Hello, official first post here,
there's NO a/c bypass pulley for 1991 Vandura 5.7 350 v8 van and I'm going nuts. I bought the van 8 months ago and it was running flawless. Started squealing and noticed it was the a/c compressor. Since I DO NOT WANT/NEED a/c I removed the compressor, but there is no a/c bypass pulley available for my van in planet Earth. Nobody makes it so I guess I will have to ghetto fabricate it, meaning my van will be useless for months/years because I don't have time for it. Anyone out there with the solution please let me know, I love my van and have lots of plans for it. -Leo

 

Pick up a used compressor, and mount it but don't connect the wires. If the clutch does not engage then the compressor won't turn and seize up with no freon/lube inside.....
That would be way easier.....the pulley on the comp will just freewheel.
Or you could check an auto wrecker for the same van without ac.....

 

If you don't have the time to make a bracket for a bypass pulley then pay someone to do it. It isn't that hard and won't take that long. This is better than letting the van sit for months.

 

Ok I installed the old compressor back and did not connect any wires or lines like you said, letting it freewheel. Now it's not squealing but it's chirping, an intermittent chirping noise that goes up or down depending on the RPM. I drove it for about 4 miles and the chirping noise was less, arrived home and was almost gone, very low but I could hear it. Could it be compressor bearing? Or any other bearing? The belt seems properly tight, it has never come loose.

Sorry for my English, it's my second language.

 

Your English is better than most people whom use it as their only language.


I have dripped some oil on noisy pulley/bearings before and it has worked. Just don't get any on the belt.

 

Thanks bro. Will drip some oil on all the pulleys.

I have done some research here and found these reasons for the chirping noise.

1.Worn belt (but mine is almost new)
2.a/c compressor clutch (but mine is disconnected, wires and lines)
3.Out of place or loose pulley (will check)
4.Water pump (but is not all the time)
5.Worn universal joint on drive shaft (but noise is not under the van)
6.Evil dwarf with a whistle

Again, noise goes with RPM, sometimes goes away when van is warm.
Thread name should be change to "91 Vandura chirping noise, where's coming from?"

 

I bet its the alternator. You could remove the belt, and start it up. That will eliminate a few things, also try to spin a few things by hand and see if you hear anything. Also, those metal stethescope things are good for finding that sort of thing.

 

CONFIRMED to be the ac compressor pulley/clutch/bearing! Did like greenfire said and dripped pneumatic tool oil on the ac pulley/bearing, no more chirping, will have to do this forever since there's no bypass pulley available. Thanks people, I will now fabricate one like oldchevy recommended and will post pictures.

 

I have a 95 Vandura and picked up a bypass pulley from AutoZone for about $45. Dorman part# 34207

 

You do know this post is six years old, right?