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Old 06-22-2020, 01:37 PM   #1
prodjay10
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Ac compressor or belt?

https://youtu.be/nOFSgiOk7nw

I get a whine when I turn on the AC and it gets worse as I accelerate. At 2100 rpm it overpowers the engine noise. In the video I started truck with AC on, turned it off, then back on.

Aftermarket under dash AC bought on eBay with SD508 style compressor.
No instructions so I added 5oz pag46 and 24oz r134a per sanden instruction on this style of AC. Cools the cabin down fine on a 105* day. It's not freezing us out but I still need to angle the evaporator down a bit, and fill all the holes in the firewall and floor.
Ict high mount ac compressor bracket
New belt 100.5 inches. I can barely slip serpentine belt on.

Is it the compressor or belt/bracket combo? I was trying to see if it was the belt slipping so I sprayed water on the belt and it slipped right off. Tried it again this morning and it stayed on, but I saw it move around on the small smooth pulley.
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Old 06-22-2020, 04:37 PM   #2
dean jendro
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Re: Ac compressor or belt?

I don't hear any noise when the a/c pump isn't running. The noise comes on strong when the pump kicks in. Bad bearings in pump? You stated that the serp belt would barely slip on. Don't you have an idler pulley? A sprung idler would give you enough slack to install the belt, assuming it's long enough.
Your a/c pump pulley looks to have more grooves than the belt. All the pulleys should have the same number of grooves as the belt, be lined up correctly and that will keep your belt on whether it's wet or dry.
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Old 06-22-2020, 05:12 PM   #3
AussieinNC
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Re: Ac compressor or belt?

Did you place the correct amount and type of oil into the system before charging it?

This sounds like a dry system to me....

Please post a pic of the front view of the engine showing thr drive pulleys and idler system....

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Old 06-22-2020, 05:52 PM   #4
prodjay10
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Re: Ac compressor or belt?

5oz pag 46 and 24oz r134a. The amounts are from Sanden's instruction on this style of AC. Poured the oil all in the compressor. The kit didn't come with instructions.

It does have a tensioner. I just went with the shortest belt possible to prevent a squeal.

I could only find 8 groove. It doesn't seem to be the issue since the belt doesn't walk on that pulley and as far as I can tell it's all lined up. But that's just as far as I can tell with no special tools.

I'll get pictures in a bit.
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Old 06-22-2020, 06:31 PM   #5
AussieinNC
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Re: Ac compressor or belt?

Quote:
Originally Posted by prodjay10 View Post
5oz pag 46 and 24oz r134a. The amounts are from Sanden's instruction on this style of AC. Poured the oil all in the compressor. The kit didn't come with instructions.

It does have a tensioner. I just went with the shortest belt possible to prevent a squeal.

I could only find 8 groove. It doesn't seem to be the issue since the belt doesn't walk on that pulley and as far as I can tell it's all lined up. But that's just as far as I can tell with no special tools.

I'll get pictures in a bit.
The groove count on the belt must match the lowest groove count on a pulley in the system...If you have a six groove pulley and are running an 8 groove belt it will squeal....
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Old 06-23-2020, 10:30 AM   #6
kglowacky
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Re: Ac compressor or belt?

My ac man told me if you install the condenser with the small dia line on the top you will get a air hammer noise as you increase speed. He says the bigger dia line on top. Now saying that my 2001 Firebird has the smaller line on top. Maybe after market systems have to run with big line on top. I am just passing this on I really don't have a clue about ac,
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Old 06-27-2020, 04:08 PM   #7
prodjay10
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Re: Ac compressor or belt?

Larger hose is on top. Thats the hose coming from the compressor.

I think it was my fault because a sd508 should have sp-15 oil which is around pag 100 viscosity. I'm thinking of removing as much oil as I can and add sp-15.
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Old 06-27-2020, 04:11 PM   #8
prodjay10
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Re: Ac compressor or belt?

Out of curiosity, this is in a ls swap from a 2002 or so. What does it take to request AC from the pcm to up idle?

Also, should this compressor cycle on and off? The compressor is always on. It's not controlled by the pcm, just by the trinary switch. The only thing I see cycle is the electric fan before the engine reaches temp. After that the fan is always on.
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Old 06-27-2020, 08:56 PM   #9
kglowacky
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Re: Ac compressor or belt?

I am getting ready to fire my ac up and here's some things I have been told. I am running my ac with no help from the pcm. Therefore the pcm only controls the fans (both of them) based on engine temp. So when you say they come on as the engine heats up that is the way they should work. I am going to run a wire to my second fan threw a relay so that when I turn on my ac it will turn on my second fan even if the PCM doesn't turn it on (based on engine temp). Therefor I will always have fan running when ac is on. Next your ac compressor should cycle on and off. from what have been told you do this cycling by adjusting the tirnary switch. There is a small screw on mine between the two wire connections that you can screw in or out . This will set the a pressure range to shut the compressor off when it gets to a set high pressure range you have just set. My ac man says about 32 psi. Please this information is second hand so please do research before e you use anything I say. Keep us posted I will post when I get mine going. good luck
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