4.0 thermostat sensor in radiator hose?

[J33ps]

Is this normal??  This truck has a 4.0 from a 99 XJ, I was expecting the sensor to be plugged into the thermostat housing like my TJ.  Seems there’s an adapter on the coolant hose…is that what it is?  Is that okay?

 

I'm about to replace the radiator and water pump.  I might as well fix it this is bad.  I only know TJ stuff so I know this could be a bit different.

 

 

[Eagle_SX4]

That appears to be the Renix era fan temperature switch. Originally it is located in the side tank of the radiator but when you swap to an open cooling system like you have, you need to find a new home for the fan temp switch. 

 

If you are planning on using the 99 fuel injection and harness that temp switch is not needed and could be removed.

 

However if you are going to run the renix fuel system you will want to keep it there.

[pizzaman09]

My Comanche has the fan switch in the lower hose there.  The suspicion was that it was added there when the dealer added AC was installed in mine.  

I realized that the newer radiator that was in mine had the port for the sensor, so I purchased a new fan switch and put it into the radiator port.  The original one that is in the lower hose just remains in place but not hooked up electrically.

[J33ps]

Interesting.  I’ll leave it as is then, thanks guys.

 

Another discovery, this jeep does have AC but he said a hose was clogged and he never got it running.  It has a new AC pump and something else but the hose off the pump is just hanging there.

 

i did not realize the AC uses a radiator of its own, though I guess that makes sense lol.  It’s sitting in front, I didn’t see it till I removed the normal one.  It looks rough, wondering if I should just replace since I’m here.  There are hard lines running out that look pretty rusty.  Think there’s any risk removing?  Like any residual Freon?  Or should I just leave it all for my AC guy.  I plan to have them fix eventually to get it running.

 

 

[89 MJ]

My truck has the sensor in the lower rad hose as well. I’m fairly certain my truck has the original rad in it and came with factory AC too. 

[J33ps]

Nice!  Yeah it honestly seemed like a redneck fix but hey if it's legit I'll leave it.

 

So that piece in front is the A/C condenser and I did some digging and I'm clearly missing a lot more A/C parts than he let on.  Also looks like you can replace the condenser removing the grill.  So I won't have to do any radiator rework when the time comes.  Replace another time!

[ghetdjc320]

Easiest to replace the condenser now with the radiator out and just leave it capped off for now. From your pics, it looks like the lines to the expansion valve and evaporator are just removed and taped. You’ll want to flush out the evaporator and see if it holds pressure. 

[J33ps]

Hmm, how do I know if this is an early style ac setup or if he installed a later model one?

 

is the condenser the same for either?  It’s confusing since nothing in this truck seems original.

[fiatslug87]

What year is the MJ? Put that info in your signature so we know what we’re talking about.

 

Both my 88 and 90 AC MJs have the sensor in the radiator, not the hose.

[eaglescout526]

7 minutes ago, J33ps said:

Hmm, how do I know if this is an early style ac setup or if he installed a later model one?

 

is the condenser the same for either?  It’s confusing since nothing in this truck seems original.

 

It all looks like original Renix/AMC parts. Early or later would be hard to tell but one thing, he didnt install a later compressor as it still mounts the Renix/AMC way and not the Chrysler HO way where the mounting bolts go down into the bracket.

 

What part number is on that condenser?