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There's a bird under my hood!

Pruittx2

Been around a bit
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Location
Lake Odessa, Mi
Ok, I know what your thinking,,, and no I didn't drive thru a flock. :hihi:

What I do have is a light chirping sound, that seems to be from my AC compressor. It's not loud, and has people telling me to change my belt.

Belt is new, idler is new, alt and water pump are new. The oldest thing in the equation is compressor. the noise get's worse when I wash the truck at the car wash, and spray water thru the grill.

Everything works, 14+ amps, cold air. great cooling, ect.

So is there a repair I can do with out pulling down the ac, like replace the front clutch pack, that will fix what I believe is a bearing squealing in the compressor?

Let's hear it, fellow guru's, diesel nutz, and been there done that guys. :agreed:
 
Well,,,, Belt, W-Pump, idler, all New by PO @ GM dealership, approx 7-9K miles ago. Don't think it is belt, Burb didn't do this when i first got it. PO Barely put 20,000 miles on it in 10 years. Now I use it daily. It started slowly, and at first I thought it might be from worn fan clutch, as I know I'd be doing duramax fan and HD clutch. I went ahead and did that, but still had noise, that would not be too persistent.

Now I did just put on a CS144 145amp 96 burb Alt on my 95. That did seem to change the noise to the more persistent bird chip sound. So maybe a bit more tightness in the belt. which could make it the belt, or more tension on the ac clutch.
 
Alternator change ??? I had a reman I got from GM dealer once 3 weeks after installing it, chirped like birds swapped it out for a Duralast Gold and chirp went away for a couple of years, lifetime warranty on it so I replaced again been 3 years now chirp free
 
This is a new unit sold by O O O Orieliey's. but the sound is deff coming from compressor area. pry bar to the thumb, held to ear, touching alt, idler, ac, and it is deff coming from pass side. That's why I was questioning the ac bearings, and if those were replaceable with out doing the whole darn compressor.
 
The CS144 change may require a longer belt. Take a pic of the tensioner where the lines are. This will help us see if the belt is too tight and ruining bearings.

Vac pump may be going out. (Or already "out" permanently :hihi: )

The tensioner may be the wrong part number as the newer, AC on driver side, units have a weaker spring than the old ones that had to hold the full compressor load. As the compressor kicks in the belt would squeal with the weaker spring. My experience was with autozone and the newer part...

Have you checked to make sure the pulleys are in line?

Belt clean of does it have an oil or water mist on it from bad radiator or oil leaks?

Spun everything with the belt off? You can feel or hear a bad bearing most times. Run the engine 2 min max with belt of to verify it is the belt drive?

Checked the crank pulley for bad rubber?

Last is excessive load with the AC on due to plugged orface tube or other high head pressure problems. Like restricted condenser behind oil cooler, internally, lack of oil in the system locking up the compressor.
 
Another way to check belt is VERY CAREFULLY rub a candle on back of belt while running. Belt dressing makes a mess but is also easy and can real quickly stop a belt chirp for a little while. Just an easy way to rule out belt chirp. Then you can investigate other areas.
 
I have the exact same issue on mine. I think its my P/S pump though. If I remove the belt then fire it up the noise is gone. Im to the point I just run it, when something breaks I'll know what it was :hihi:
 
The CS144 change may require a longer belt. Take a pic of the tensioner where the lines are. This will help us see if the belt is too tight and ruining bearings.

Vac pump may be going out. (Or already "out" permanently :hihi: ) Yep it's gone


The tensioner may be the wrong part number as the newer, AC on driver side, units have a weaker spring than the old ones that had to hold the full compressor load. As the compressor kicks in the belt would squeal with the weaker spring. My experience was with autozone and the newer part... I'll double check that,, It is a GM tenioner. will check lines.

Have you checked to make sure the pulleys are in line? Yep, seem pretty darn straight

Belt clean of does it have an oil or water mist on it from bad radiator or oil leaks? Clean as a whistle, NO leaks anywhere. Gotta love Anal previous owners :)

Spun everything with the belt off? Nope will in the morning though You can feel or hear a bad bearing most times. Run the engine 2 min max with belt of to verify it is the belt drive? Will do

Checked the crank pulley for bad rubber? Yep all looks good there,,, Posted pic's a few threads back


Last is excessive load with the AC on due to plugged orface tube or other high head pressure problems. Like restricted condenser behind oil cooler, internally, lack of oil in the system locking up the compressor.



I'll be out in garage tomorrow, to finish plow bracket install, putting rear bumper back on,, from the rocker bed liner install from last week end,, and then to track down a, new yesterday, rapid left turn signal, that appears to be bad circuit board in tail lamp assem.

I'll do the test's as mentioned above, and report back.
 
Ok here is a pic, of a few things,, 1 the idler tension lines,, then the CS144 140amp alt I installed last week. The required the bracket on the back of the idler pulley tensioner to be flipped,, then a 1 in spacer fabbed out of a ceiling fan extension tube, then for a new rear bracket a turn buckle used on fencing. bolted to the back, and to the front manifold stud. This after removing the 1995 rear alt bracket all together.

010.jpg


Tensioner lines,,, you think this should get a belt a tad longer????

003.jpg
 
Check and make sure the alt bolts and brackets are tight. I put a new belt on and it made noises a couple days later then i figured out that the alt was loose, its worth a try
 
OK i forgot about this little trick i do at work, when ever a car comes in with a complaint about a belt noise, if the belt is chirping, i take alittle bit of sand paper when the car is running i carefully touch the ribbed side of the belt with the sand paper and lightly touch it with some force, Its best to hold onto it with some needle nose pliers and just lightly push it on the belt and see if the noise goes away. If it goes away the problem is the belt, if it does not go away the problem is one of the pulleys. This works because it makes the belt bite alittle harder and grip the pulleys alot better worth a try if you have some sand paper.
 
The way the lines look,,, your saying that belt is too long? Hell's bell's,, it was a biotch to get that one on!

I'll check the tach versus the GMTD scan readings on the laptop Sunday. I got the plow bracket on today, and the wiring almost done. More Sunday.
 
The single tab on the back of the tensioner should be between the two tabs on the front
 
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