Air conditioning compressor, rocket science?

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Jul 12, 2007
Norcal, not on fire but it was darn close.
A local small town garage said they can put mine in for $150 to $200.
As I don't have a vacuum I cant do this my self.

So its to sick to drive to the next "big town" can a local shop do this on a FJ80 or is there something mystic I need to know?
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Not rocket science. Diagnosing the AC is the hardest part.

If you can change the compressor yourself you can pick up a vacuum pump on Amazon for about $60. This is what I use:

TMS® 3 CFM Single-stage Rotary Vane Vacuum Pump R410a R134 Hvac A/c Air Refrigerant

Loan an AC manifold set from the auto store or pick up a set from harbor freight for $55. Then pick up 3 cans of r134 from Wally World at $5 each.

You'll need a few extra parts. Coupler to pierce the can of refrigerant and another coupler adapter that connects the vacuum pump to the AC manifold.

All less than $200 and you can pull vacuum if you have another leak in the future.

Change the drier since you're opening the system and add pag oil too.
Typically replacing a compressor and drier at a shop runs $500+. A new Denso compressor runs about $200, plus the drier, o-rings, refrigerant and labor makes their price seem way to cheap. What happened that you need a compressor?
I picked up a Denso compressor from Rockauto, a drier and expansion valve from Ebay. The compressor was $200 but the drier and expansion valve were $9 and $7 respectively. All the parts came with o-rings.

Changing the compressor is easy and most come pre-oiled. But, getting the expansion valve out was a PITA. I think I either watched a video or found pictures online on how to remove the evaporator coil and expansion valve. Verify that your high and low shrader valves on the compressor are not sticking out too far and causing a leak.

Once the new parts are in, I borrowed a vacuum and manifold gauge set and started pulling vacuum. Pull vacuum close to 30. BTW, you know the vacuum is working because it will be loud. Once it pulls full vacuum the noises will lessen. Shut off the vacuum, confirm the gauge reading, and walk away for 30 minutes. If the manifold gauge reads the same, you are golden and ready to add refrigerant.

BTW, examine the AC belt while you are at it and verify proper tension.

How much pag oil?
Per the FSM
What year? I can't speak to 91-92 but on 93-97 you can remove the AC belt pretty easily and drive it that way. Won't impact water pump or alternator operation.

Even if you don't want to do that.. the compressor can be bad but as long as the pulley still spins free with the clutch disengaged (AC switch OFF) you should be able to drive it all you want. Now if the bearing in the pulley is bad or noisy, the belt needs to be removed.
Cut the belt. That's pretty easy, and they're relatively cheap to replace.

But, removing it the right way isn't too bad either - the idler/tensioner assembly can be reached from underneath the truck. Loosen but don't remove the bolt in the center of the idler pulley (when tight, this bolt locks the assembly in place) and then loosen the long adjuster bolt behind the bracket until there is enough slack to remove the belt.
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Hi I redid my system. Its not cool when Im parked. It needs pretty good RPM and then its an ICE BOX even over 100F its a FREAKING ICE MACHINE. sorry good use of caps.

Should it get cool when parked?
If should stay cool to cold-ish if the fren charge is just right and your cooling system is working well.
new condenser or is that a dryer filter.
parked my fan clutch appears to run.
iv found most all mechanics to be kind of rude or stupid so doing it all my self now.
"yeah cant do it for weeks and its guna be expensive"
new condenser or is that a dryer filter.
parked my fan clutch appears to run.
iv found most all mechanics to be kind of rude or stupid so doing it all my self now.
"yeah cant do it for weeks and its guna be expensive"
maybe try the newspaper trick... roll up a newspaper and stick it in the fan slowly, if it's super easy to stop, clutch may be shot...

mine was, just replaced it with an amazon blue hub and i've been good to go for a year or so now... if you want to go the premium route, there's always landtanks modded stuff that joey sells

also, mine do the whole "busy and not work i want to do" thing too, it's kind of irritating...
As mentioned, fan clutch. Possibly loose fan/alternator belts.

When parked there isn't enough air moving through the condenser core in the front of the truck to actually cool the refrigerant that the compressor is pushing through. Give it revs or drive it down the road: enough air, so FREAKIN ICE COLD A/C.

Your truck is probably running somewhat warm at low speeds as well, for the record.

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