1978 c3 vette l350

So I replaced my refurbished piece of junk a/c compressor since I bought the vette it was sitting awhile and the seal went bad. it was spraying lubricant slowly but everywhere. It was already retro fit. I went to napa and bought a new not refurb compressor orifice tube and drier. When I gave it to the mechanic we noticed the drier that was supposed to be compatible was too large. We pulled out the smaller one it had and I found it at 4 seasons. Off I went back to him and he installed. After filling everything up the bearings start rattling when you turn it on (cools great). I notice the clutch moves (slips) with the a/c off. Out it went back to napa for a new one. New one does the same. Obviously we're doing something wrong. the bearing sound bad when we turn it on. All my belts are wobbling but that's another thread about the crankshaft. This was the case with the old compressor but it never made this noise. There is no tensioner pulley between the a/c and the crankshaft at all as an fyi. Anyway I read elsewhere it has to do with the way in which freon is pumped in. So we did it in 4 parts and it still does it. Any thoughts? I hate to go back to napa to exchange for the 3rd time. 1978 c3 vette l350

 

Tighten belt

 

but why would the compressor make noise when engaged and the clutch try to move when not on? belt is as tight as i can make it

 

I have same napa compressor but r12.. had to adjust the accumulator pipes..and thanks to good advice on here thought the same as you..belt slaps the deflector and make bell bearing noises...tighten it up with good belt...
clutch maybe slapping enough to move it slightly

 

Also pictures help..and adjustment left on belt tightening?
pressures ok?

 

will take pics and video tomorrow after this storm passes.

 

since my balancer is wobbling making the belts wobble as well, i'm going to focus on the balancer first. once it's perfect then i'll tighten belt and see what we get. i really hope it's that. thanks for the heads up.

 

wow I can’t believe i couldn’t hear the incredibly loose belt doing this before. And here I am thinking it’s the compressor. It may still be an issue but the belt slap is the noise I hear. Lol I’m glad I started all this ruckus on here so I can realize my mistake.

 

Ya well. I made same mistake....
very pleased it helped you..

fyi mine has a protective plate..you do not..so the belt dont slap your hose! And break it

 

does it have a shield to prevent leaking oil from being slung up & onto hood? to prevent oil from soaking into fiberglass hood.

 

i have never seen that.. not sure what year OP is.. but i have deflectors at alternator and AC belt..like in this pic of OP area.. no clue if his had originally..

 

i'm on another thread learning to rebuild everything lol. now that i'm 99% done i am going to find that and order it. my hose is uncomfortably close to my belt. thanks agian!

 

old thread but wanted to let ya'll know. i replaced the alternator with a tuff brand. lasted about a month before the capacitors popped open. returned it and got a proform. to get that thing in was a mission. the belt was MUCH tighter after doing that. now all my rattles and a/c compressor ball bearing noise is gone. go figure.

 

I had that issue... it wore a small hole in my lower rad belt rather quickly. One of the reasons I just went with stainless hoses.
as far as my alternator(S)... I rebuilt my original which lasted a few years then started acting up, bought a higher output replacement which was defective also because it would drain the battery overnight., rebuilt that with quality replacement parts and so far so good.