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DIY A/C Repair Questions

I plan to replace various a/c parts in my 1998 Honda Civic DX.

My a/c compressor broke two years ago. Before it broke, the a/c compressor made high pitched sounds and the pulley locked up. My mechanic told me that the a/c compressor was ruined. I cut the a/c compressor belt and left it alone - until now. I recently had the r134 refrigerant drained. I now plan to replace the a/c compressor, condenser, and the drier. Once those are installed, I will have a professional mechanic add refrigerant and charge it.


1) Should I have anything else replaced? The evaporator? The expansion valve? When should those be replaced?

2) What about the various lines/hoses (discharge lines/hoses, suction lines/hoses, receiver lines/hoses)? Should those be replaced? Should those items be professionally flushed?

3) Does installing a new a/c compressor just involve physically removing the old one and installing the new one?

4) Should I lubricate the o-rings on the new a/c compressor and/or other o-rings; such as the o-rings on the lines/hoses? My a/c compressor comes with refrigerant oil.

5) Is there anything else I should know?

All you need to rebuild an AC system is the compressor, the drier, the expansion valve, an O-ring kit for all the fittings, and some refrigerant oil as far as parts.

The condenser, the evaporator, nor the hoses need to be replaced. But they need to be flushed to remove any debris that the old destroyed compressor may have left in these components. Not doing this can result in this debis coming back and destroying the new compressor, expansion valve, or plugging up the drier.
So this means you’ll have to aquire the proper chemicals and equipment that allows flushing of these components prior to reassembling. Just price out the flushing chemical!

When it comes to repairing AC compressor failure, there’s no short cuts! Do it right! Or don’t do it at all!


You go to a good shop. Explain that you want a flush and recharge. Tell them the New Parts and not to flush them.
Or you do that part. Do you have a really good air compressor? The flush is simple but if you have someone else do it make them know no to flush the new parts, until the old parts are well cleaned. Then you are good to go. I’ve done the job it can be messy if you are not ready and you must have a good air compressor. You will need to cob together a couple of fittings that are easy to do. But you really cannot refill the system without an AC vacuum pump. That is why you need a shop. They need to remove the air before filling the system.
Tester is on the mark.

The big question is if the system is contaminated. Did the compressor have a internal failure, and caused debris in the system? Or did the compressor lock up because the clutch bearing assembly? In the latter case the system may be contaminate free.

You need to determine the level of containment before knowing how to proceed.

Buy the time cold air is blowing out, you will wind up spending more than the car is worth…

I don’t think the value of the car is the greatest measure of whether or not a repair should be done. In addition, i’ve replaced seized compressors (such as the one on my friends '94 Corsica) for a relatively little amount of money. I think all said and done he was out about $250 for parts and having a shop evac and recharge the system. It’s been blowing cold ever since.

I agree. I also like repairing my vehicle (I am the original poster). It helps me learn about the vehicle and its components.

In my case, when I did my '89 Accord it did end up getting a little expensive because after replacing my compressor, receiver/drier and expansion valve and charging the system I discovered that my condenser was leaking, which added on another little expense. Luckily the shop evaced the remaining refrigerant and recharged it after I replaced the condenser for free as they had a leak guarantee (it passed their leak check the first time for holding vacuum).

If you’re not planning on selling the vehicle soon than it makes more sense to consider what the vehicle is worth to you rather than to someone else.