Automotive A/C

[77 R GO C MH]

This won't be a unique question but a tough one for me. I have a '77, 28' Argosy MH in which the auto A/C is not functioning. I took it in to have the refrigerant replaced, which they did, but told me the compressor was bad and needed replaced to the tune of $800. It is not cooling at all. My question: is this a task I could do myself and are there any access tricks to getting at the compressor. I can see it but it is going to be very tough to get at and work on (which is the reason I was told it would cost so much).

[dadstoy]

On my '82 I can remove the dog house and the front metal cover that the dog house hinges to and I have complete access to the compressor

[77 R GO C MH]

I didn't know if the metal cover would come off but I'll look at it and see. Thanks.

[HowieE]

If they told you the compressor was bad AND added freon they are thieves.

They would have know the compressor was bad before they did anything to the AC as the compressor has to be running in order to add the freon.

Yes you can change the compressor as far as the mechanical aspects are concerned but you will lose any charge that in in the AC and will have to have a vacuum pump to evacuate the system before adding any charge.

Sorry for the harshness of my opening comment but I live in New Jersey where all mechanics are thieves

[ROBERT CROSS]

Originally Posted by HowieE

If they told you the compressor was bad AND added freon they are thieves.

Howie,

I resemble that remark, we don't know that for sure. Not even in NJ.

Did they charge the system, tell you that the compressor is bad and then evacuate the system before returning your vehicle. If you declined the repair that would be the proper procedure. It is against regulations to let a known leak leave the repair shop. They could test the system by adding a dye tracer and require another appointment to re-test.

Was the compressor operating but noisy, was there evidence of a leak?

[77 R GO C MH]

Thanks again. I was informed that after they charged the A/C the compressor was "weak". They told me that it was not leaking, and I had no evidence for this, and that it only needed 1 pound of freon but may not cool because the compressor was bad. I have suspected this for a while.

[ROBERT CROSS]

Originally Posted by 77 R GO C MH

Thanks again. I was informed that after they charged the A/C the compressor was "weak". They told me that it was not leaking, and I had no evidence for this, and that it only needed 1 pound of freon but may not cool because the compressor was bad. I have suspected this for a while.

Just one more suggestion....a second opinion.
If it was "WEAK" that would show up in the pressures. A good shop would be willing to show you that during the diagnosis.

POI...one pound of refrigerant would significantly reduce cooling, do not rule out a leak, possible evaporator which can be hard to diagnose, AND repair, very time consuming as opposed to a relatively quick R&R.

BTW...has the system been converted to the 134 refrigerant.

[77 R GO C MH]

Thanks Robert. Helpful suggestions.
Yes, I was told it was converted to the R136.

[HowieE]

If it was converted to 134A even a good compressor will only be 90% as effective as a system filled with 12. Just the nature of the beast.

There is no way they could have just added 1 lb. of 134A to the system without evacuating the 12. first and refilling the complete system. The 2 gases done mix.

An easy way the check for a bad valve, common symptom of a weak compressor, is to touch the LARGE pipe at the compressor. If the system is charged that should be cold to the touch. If you feel heat as you touch closer to the compressor there is most likely a bad valve in the compressor leaking bad into the suction pipe. This will show as a higher suction pressure if a guage is put on the port. A true test requires that a gauge be placed on both the high and low sides and comparing the presssures against a cyclomatic chart.

be careful who you let play with it because a lot of the recharges that have leak detection in them will render the system not serviceable with most recharge system as those leak detection chemicals contaminate the vacuum pumps used during recovery.