Q45 Tech: AC Pre-emptive Maintenance
Q45 Tech: AC Pre-emptive Maintenance
94' G50 100K. For most of the cars that I have owned, I normally change out the AC compressor and dryer before 125K, prior to the time they self destruct. The goal of course is to avoid having aluminum filings sprayed through the system and having to change out lots of parts in the system and doing a thorough flush. This normally results in a $600 vs. a $1200+ cost. Would you recommend this strategy for the Q. At what milage/age? Any other suggestions? Currently AC works great. In fact, living in AZ, this is one of the outstanding systems of the car.
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Q45tech
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- Posts: 14296
- Joined: Tue Apr 30, 2002 3:19 am
- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Re: Q45 Tech: AC Pre-emptive Maintenance (sdkhalsa)
My Q compressor lasted until 220,000 miles [summer 2001] however it had been noisey for 20,000 and I should have changed earlier!
I changed the compressor, flexhoses, dryer, and condenser but didn't like a fool flush the evaporator [where stuff was hiding]............it worked well for a year or two then down hill..........then black stuff migrated thru the system to condenser and dryer progressively reducing performance.
Finally I flushed condenser and changed dryer and oil again..[didn't pull evaporator yet]........back to near [My guess is 90%*] brand new performance with a 307,000 mile evaporator.
*My low pressure is not 27-33 psi as designed but I can achieve [47F outlet with a 77F inlet recurculate fan max]. roughly a 37-40 psi low side.
Since the compressor failure [and oil degradtion] is what destroys ac sytems always good to change before it fails but don't forget the TOTAL SYSTEM DISASSEMBLY AND FLUSH and dryer replacement.
As to YOUR 100k TWELVE YEAR OLD COMPRESSOR STRESSED IN ARIZONA........this fall might be a good time..........vacuum down, examine the recovered oil for color/smell.
I changed the compressor, flexhoses, dryer, and condenser but didn't like a fool flush the evaporator [where stuff was hiding]............it worked well for a year or two then down hill..........then black stuff migrated thru the system to condenser and dryer progressively reducing performance.
Finally I flushed condenser and changed dryer and oil again..[didn't pull evaporator yet]........back to near [My guess is 90%*] brand new performance with a 307,000 mile evaporator.
*My low pressure is not 27-33 psi as designed but I can achieve [47F outlet with a 77F inlet recurculate fan max]. roughly a 37-40 psi low side.
Since the compressor failure [and oil degradtion] is what destroys ac sytems always good to change before it fails but don't forget the TOTAL SYSTEM DISASSEMBLY AND FLUSH and dryer replacement.
As to YOUR 100k TWELVE YEAR OLD COMPRESSOR STRESSED IN ARIZONA........this fall might be a good time..........vacuum down, examine the recovered oil for color/smell.
Re: Q45 Tech: AC Pre-emptive Maintenance (Q45tech)
Thanks for your thoughtful answer. Actually the car lived in Ohio for nine of the last 12 years. My thought, based on your approach, is to have the entire system flushed and recharged sometime before the next Spring/Summer, changing the dryer and inspecting the hoses. Projecting a lifetime for the vehicle of maybe two years, it sounds like there is a good chance of lasting the duration with some light maintenance on the AC.