Bizarre. Strange

tommyheadleycox on Tue September 02, 2014 10:27 AM

Year: 1999
Make: Plymouth
Model: Voyager
Engine Size: 3.3
Refrigerant Type: R-34a
Ambient Temp: 95
Pressure Low: N/A
Pressure High: N/A
Country of Origin: United States

Compressor was cycling on and off immediately upon start up. It was impossible to get a reading with the Harbor Freight gauges I bought. Even worse, the HF coupler for the high side/discharge port seems to have destroyed the valve. The cap is providing a good seal, but if I unscrew it, there is an immediate and forceful stream of R34a leaking. Apparently the cap is working pretty well, because my uv light shows no leakage there. (I was able to inject some dye)

Right now, the status is: A/C works from a cold start. Ambient temp: 95 F. Center duct temp 55 F. A/C will work for approximately 20 -30 minutes then stop blowing cold air.

mk378 on Tue September 02, 2014 10:56 AM

When it stops blowing cold air, pull over and check if the compressor is engaged. This sort of problem is usually a clutch gap issue. As the temperature of the copper windings increases, the magnetic force from the clutch coil weakens and won't be able to pull the clutch in if the gap is critical.

At some point you're going to need to deal with the leak and recharge by weight. The cap is designed to hold in full operating pressure, but not being able to use the port is going to prevent you from doing proper service. An undercharged CCOT system will cycle on and off rapidly and cool poorly. This is not to say that every sytem that cycles rapidly and cools poorly is undercharged, it could also be an overpressure on the high side due to condenser problems. Buy a better gauge set.

Dye is kind of useless to identify service port leaks, since a little dye will normally blow out every time the port is used.

Edited: Tue September 02, 2014 at 11:05 AM by mk378

tommyheadleycox on Tue September 02, 2014 11:19 AM

Thanks for the quick and helpful reply. I intend to get a better gauge set. I borrowed a very nice set from Autozone. The couplers engaged and locked on to the ports instantly and without any finagling. Not so on the Harbor Freight set that I later bought for $59.00. They sometimes required manually retracting the spring loaded ring and then trying to line up the coupler so it would engage. This tenuous method eventually destroyed the valve. The set from Autozone may have been Mastercool and are obviously worth the extra money, though plenty of people seem to have had good luck with the HF. Maybe that unusual Chrysler discharge valve (rubber ball and seat) is more delicate than Schraeder valves.

Anyway, thanks for the tip. If it's a clutch issue, perhaps I can address that myself. If there are condenser problems, well ... rats.

Tom

tommyheadleycox on Fri September 05, 2014 9:16 AM

Finally took my Voyager to the mechanic. He said I had WAY overcharged it. Good news: The compressor works MOST of the time. Bad news:
It will sometimes quit. Temporary answer: Pull over and with a very long huge screwdriver turn the clutch and the compressor will start again.
I drove it 250 miles yesterday and had good ac the whole time. Then it stopped at mile 250. Spun it and it worked till i reached my destination at 270 miles.

Now: tough decision time. Love my old van which i use kinda like a pickup truck, but replacing compressor, and related parts costs more thgan than the value of the car!!! What says the forum? SELL, I bet.

mk378 on Fri September 05, 2014 11:08 AM

Try adjusting your clutch. If you can reach the compressor with it installed, you can do this with the system charged. Take off the shaft nut and the clutch plate. Remove some of the shim washers from the shaft and re-assemble. If the clutch drags when it is off, you went too far and need to put some washers back.

Edited: Fri September 05, 2014 at 11:09 AM by mk378

tommyheadleycox on Tue September 09, 2014 12:03 PM

Thank you! I'll try this idea of removing some shims. Can't hurt anything!

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