My AC stopped working some time ago and I am now in the process of diagnosing what is wrong with it. I had a thread on Reddit and I am pretty sure the compressor is bad. So some information, the compressor engages and stays engaged, it has freon (doesn't seem to be losing any) and both fans are operating (radiator/AC.) When I have the AC gauges hooked up I have ~ 60 psi on the low and high sides with the engine off. With the engine on and the compressor engaged the readings stay the same. When I rev the engine the low side goes down by about 5-10 psi and the high side goes up by about the same amount but that's all I get. I am not getting cool air from the vents obviously. I am fairly certain that the compressor is bad. I checked the discharge line coming out of the compressor by hand and with a thermal camera and it is not heating up, it stays about the ambient temperature. I assume that the compressor is leaking internally and not compressing the freon. Aside from the compressor should I replace the dryer and condenser? Also, should I need to flush the AC system?

Thanks for any help!

 

Yes automatically assume both dryer and expansion valve are bad and replace them. It's a PITA to do it, especially the expansion valve, because you have to remove the airbox and battery to create enough slack in the hard lines. The 4mm Allen bolt holding the lines to the valve can break as well.

Get a brand new compressor, don't waste your time with a remanned one. A brand new compressor should be around $450, the one that comes from Honda is twice the price.

I'm really annoyed that shipping is now more expensive and slower to boot. I too will be changing my compressor soon.

When you remove the drier/receiver, you'll know if you need to flush the lines. Look for metal powder at the line entering the drier. Don't mess with the high pressure line going to the condenser, or that bolt may break as well, then you'll need a new condenser.

Backflush from the high line that goes to the drier towards the compressor. Assuming of course the high line is disconnected from the compressor. If you have a leak in the high line coming off the compressor you will have to replace the hose and should prepare yourself in case you need a new condenser as well.

The evaporator doesn't usually end up with metal, the powdered compressor guts usually just wind up clogging the expansion valve.

 

Thank you so much for the advice, I really appreciate it!

 

60 psi with the system equalized (off for a while) is low, unless ambient is fairly cool, 50's-maybe 60 degrees max. With barely any suction and low high side pressure, the expansion valve could be stuck open, but.. read below.

First would be to have the system discharged (recovered) to see what's in it, If significantly low, you have a leak somewhere. The system then vacuumed down, (to boil out any moisture) then charged to proper fill, and dye added.

Running the system with a known full charge, and you see no to little change in either pressure, I'd check the expansion valve first. These systems will NOT cycle off unless evaporator temp nears 34 degrees.

 

where would one get a compressor for $450? I suppose it's a Keihin one since they make them for Honda.

 

A bunch of places online, Kehin is the OEM manufacturer.

 

out of curiosity, you know that it has freon inside? it could have a leak and show pressure. When you connect the gauges some will leak out and it should smell like freon.

 

If the compressor is running and high side pressure is the same as low side its safe to assume the compressor ain't compressin'.