receiver/dryer is cheap, replace it. Water should not be in the system (that's what the dryer is for, to keep it out). To flush system, an alcohol is used.

In the GoldBrick (my 86 syncro), when I converted to R134, they actually had to replace the evaporator, cause it was all gunked up. If your low side is too low, you have a clog someplace on the "high" side. Your mechanic has eliminated the condenser, but you still have the hoses that go from the condenser to the compressor, the host from the evaporator to the condenser, and the evaporator (not to mention the receiver/dryer.)

On Sep 4, 2011, at 11:46 AM, Karl Wolz wrote:

> '85 Westy with 2.1L, using R-12
>
> Only blowing around 80 degrees (better than 112, but not by much), mechanic
> says 300lbs high side pressure and only about 10 lbs low side.  Says he
> suspects a blockage "somewhere".  He drained the R12 and blew through the
> condenser - says that's clear.
>
> Due to my ingnorance of things AC, the hoses were initially hooked up
> backwards at the compressor.  Mech says running the system in reverse may
> have damaged the receiver/dryer, causing these symptoms.  Last night I
> pulled out the expansion valve and am able to blow through it.  AC parts guy
> says that means little, as it could be locked open or closed (this means
> little or nothing to me [I feel like Rocket with this series of questions]).
>
> I bought brass fittings last night with which to hook up a garden hose to
> the system (sans compressor & receiver/dryer) to hopefully flow out any crud
> hiding in the system, with the logic that any water inside will be boiled
> off when a vacuum is pulled prior to recharging.  Anyone care to comment on
> the wisdom of this procedure?
>
> Hoping for cooler air,
>
> Karl Wolz