What have you done to your square lately??

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Powerhouse Ranch

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Can anyone tell me what the hell this thing is and what it does: it's a wheel on the front of the AC Compressor on the other side of the belt. SOMETIMES and i don't know why it does this, but i need to know haha about every 5 seconds this wheel spins for a second and it feels like it pulsates the whole truck as it's running, and it just comes to a complete stop. spins, stops. what is this doing? (this isn't a picture of my engine bay, it's an example online) My truck is a '80 High Sierra 454 with factory A/C that doesn't work at the moment

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Poppy 87

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Can anyone tell me what the hell this thing is and what it does: it's a wheel on the front of the AC Compressor on the other side of the belt. SOMETIMES and i don't know why it does this, but i need to know haha about every 5 seconds this wheel spins for a second and it feels like it pulsates the whole truck as it's running, and it just comes to a complete stop. spins, stops. what is this doing? (this isn't a picture of my engine bay, it's an example online) My truck is a '80 High Sierra 454 with factory A/C that doesn't work at the moment

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That is the a/c compressor clutch that cycles on demand
 

TotalyHucked

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what do you mean "on demand"? what EXACTLY is it doing?
That’s what engages the compressor. When your a/c is off, it allows the pulley to freewheel so there’s not unnecessary wear on the compressor. The clutch engages (just like a clutch in the trans) the compressor when the a/c kicks on. If it’s doing it every 5 seconds, your system is likely low or out of Freon and needs to be serviced. It should engage and stay on for a while before kicking back off. This is usually controlled by a combination of a temp sensor inside the cab and a high pressure switch (though I’ve not worked on squarebody ac systems, only 90s Mustangs so I could be wrong on the control details) to tell the compressor when to engage/disengage


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Powerhouse Ranch

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That’s what engages the compressor. When your a/c is off, it allows the pulley to freewheel so there’s not unnecessary wear on the compressor. The clutch engages (just like a clutch in the trans) the compressor when the a/c kicks on. If it’s doing it every 5 seconds, your system is likely low or out of Freon and needs to be serviced. It should engage and stay on for a while before kicking back off. This is usually controlled by a combination of a temp sensor inside the cab and a high pressure switch (though I’ve not worked on squarebody ac systems, only 90s Mustangs so I could be wrong on the control details) to tell the compressor when to engage/disengage


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even though i know that my AC doesn't work (needs charged/converted) i never use it/turn it on. in fact i had heater/ac off the whole way and it was doing this. should it have been?
 

Backfoot100

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It'll also start cycling if you have the defroster on. If everything is turned off it should nor be running at all.
 

Powerhouse Ranch

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well it doesn't always happen actually. like yes, i do use the heater/defroster. The first time i heard the clutch was last spring after a long drive, then i never heard it again, YET i've been using the heater/defroster alot. Now after starting it up a few times during its winter hibernation and doing some minor power steering work, whenever i start it (with the heater on) it's making this noise again. Like i said, i use the heater/defroster alot, and the clutch rarely makes this noise/engages. . . ?
 
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82sbshortbed

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Added a quart of oil after a trip to Napa to get a oil filter for the 15 camaro. I just love this funnel I got from Walmart. It fits perfectly in the pcv valve hole and comes with an adjustable filler hose like thing. Lol

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82sbshortbed

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Oh and Napa has mobile 1 quarts of oil for 5.99!

At least mine does.
 

82sbshortbed

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Brake pedal was real easy to push till about half way then brakes would work. Brake light came on. So I pulled the top off the Mc to add a little fluid. And the rubber gasket with the round deals that come down as the fluid level does was all contorted and not sealing properly. So I fixed that putting it back right and added some fluid.

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Took it for a spin and the brakes work better now but, the brake light is on. Why?

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DoubleDingo

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Brake pedal was real easy to push till about half way then brakes would work. Brake light came on. So I pulled the top off the Mc to add a little fluid. And the rubber gasket with the round deals that come down as the fluid level does was all contorted and not sealing properly. So I fixed that putting it back right and added some fluid.

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Took it for a spin and the brakes work better now but, the brake light is on. Why?

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May just need a little more time. I've had that happen, and it went out after a couple short drives around the neighborhood.
 

Camar068

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Oh and Napa has mobile 1 quarts of oil for 5.99!

At least mine does.

I've been using amazon basics oil for about $27 for 6 qts. Forget the website, but you can compare different oils to each other (science side of it) and amazon oil was almost as good as Amsoil. Better than other standard brands and cheaper. Makes me not feel bad when I put a wix filter on it :)

[edit] should have mentioned I use 5w30 full synth on the LM7 5.3.

https://pqia.org/passenger-car-motor-oil/
 
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