Leak troubleshooting

Solar4 on Wed August 19, 2015 1:13 AM

Year: 2000
Make: Honda
Model: Accord
Engine Size: 2.3
Refrigerant Type: 134a
Ambient Temp: 92
Pressure Low: 10
Pressure High: 110
Country of Origin: United States

Car cooled fine two days ago. Start driving, turn on AC and hear a hissing sound from evaporator/ TXV area. No cool air from vents. Later check static pressure at 66PSI. Crank up, turn on AC, compressor engages and get the high & low readings above. So I'm thinking low charge caused by a leak. Is the hissing sound normal when running with such a low charge?

I tried uploading a pic of the compressor. It had a decent amount of dirt buildup on 3 vertical lines of the compressor body. The heaviest buildup on the left side, just below the high & low side fitting (I scraped away some on the left side)

Should I somehow locate or aquire a sniffer? Or add some freon that has some leak detector? Or, am I wasting my time cause it's definitely the compressor leaking. I couldn't find any other 'wet/ dirty' areas other than on the compressor. Any troubleshooting suggestions for someone that doesn't own a leak detector?

compressor

Cussboy on Wed August 19, 2015 9:26 AM

Disclaimer: I'm not a certified AC mechanic. I'm semi-knowledgeable and have done about a dozen compressors, and a couple of evaporators, AC electrics, etc.

Yes, you have a leak, evident from your pressure readings and lack of cooling performance. I looked at your photo, and the connections to the compressor look good. It does look to me like your compressor is leaking at the seams between the sections. So compressor is bad, don't use it.

I wouldn't buy a sniffer right now. If you feel you need to confirm the compressor leakage, try some soap bubble solution to confirm the leak.

Others may disagree, but in this instance since you caught the issue before compressor made terrible noises or seized, and still has refrigerant pressure so no air is getting in (yet), you may be able to get away with simply replacing the compressor and not doing the drier, condenser, etc. I did similar 2.5 weeks ago on our 2005 Yukon, and just replaced the compressor.

Edited: Wed August 19, 2015 at 9:29 AM by Cussboy

mk378 on Wed August 19, 2015 10:03 AM

Take one of the service caps off and see if the oil in there is dyed (yellow-green). If you already have dye you can look for leaks with a "blacklight" CFL bulb. Wait for darkness or park in a garage with the lights out for best visibility.

It does look like trouble on the back end of the compressor though. If you open the system I would put a new drier since yours is 15 years old, they're an expendable part like an oil filter. Also if it doesn't already have dye you should put some in to make finding leaks easier in the future.

Edited: Wed August 19, 2015 at 10:05 AM by mk378

Solar4 on Wed August 19, 2015 1:50 PM

Update. Wanted to add that the compressor, condensor & dryer were replaced 3.5 years/ 20K miles ago. It has been working great until now. Don't remember if it was a rebuilt or new compressor (probably from Autozone or Oreilly's). MK378, after removing the gauges I did notice a little bit of green color in the port. Will look for a blacklight to try.

If it is indeed the compressor, any advice for the SECOND replacement? Remanufactured & new from O'Reillys run $170 & $220. Remanufactured & new from Honda (Denso) are $475 & $645. Should I spend the extra on either the remanucatured or new Densos from Honda versus the junk that put me in this position 3.5 years later? Perhaps a fluke, or maybe you get what you pay for? Car has 187K miles on it. Plan on keeping a while as long as it keeps running and keeps me from sweating during the Texas summers!

bohica2xo on Wed August 19, 2015 2:15 PM

Everything leaks. It is all about the rate. 50 molecules a week? Undetectable. An ounce a week? Yeah, fix that one.

Your cooling stopped when it slipped below the Critical Charge. If you can't find a big leak from a recent failure, you can charge it to see what the loss rate is. It may have been leaking slowly for 3 years.

.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

Cussboy on Wed August 19, 2015 2:21 PM

I'd go with NEW compressor. Check AMA board sponsor. ackits.com

Solar4 on Tue September 01, 2015 3:14 PM

Appreciate the responses. After further inspection, the underside of the compressor was damp with oil and left a nice dirt trail on the frame areas below it. Replaced the compressor, dryer and TXV. Cooling great for 9+ days now.

Also, I bet most of you are aware but just in case someone else (like me) reads this down the road; DO NOT use the o-rings that come with the dryer! They looked like the right size but caused the vacuum to lose 10" over about 30 minutes. Extra time spent on leak troubleshooting and lesson learned!