AC Compressor bearing fail..do I really need to replace..? (1 Viewer)

[nigelsiam]

Recently my AC compressor bearing failed and I thought I would be able to just replace the bearing but the whole bearing/clutch wiring was all f'd. So I am going to put a new compressor in it. Many suggest to replace the receiver/dryer ( I have no problem with that) but also to replace the expansion valve (lot more work) but there was nothing wrong with the system except for the compressor bearing.
Can I get by just replacing the compressor and receiver/dryer?

thanks!

 

[baldilocks]

It sounds like you could get away with replacing only the compressor.

New compressors come with oil in them but usually not enough. You might dump all the oil from the new pump and then service it with PAG46. I don’t remember the exact Number of milliliters to add bit 80ml comes to mind.

 

[nigelsiam]

It sounds like you could get away with replacing only the compressor.

New compressors come with oil in them but usually not enough. You might dump all the oil from the new pump and then service it with PAG46. I don’t remember the exact Number of milliliters to add bit 80ml comes to mind.

Cool...thanks. I was thinking to replace it and bring it somewhere to have them refill with oil and R134

 

[baldilocks]

Sounds like a solid plan. But, if you feel froggy, the drier unit is cheap and easy to replace. If you do replace it, remember to add even more oil because most oil in the system is in the pump and dryer.

 

[maxamillion2345]

I'd replace drier for sure. Theyre cheap and easy.

 

[nigelsiam]

Yeah for sure I'll replace the drier. Maybe even lift it up for more clearance while I'm at it.
Thanks for all the help

 

[slow95z]

the expansion valve really isnt that bad to do, maybe 2 hours or so. when i did mine i found the core was FULL of leaves and dirt. cooled so much better after i cleaned it all out.

 

[Michael Hanson]

Hi, Def. clean the core. Mike

 

[secretasiansam]

Expansion valve isn't hard to change, and is known to fail. If it goes youll have to replace the dryer again when you replace the expansion valve.

 

[-Spike-]

Careful adding oil. The compressors don't come with the entire amount of oil required for the system because if it's a used system there's already oil in the lines, condenser, evaporator, etc. Normally the oil that comes in the new compressor is plenty.

 

[flintknapper]

Careful adding oil. The compressors don't come with the entire amount of oil required for the system because if it's a used system there's already oil in the lines, condenser, evaporator, etc. Normally the oil that comes in the new compressor is plenty.

^^^^^ Correct. The system (if not a retrofit) is designed for 8 oz. (PAG46) TOTAL.

When replacing a compressor ONLY and there was no appreciable leakage prior the replacement, then drain the oil from the old compressor, note how much it was and put the same amount of new PAG46 in the new compressor (after having first drained it).

Too much oil in the system will affect the cooling capability. Too little will result in premature compressor failure.

 

[Marine7]

Most manufacturers won’t warranty a compressor unless a NEW drier was installed at the same time. For the small amount of $$$, I’d just change it. Good luck!

 

[BILT4ME]

Are you converting an R12 truck to R134? If so, then you MUST replace the drier, expansion valve, the fittings, and the oil in the compressor.

R12 oil and R134 oil do not get along and will clog the system.

If you're doing it, may as well do it right. Clean out the evaporator and do the expansion valve.

 

[maxamillion2345]

Toyota r12 to r134a TSB says to add pag oil to system and let mineral oil hang out...

I mean not that I would do that personally but just saying...


In fact I'd flush evap, replace txv and drier and at least flush the condenser. It is only 150$ if you're feeling froggy though... and the evap is only 100$ both Denso parts.

None of its difficult to do. Hardest part is getting evap and condenser flushed, need a LOT of air. I kept getting crap out of the evap for ever and ever. Almost easier to just replace.

 

[flintknapper]

^^^^ Guys...no one has said he is 'converting'. I only mentioned it because the OP didn't say.... and IF that were the case, the amount (and type) of oil would be different.

 

[maxamillion2345]

All the same I'd replace txv, clean evap externally, and replace drier personally.

 

[nigelsiam]

Yeah I am not converting it as it already is a r134a system. But for sure replacing the drier/receiver. I wonder if I brought it someplace to evacuate the system is it like starting over with a clean system? So they put the right amount of r134a AND the 8oz of oil? I will ask because I won't be filling it myself.
Thanks everyone

 

[-Spike-]

No, evacuation will only remove the gasses (and any air that has gotten in) along with most of any moisture (if they leave it on long enough). The oil stays. That's one of the reasons it's best not to ever crack open the system if it's not needed. Unless you replace literally everything, you will never know how much oil is in the system for sure. Flintknapper's method above is about as close as you can get, but some stuff will also be lost in the dryer. I doubt if you'll get a shop to do that. I believe the amount of oil shipped in a new compressor is intended to replace what they assume you'll lose when you change the compressor out, and it's probably close enough.

 

[flintknapper]

I wonder if I brought it someplace to evacuate the system is it like starting over with a clean system? So they put the right amount of r134a AND the 8oz of oil? I will ask because I won't be filling it myself.

You have two choices:

1. Replace compressor and drier (and I would recommend the TXV and inspect and clean evaporator while its out). Add a small amount of oil to drier FSM specifies amount. Add same amount of oil to new compressor as came out of the old one.

2. Have the system flushed and start anew with a known amount of oil (and clear, clean lines and components).


If you choose option #1 the shop will be 'guessing' at the amount of oil to add. They have no way of knowing how much oil is in the system now. IF the system has ever been serviced before....it is not unusual for techs to add oil to it (even if only adding refrigerant). A small 'overage' isn't going to cause you any trouble...but you get several ounces over (oil) and you will have diminished cooling capacity.

Note: 'Most' compressor manufacturers will not honor the warranty unless the system has been flushed AND a new drier installed. So read your warranty information. Additionally, some require that a qualified tech do the work.

 

[GeoRoss]

Careful adding oil. The compressors don't come with the entire amount of oil required for the system because if it's a used system there's already oil in the lines, condenser, evaporator, etc. Normally the oil that comes in the new compressor is plenty.

^^^^^ Correct. The system (if not a retrofit) is designed for 8 oz. (PAG46) TOTAL.

When replacing a compressor ONLY and there was no appreciable leakage prior the replacement, then drain the oil from the old compressor, note how much it was and put the same amount of new PAG46 in the new compressor (after having first drained it).

Too much oil in the system will affect the cooling capability. Too little will result in premature compressor failure.

I did a pretty big AC service last summer, thanks flintknapper.

New compressor, condenser, expansion valve, drier, schrader valves and all new gaskets. I flushed the system completely, cleaned the evaporator and blower. They were a mess. I drained the oil out of the new compressor to confirm how much. I didn't quite get 8 oz out, but I didn't expect to. I put most back into the compressor, added a little to the condenser and evaporator. I added just a tiny bit of extra oil, I can't recall how much but just enough to almost get it to the full 8 oz. My reasoning was that it would be impossible to completely drain the compressor of oil. Then with some real time questions answered, I got the AC blowing mid 50's while 107˚ outside at idle.