simspace

Hi All,

I'm trying to remove the A/C evaporator from the blower motor / heater / AC housing on '91 Cherokee XJ (Laredo).
I need advice on how to remove the evaporator thermistor / sensor / probe shown in the pics below.
I have several FSMs and not one shows how it's done. They just say "remove it." But it seems to be "locked" on somehow. Any ideas?

Thanks,
Chris

CCKen

It's probably corroded in place. See if twisting it while pulling on it will break it free - gently now.

simspace

Will do. Is the relay and probe all one piece? Will the entire probe come out of the evaporator? Or does the relay disconnect from the probe?

Thanks!

CCKen

Relay?


What you are looking at is an assembly. If the probe pulls out of that box it's toast so be careful. I've looked for one of these in the past and couldn't find one.

simspace

Oh wow ... so if I understand what you're saying ...

If the evap has to be replaced, the entire box has to be replaced? The wire in the front, shown in the first picture, cannot cannot be disconnected from the evap, to pull the evap out of the box?

CCKen

What do you mean "Evap"? You are dealing with the Thermostat Control.


That box is part of the Thermostat Control.


Why would you want to disconnect the wires from the Thermostat?

CCKen

Here's what a Thermostat Control looks like.


Shown is a Thermostat, part number 55036856, for a '96 RH drive. The one you need is part number 55035503. Same for 91 thru 96.


The one shown is similar to yours.

simspace

Sorry my "wire" post was poorly worded ... but the pic you posted answer my question, the "Thermostat Control" (which I was referring to as the probe) is removable from the evaporator.

This is what I'm having problems removing. The Thermostat Control spins, but I cannot pull out. I think it is corroded in place as you said earlier.

Is there a trick to loosing it? Or a way to break down the corrosion? Or do I just continue gently pulling?

Thanks for your help CCKen!

CCKen

It may help to squirt some penetrating oil, like Liquid Wrench Penetrating Oil, down thru the condenser fins in alignment with the Thermostat probe, let it set for awhile, then gently try to work it out. Repeat application of penetrating oil as required.


Edit: You MUST try and save that Thermostat, they are impossible to find.

simspace

So I finally got it out. It was stuck due to corrosion. Nothing seemed to help loosen it.

I managed to get some needle nose pliers on the probe to twist it out. Not a great idea, but that was the only way it was coming out.

The wiring is all in tact but the probe is a tad ... bent. I'll have to straighten it out and re-use it as a last resort.

I want to convert to R134 since I already need to buy a condenser and drier. So I might as well look into new evaporator options.

I'm hoping there may be a way to use a '94 or '95 evaporator.

Thanks for your help CCKen!

freegdr

Found one.....
http://www.ebay.com/sch/i.html?_from...35503&_sacat=0

simspace

Wow ... Nice find. Thank you!!!!