A/C compressor on 93 mx6

[malimx6]

I dont know if this is the right place to ask, but in the last couple of days i tried fixing my a/c system. It died in summer 2002 and just recently i wanted to fix it. The problem was the safety valve. I changed the safety valve, i went to the mechanic and he pressure tested the system. Everything was fine. Then he evacuted the system, and then filled the system with r134a. I turned my a/c on when we were fillin' it up, and it was making a verryyy loud ticking noise. He filled up the system, and the a/c works fine. The pressures were good, and it blows cold air. The problem is, when at idle speed, the compressor most of the time (note: not ALWAYS, but i'd say about 95% of the time) makes that loud ticking noise. When i rev it up a little, or when i start driving, the noise goes away.
When it drops to idle speed (at around 750rpm) the noise shows up again.

Another thing (i did this before i filled up the system and everything) at first i was going to change the compressor. Now, i live in Canada, and those things here are very expensive. I went to junk yard and picked up used compressor. Came home and started taking the compressor off. Took mine off, and then i remembered to spin the thing and see if it was making the noises, before i bought it. So i did it, and it was really bad, made noises and it was a little lose. That's when i figured that my compressor was better than the one i bought. So i returned the compressor and put mine back on the car (it didn't make any noises and it wasn't lose or anything), than i changed the valve and went to fill it up.

Sorry for a long post, but i've been trying to fix it for couple of days, and finally when i did fill it up, it started making that noise.
What is the problem with the compressor? anybody know??
i hope someone here knows the answer to my question, because i tried different forums and no luck

Please help!

Thanks!

 

[Chris142]

So it's making a noise off the car when you spin it by hand?

My only guess is that it's cycling on and off at low speeds due to not enough air going through the condensor or a bad pressure switch.
Or the reed valves in it are worn and doing strange things. But you wouldn't have normal pressures.
When your mechanic retrofitted it to R-134A did he use Ester oil or Pag? He did use an oil other than Mineral oil?

 

[malimx6]

no, MY compressor didn't make noise when i turn it by hand, it was the compressor that i got from junk yard, so that's the reason i returned it.

you see, in canada only certified mechanics can work on a/c system. What i did is, went to states and bought the r134a kit (it includes 3 15oz of refrigirant (12oz of r134 and 3oz of oil)). Since i have to evacute the system FIRST, and i went to that mechanic to do it for me, he said that, once he disconects the hoses, it'll lose some pressure...so he talked me into having HIM evacuate the system and filling it up. So i let him do it, but i dont know if he put any oil in it, because he has the machine to do it, and the machine evacutes the system, then it fills it up.
(i ended up not using the kit that i bought)

someone else told that it might be the valves in a compressor.

i'll go and ask him if he put the oil in!

Thanks!

[ May 19, 2004, 11:55 PM: Message edited by: malimx6 ]