Whirling Sound While AC is Turned On, Matches Up With RPM

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JamesSam

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It *** supposed to rain all day here but only for a few hours in the late afternoon. I managed to pop the hood and idle the truck then turnt the AC on and off. Definitely coming from the compressor or the compressor clutch. Now battling my inner thoughts as to when and which compressor to install. Doesn't seem like I will be able to just roll to an auto part store and pick one up around here. Gonna have to order one.

Do I buy new low end, reassembled low end, or go for AC Delco new or reassembled? They all cost a pretty penny.
 
squaredeal91

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I would try to get something good name brand so you Don't have to do this again for a while.
 
JamesSam

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So I decided I was going to get AC Delco or "GM Parts" from Rock Auto. I saw a couple YToob videos on replacing compressors...trying to find one specific to 1987 is not so easy. Anyway, looking through the service manual and catching a few heads ups from install info, it looks like a bit more than just filling the compressor with PAG oil and replacing.

Is it necessary to empty the system of refrigerant, replacing orrifice tubes, receiver drier, o-rings, etc...?

Starting to make me think this could be on another level for me. I was planning to knock this out in a matter of hours or possibly over the course of a few days on and off as work and life will allow. I might need to turn this in to the pros at the garage and eat the labor. I would like to save the money though.
 
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AC work on a square, where everything is accessible, isn't too bad. I'd also replace the orifice tube and accumulator/drier while the system is open. As long as the compressor hasn't failed and sent particles throughout the system, you shouldn't need to flush. But if you do need to flush, you can rent the tool for that if you have a compressor. You can borrow a vacuum and gauges from the auto parts store to pull a vacuum and recharge. Or have a shop pull the vac and recharge after you do everything else.
 
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You should replace the receiver drier ANYTIME the system is open,and of coarse replace the orings. On post 13 I told you find a receiver drier and a compressor before it blows up,just so you can avoid what @gmbellew mentioned above.
Dammmit it says whirling noise,I thought it said whirring noise,this changes everything.
 
squaredeal91

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If anything do the work replacing what you want yourself and have the shop just leak down and refill.
 
TX87R10

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Did you try to take a long screwdriver and check for vibration around the compressor? I found a missing bolt was causing a lot of vibration noise I thought was a bad compressor clutch until my cousin wedged a screwdriver in between the compressor and the different mounts until it stopped. Turned out the M12 bolt on the bottom of the compressor was awol
 
JamesSam

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Seems it may be just in the clutch? Sounds like the rings in the clutch are banging in to each other doesn’t it. @TX87R10 your last info inspired me to look for something obvious. Nothing seems loose like a bolt or bolts are missing. Entire compressor? just the clutch? Maybe this clip will call out to someone that has seen this exactly...
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TX87R10

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JamesSam said:
Seems it may be just in the clutch? Sounds like the rings in the clutch are banging in to each other doesn’t it. @TX87R10 your last info inspired me to look for something obvious. Nothing seems loose like a bolt or bolts are missing. Entire compressor? just the clutch? Maybe this clip will call out to someone that has seen this exactly...
xc_hide_links_from_guests_guests_error_hide_media
Click to expand...
Lol this is gonna sound crazy but are you sure the belt isn't hitting the front bracket? I know that sounds crazy but I swear I see it slapping it and some wear on the bracket
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Probably the clutch or smth like you mentioned but figured I would mention just in case.
 
JamesSam

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TX87R10 said:
Lol this is gonna sound crazy but are you sure the belt isn't hitting the front bracket? I know that sounds crazy but I swear I see it slapping it and some wear on the bracket
You must be registered for see images attach


Probably the clutch or smth like you mentioned but figured I would mention just in case.
Click to expand...
Ok. So possibly I just need to adjust the bracket and get a new serpentine eh? Re- watching my vid....
 
WFO

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JamesSam said:
Ok. So possibly I just need to adjust the bracket and get a new serpentine eh? Re- watching my vid....
Click to expand...
I'd start by just tightening the belt first.
Does the belt show any signs of wear?
And it's called a V-Belt.
 
JamesSam

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It does seem a little bit frayed. I was not even thinking or looking for the belt slapping something. I have just been staring at the compressor and the clutch the whole time. Watching my video back, it definitely is loose more than just running and flops out noticeably when the AC gets turned on. Thanks SB crew. I will get back after tightening the "V belt"...can you tell a guy that doesn't know directly off hand how to do that?
 
TX87R10

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JamesSam said:
It does seem a little bit frayed. I was not even thinking or looking for the belt slapping something. I have just been staring at the compressor and the clutch the whole time. Watching my video back, it definitely is loose more than just running and flops out noticeably when the AC gets turned on. Thanks SB crew. I will get back after tightening the "V belt"...can you tell a guy that doesn't know directly off hand how to do that?
Click to expand...

I use a 1/2" breaker bar in the square hole you see on top, loosen the bolts mounting compressor to brackets, give it a good pull, and tighten them back up.
 
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WFO

WFO

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JamesSam said:
It does seem a little bit frayed. I was not even thinking or looking for the belt slapping something. I have just been staring at the compressor and the clutch the whole time. Watching my video back, it definitely is loose more than just running and flops out noticeably when the AC gets turned on. Thanks SB crew. I will get back after tightening the "V belt"...can you tell a guy that doesn't know directly off hand how to do that?
Click to expand...
Loosen the pivot bolt on the bottom bracket.
Then slightly loosen the bolt that's able to slide in the top bracket.
Tighten the belt a little more than it is, with a prybar or big screwdriver, while retightening the top bolt.
It will stay in place without the prybar now. Then tighten the pivot bolt.
 
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