not be apparent until the AC us ON and the engine revs are high. This may be the source of the burning smell and ultimately the belt failure.

This is what I was talking about in an earlier post. What size belt are you going to install next time? You may need to get a belt 1 cm shorter than previously.

Awesome,i was told the same thing by my mechanic m8 to get a smaller belt.

[xboxice]

Before the belts snapped did your aircon work well or just ok? Did it actually work at all? Also check gas. If its short of refrigerant the compressor won't get any cooling back to it. so when it's hot bearings wear and could possibly start to seize causing belt to snap. Does the clutch on the front of compressor disengage when ac button off and engine running?

HI yeah works perfect until belt snap.

[xboxice]

Before the belts snapped did your aircon work well or just ok? Did it actually work at all? Also check gas. If its short of refrigerant the compressor won't get any cooling back to it. so when it's hot bearings wear and could possibly start to seize causing belt to snap. Does the clutch on the front of compressor disengage when ac button off and engine running?

And yeah disengage when ac off and can spin freely

[xboxice]

The pulley is shiny because the AC belt running from the crankshaft (A) to the AC tensioner pulley (B) is rubbing on it.

what ill do is try and get a different belt then have someone rev engine and ill have a look,or maybe test with the same belt to see see if it really rubbing

[xboxice]

Thanks guys for all your help,i think the belt was rubbing on fan bell housing,when installing ac belt it has to be tension right up so when engine rpm rise the belt doesn't flex out and rub, at this point i'll keep my eyes on the tension to see if its changing over time which i think is happening.

[alchemysa]

Thanks guys for all your help,i think the belt was rubbing on fan bell housing,when installing ac belt it has to be tension right up so when engine rpm rise the belt doesn't flex out and rub, at this point i'll keep my eyes on the tension to see if its changing over time which i think is happening.

The problem is that tightening the belt actually worsens the problem. Tightening it moves it closer to the fan bell housing.

I had the same problem with what I believe was the original factory fitted belt. The only solution was to get a slightly shorter belt.

[sparkymizzo]

the tension pulley may need a new bearing, or the compressor bracket may be loose.

[xboxice]

The problem is that tightening the belt actually worsens the problem. Tightening it moves it closer to the fan bell housing.

I had the same problem with what I believe was the original factory fitted belt. The only solution was to get a slightly shorter belt.

Do you have part # for the shorter belt

[xboxice]

the tension pulley may need a new bearing, or the compressor bracket may be loose.

i have installed new pulley
and it spins freely

[alchemysa]

Why did you install a new pulley?

Anyway, the belt I have on now is a 13A 0940 meaning it is 940mm (94cm) long. Its just a belt from Supercheap. I just grabbed it when I went past supercheap one day, and used the recommended belt from their Gates book. It has about 1 cm of clearance between the belt and the underside of the fan bell pulley. I reckon if I planned it better I could have used an even shorter belt, say 93 cm.

I don't know how long the old belt was, its been lost, but it was definitely rubbing on the fan bell.

Whats the number on your new belt?

Belts are measured on the inside. The outside measure is usually 2cm longer, so a 94cm like mine belt is actually 96 on the outside.

[erad]

i have installed new pulley
and it spins freely

The pulley itself will spin freely - until the compressor clutch is engaged. Then it will test if the guts of the compressor are seizing up.