air conditioning not cold RESOLVED, over pressure

jda2000 · Post by **jda2000** » 04 Jul 2011, 14:32

read the post from frans_70 and replace the evaporator temp sensor

Post by **vtl** » 01 Jul 2013, 20:32

Reanimating ancient thread, sorry.

V70 2002, no service records. A/C cools air a little bit, but at 95F it's uncomfortable inside. Compressor works as it should: after engine start it engages for prolonged period, than goes on and off back and forth. I bought a couple of R134a A/C cans (22 oz in total) with coupler and manometer, checked the low side pressure, was going down to ~15 PSI on engine idling and outside temperature 75F. Poured both cans, pressure was fixed at ~37 PSI, and puddle appeared immediately under the car.

In next week overpressure valve worked 3 times. After engine start A/C cools air still better than it was, but in 15 minutes compressor stops engaging and vents blow warm air. Few minutes later compressor starts to engage again, but the pattern changes: engages for several seconds and relax for way longer interval than previously. Air gets bit cooler, its temperature and flow seem to remain steady. I checked evaporator temperature sensor with DiCE/VIDA, with 80F outside and with recirculation enabled it shows 43F. But I can't really feel these 43, not even 50 or 60.

CCM has ambient temp sensor, it shows.... -40F. I checked ambient temp sensors in ECM and PDM, they show correct 80F. CCM does not have any DTC stored. Evaporator drainage is clean.

Ideas?

Post by **vtl** » 02 Jul 2013, 20:12

Nevermind, measured compressor clutch gap is 0.026 or more. Will be doing bread clip fix at weekend.

Post by **abscate** » 03 Jul 2013, 20:16

Classic compressor gap problem behaviour. 22oz of R134A is about 85% of the total charge of the system, so you might have a leak in one of the components

Post by **vtl** » 03 Jul 2013, 20:23

abscate wrote:Classic compressor gap problem behaviour. 22oz of R134A is about 85% of the total charge of the system, so you might have a leak in one of the components

Leak - yes. One of cans had UV dye in it, 3 weeks passed since recharge, can't locate the leak. I own this car for 2.5 years, A/C was weak all that time, so leak must be insignificant.

Mine A/C system is older one, it takes 35 oz. Label under the hood says: 1kg of refrigerant.

Post by **vtl** » 04 Jul 2013, 14:51

Sigh... My compressor is from pre-Bosch era, it has Zexel label, on it and I have problems with pulling pulley off. Here's the picture:

I can't stop pulley from moving when unscrewing center bolt. Ideas?

draser · Post by **draser** » 04 Jul 2013, 16:55

I see 3 holes in the pulley - you can make a holding tool with 3 prongs just like holding the crank pulley when removing for timing belt job.

Post by **abscate** » 06 Jul 2013, 05:45

Or back out one bolt, buy two longer bolts, and use them to protrude out side the clutch housing.

A breaker bar or tire iron can now be used to hold the clutch from rotating.

Put the two bolts into a Baggie and sell them on ebay as "exact replacement for Volvo tool 666, clutch removal jig" for 29.99 plus shipping

Post by **vtl** » 06 Jul 2013, 06:07

It has only one bolt.

Post by **abscate** » 06 Jul 2013, 20:15

Sorry, my bad. Use two of the three threaded holes for clutch removal for your bar holder

air conditioning not cold RESOLVED, over pressure

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