CHECK your AC bearings

[crushers]

so last fall i am driving my DD and i hear this squeal ...WTF?
i get out and check the belts and everything seems tight as it should be and figure i will check it in depth when i get back home.
i drive another 5 mins and arrive at my destination and as soon as the engine drops in rpm the squeal comes back worse than before.
before i can shut it down, something siezes and smoke comes pouring out from under the hood.

i raise the hood to find the AC elecric clutch has melted and the belt has burned through.

end of the year, fix it next year.

well next year is here and with the hard top installed AC makes even more sense so off i go to the local AC small motors guru with spare AC pump in hand as well as a new 12V electric hub.

we take the pump off and get the old melted clutch off the old pump and he shows me the damage:

 

[crushers]

seems that when the bearing begins to go the few thousand clearences disappear and the case rubs which generates heat. the heat then can cause the damage.

with the damage to this one we decided to check out the other used unit i had brought with me. he spun the pulley wheel by hand and it spun with no resistance. i thought "good" but then he takes the new electric hub out of the box and gives it a spin and shows me that a hub that spins easily is on its way out. once that spins with slight resistance is what a person looks for.

we took the new 12V hub, replaced the electric coil with the used one from the 24V unit and install this onto the used compressor. total cost was a used unit (free off the old PZ parts truck), new electric hub ($320 plus shipping) and $60 labor.

he went on to mention that when you change the timing belt it is a good time to check the bearing in the AC unit. a new unit is $1400, even $380 hurts but a new bearing is about $95 plus an hour to install. you don't need to crack the lines to replace a worn bearing but if you have to replace the compressor then you can add the freon charge to the price.

to test:
remove belt
spin the hub pulley, if it spins easily or rotates more than a couple rotations or makes ANY sound then replace the bearing. if it stops rotating in the first couple rotations then all is well and proceed.
once tested then reinstall the belt to the PROPER tension, DO NOT over tighten or you strain the AC bearing.

i have the bearing number in the shop and will post it up tomorrow.

cheers

the heated and cracked clutch disc material and what it shoudl look like

the scoring on the inside of the hub.

 

[crushers]

random pics of the damage ...

 

[Gun Runner 5]

I thought it was -40 degrees up there year round thus no need
for A/C.
......1978HJ45
** Are you not one of the gentleman who recommended removing the A/C from all LJ78's?

 

[4WD Toyota Owner Magazine]

Great post! Thanks Wayne.

 

[crushers]

yep, i am one of "those guys" recommending getting rid of the AC IN A LJ78 or KZJ78 but this is a PZJ70, a real truck.
<sheesh>

David, i like to help.

 

[1972FJ55]

FWIW, I have a short video on replacing the compressor clutch bearing on Denso compressors.

 

[Gun Runner 5]

yep, i am one of "those guys" recommending getting rid of the AC IN A LJ78 or KZJ78 but this is a PZJ70, a real truck.
<sheesh>

David, i like to help.

The LJ78 is first referred to as the "poor mans Cruiser" and now it not even a "real truck".
Man I am glad I sold that sucker.
......1978HJ45

 

[crushers]

now, come on, don't take the post out of context.
i didn't say the LJ wasn't a real truck ...
















or did i?

 

[Gun Runner 5]

yep, i am one of "those guys" recommending getting rid of the AC IN A LJ78 or KZJ78 but this is a PZJ70, a real truck.
<sheesh>

David, i like to help.

"PZJ70, a real truck"...... only a U.S. politician could interpret that statement differently.
......1978HJ45

 

[crushers]

"PZJ70, a real truck"...... only a U.S. politician could interpret that statement differently.
......1978HJ45

 

[gatier]

Hey Wayne, can you let somebody else shoot the pictures? They are terrible!
Sorry I couldn't resist

 

[Gun Runner 5]

Hey Wayne, can you let somebody else shoot the pictures? They are terrible!
Sorry I couldn't resist

When you get to be Wayne's age your eyesight is bad enough you don't even realize the photos are blurry so cut him some slack.
......1978HJ45

 

[crushers]

can't make everyone happy so i don't bother trying to make ANYONE happy.
damn camera has seen the mud hole a couple times too many.

 

[Gun Runner 5]

can't make everyone happy so i don't bother trying to make ANYONE happy.
**** camera has seen the mud hole a couple times too many.[/QUOTE

Yep, I would blame it on the camera also.
.......1978HJ45

 

[jzilla]

So I can just pull the pulley off while it is in the truck? I don't have to remove the compressor?
Any trick to getting the pulley off?

 

[roscoFJ73]

So I can just pull the pulley off while it is in the truck? I don't have to remove the compressor?
Any trick to getting the pulley off?

On my 1HZ pump it was possible if you have the proper circlip pliers.