Changing evaporator on 02

So, I got around to using my cheap, used, refrigerant reclaim unit and took a whopping 9.5 oz of r134a out. So, that tells me some 12 or 13 oz have gone missing.

My immediate question is if it is safe to drive with the evaporator removed and the cables not connected?

Why? The evap was full of critter nest, the fins are pretty well clogged and there is a oily spot in one corner with a dollop of greenish yellow, just for contrast, I guess.

So, while on is on order, I still need to use the truck. Can I? without damaging electrics, etc?

Next question is, the only other place I see traced of dye are where the hoses connect to the compressor. Each of the hold down fasteners have a trace of dye at the mating surface and around the head of the fastener. Question is, should, might, o-ring replacement fix that?

There does not a trace of dye behind the compressor pulley, so I guess that means the seal is not leaking at all?

 

yes you can drive her. I would put some corks (rubber or cork) in all of the open refriderant lines... you can get these at the Home Depot or Lowes. I would replace the receiver dryer while you have the system open. I am assuming that if yoiu have a recovery unit you probably have a vacuum pump and I use that to locate leaks... cork the lines, run the pump until 30" vacuum shut it off and see if the vacuum drops. If it does, disconnect the next closest fitting, plug that and repeat. 99% of the time, at least for me, the issue of small leaks is at the compressor, shaft seal or lines.

 

Thanks. I just walked out to look and the only connectors that are actually disconnected are for the fan resistor and the glove box light. Which is burnt out.

I have the ends of the lines going to the evap wrapped in glad baggies with some absorbent paper packed in, and tied wrapped closed and secured to the frame.

The receiver drier is on hand, as is a new expansion valve. I am pondering changing the pressure switch and pipes for peace of mind, as they are a bit crusty. The fan resistor I will change also as there is some green on the exposed conductors.

When I changed the condenser last year, I added oil with dye in it. When I evacuated it then, it held vacuum for a half hour, so I called it good. As noted the only places I see dye are in a corner of the evap and around the hose mounting to the compressor.

 

If you see dye at the connections to the pump I would just replace the orings. They are cheap and easy to replace. I would also recommend replacing the low pressure switch, the pipes is your call. After you replace everything make sure to put it under vacuum for at least 30 mins, then wait to make sure it holds vacuum and there are no leaks. Also make sure when you reinstall the evap box to route the drain tube through the floor and out the bottom of the truck, otherwise you will have very wet carpet.

 

Thanks. i ordered the pressure switch shortly after i looked it over again. seems prudent given where it is located. after market hopefully is good enough?

 

Aftermarket electronic parts are a gamble. May not work correctly or not last long. I'd be more confident in the original Toyota part working and lasting longer (given that it's still working fine now) than a replacement aftermarket switch.

 

I hear that. I just get tense paying $50 for something that I can get at Rockauto for $20. If the switch were more accessible, I would just leave it and replace it if it ever failed.

 

New after market evaporator is in. Comes capped and sealed with orings. Should I flush it anyway, before putting it in?

 

there should be no need to flush it.