AC compressor squeal

[rickster991]

I have a BP 347 with AC. I just started using AC. It squeaks when I turn on the AC and then continues to make noises sporadically when it’s on. Is the belt loose? I had it professionally charged and they assured me they added oil when they filled it. The belt seems plenty tight. Any advice is appreciated.

[bobl]

Replace the belt with a "gatorback" belt.

[CraigS]

Try putting some of this on the belt grooved side any place you can get your finger to. Engine off of course.
https://shop.advanceautoparts.com/p/american-grease-stick-co.-sil-glyde-silicone-brake-lubricant-tube-4-oz.-bk-4/12024852-P?searchTerm=silglyde

[Railroad]

The a/c people probably overcharged your system. I never had to add compressor oil on a recharge.
good luck,

[rich grsc]

I don't think you had a professional do the work, not if they added oil.

[J R Jones]

Charging is unlikely to result in any change of noise. The oil is to lubricate the compressor internally and that will not create noise.
There are two potential parts that can make noise, the belt and the clutch. The clutch is a magnetic "clamp" that causes the compressor to engage and disengage. The clutch thrust adjustment is fine and not easy to do. It requires a special tool to pull or push the clutch on the shaft.
If you experience the noise and spray the belt (inside) with a light belt dressing or silicone and the noise goes away, that is the source. Do you have an idler pulley or tensioner on the AC drive?
jim

[rickster991]

It was a pro shop and it was the initial charge. You need to add oil according to the instructions.

223389

I will tighten the belt and see if the noise goes away if not I’ll try dressing spray. Thanks for the advice!

[rickster991]

Thanks Jim! I tightened the belt little by little until the noise went away. So it was an easy fix.

[rich grsc]

Unusual as most compressors come with oil in them. Sorry for the mistaken comment

[rickster991]

No worries…