so for the past couple months my ac has a squeal every once in a while. noticed the tensioner was loose, didn't fix it in time and the whole pulley flew off, lesson learned. replaced with brand new tensioner pulley and also ac compressor belt, but the squeal still happens. its definitely coming from the ac because whenever its off it doesn't make noises and when its on it sometimes squeals and when I turn the air conditioning off it immediately stops. again it sounds like a belt but that's brand now, so I doubt it. any ideas? 94 kzj78, 1KZ
kzj78 ac squeal
- Thread starter Maccuscharlie
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Make sure your belt tension is adjusted correctly according to the manual. Incorrect tension will cause belt squeal.
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- #3
Any idea what the correct tension would be? I’ve got the 1kzte manual for a hilux but not the kzj78
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- #4
After examining it more, it’s most likely not coming from the actual belt. Because the belt constantly spins when the engine is on. The noise stops when I turn the ac off, but the belt is constantly spinning. Im guessing the noise has something to do with a bearing on the actually ac compressed itself, but not sure
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- #6
Coming from the engine bay, the blower motor was just replaced a few months ago and sounds fine
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- #8
Does anyone know if this section I marked red is supposed to spin or not? Mine doesn’t, but every once in a while it spins a little
IIRC that portion only spins when the AC clutch is engaged, if the AC is off it shouldn't spin.
The reason you're only getting belt squeal when the AC is engaged is because that is the only time the belt is having to transmit any power, if the AC is off the belt isn't under load and therefore won't be slipping. On my VW Jetta the alternator belt squeals badly on startup, because it has to spin up the alternator under load.
The reason you're only getting belt squeal when the AC is engaged is because that is the only time the belt is having to transmit any power, if the AC is off the belt isn't under load and therefore won't be slipping. On my VW Jetta the alternator belt squeals badly on startup, because it has to spin up the alternator under load.
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- #10
That may be my problem, it seems to be stuck
Double check the pressure in the AC system as well. It could be over pressuring or under pressuring which could also cause the sequel
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- #12
How exactly do I check that?
If you don't have a set of AC gauges then any GOOD AC shop could check it for you.
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- #14
Narrowed it down to what I believe is the magnet clutch on the front of the ac compressor? It doesn’t spin when the ac is off (normal). When ac is turned on it starts spinning (again normal), but right when the squeal starts, it looks like it’s getting stuck on something, it’s slows down a lot and I believe the squealing sound is coming from there. Tried adding lubricant and isn’t any better. Does anyone know if this could simply be a bad bearing, or is it more likely something to do with whatever mechanism is supposed to be engaging it when the ac is turned on/off?
Here are the part numbers for a 1995 KZJ78
jp-carparts.com
HEATING & AIR CONDITIONING - COMPRESSOR / toyota | part list｜JP-CarParts.com
toyota・LAND CRUISER S/T,H/T・HEATING & AIR CONDITIONING - COMPRESSOR parts catalogs with pictures.You can find the parts you want.
Did you had any work done on the A/C system prior to the squeal starting? From the description, it has the characteristics of the system being overcharged.
The other possibility I can think of is that the clutch gap, the space between the front hub and the pulley, is incorrect, it should be about the thickness of a matchbook cover,
Also, there's nothing you can lube externally that will help and the hub and pulley depend on metal to metal contact, so lube in there isn't good.
The other possibility I can think of is that the clutch gap, the space between the front hub and the pulley, is incorrect, it should be about the thickness of a matchbook cover,
Also, there's nothing you can lube externally that will help and the hub and pulley depend on metal to metal contact, so lube in there isn't good.
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- #17
Blower motor died and ac wasn’t turned on for about 2 months. The noise started immediately after replacing the blower motor and starting it up again for the first time. Not sure why sitting off would cause it to do this
Is the belt tight? My mothers Datsun did this once, but she didnt use the aircon for a year or so and it seized up. It could be that your compressor clutch was on its way out anyway
I assume the A/C worked fine before the blower died? Any chance you could hook up some gauges so we could see what the system pressures are?
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- #20
Correct ac worked fine before blower went. Hm I don’t own the tools to do that, may just take it somewhere to see what they say
