Noob question: Evaporator Box Seal

[jeffnhiscars]

Those are r134 adapters . Get a new drier, move your pressure switch over, add 10cc of Pag and charge her up with 32oz

[c0rbin9]

That's the best news I've had all day, thanks jeffn.

Don't I also need one of the R134a-compatible pressure switches if I want to eliminate the ghetto rigged jumpered situation? If I'm reading the R134a-conversion thread right, there is a r134a-specific switch that allows the higher pressures of r134a. I'm assuming my system was converted without using the proper pressure switch, which is why the switch was bypassed.

[c0rbin9]

Also is this the right high pressure switch, part number 64-53-8-390-971-M283?

http://www.pelicanparts.com/cgi-bin/...8-390-971-M283

[jeffnhiscars]

the higher pressure comes from a proper r134 compressor not the refrigerant so if you have a working high pressure switch just use it. Never done a switch upgrade so don't want to give you wrong info.

[c0rbin9]

Gotchya. Probably going to order parts tonight from Pelican.

Anyone know anything about the proper pressure switch to use? I'd like to install the right one at the same time I replace the receiver drier. This is for a car w/ R134a fittings but still the original compressor.

The R134a conversion thread seems to suggest that even with a stock compressor, a high pressure switch is necessary. Is this correct, and if so, where can I get one?

[c0rbin9]

In the middle of tackling this job... wish me luck guys. Trying to make sure not to cross thread my new evaporator valve like I did the original.

[jeffnhiscars]

If you didn't save the rubberized insulating putty they pack around the expansion valve get some rubber insulating tape from an AC supply house. If you don't wrap the valve and the metal connectors it will sweat and cause moisture problems ..ie...wet carpet, mildew etc

[c0rbin9]

Just finished doing this job. I ended up with a new evap valve, receiver drier, and blower motor resistor. Also removed and lubricated the blower motor which proved to be the most difficult part of the job.

I'm glad to have a sealed A/C system again - next step is to charge it up.

Thanks again for the tip Jeff. My car never came with any of that sticky insulation stuff - will definitely wrap it before I charge the system. Hopefully enough of the valve is exposed to wrap it without needing to take off the lines and the box again. It's kind of a pain.

[c0rbin9]

Update: got A/C charged at a shop and the A/C works fine with no more leaking into the interior, or anywhere else that I can see.

Only issue is that the compressor wasn't pulling down enough pressure so he could only put in, IIRC, 1.4 lbs of refrigerant. So it's not really charged optimally and vent temperatures aren't ideal. It's enough to take the edge off in the summer though. I'm assuming the compressor is weak and needs to be rebuilt/replaced.

Perhaps related, the compressor is like a lead weight on this engine when it engages - is that normal for M42s?

[jeffnhiscars]

You don't need to remove anything besides the plastic panel to the left of the glove box and possibly the glove box too to access the expansion valve and seems to me a compressor draws several HP so you could easily feel it on a 4 banger. Good that you are getting some relief from the heat

[PKile]

Those are R134a gauge fittings, so it's been converted at some point. The older R12 fittings look like bicycle tire air fittings.