Temp Sender

[Akula69]

Does anyone have a picture of the temp sender (at the top rear of the engine) that feeds that dash gauge? I went to pick one up at Advance the other day, and they only have a listing for a temp switch, which looks suspicously similar to the sender that is installed for the 'idiot light'.

 

I know where it's located, just need to comfirm it's appearance.

 

Also - picked up an almost brand new radiator from the JY several days ago..is has what appears to be a temp sensor embedded in the right-hand tank (just above the power steering line). Is this an alternate location for the temp sender, or is this sender for another purpose?

[chicofuentes0224]

Does anyone have a picture of the temp sender (at the top rear of the engine) that feeds that dash gauge? I went to pick one up at Advance the other day, and they only have a listing for a temp switch, which looks suspicously similar to the sender that is installed for the 'idiot light'.

 

I know where it's located, just need to comfirm it's appearance.

 

Also - picked up an almost brand new radiator from the JY several days ago..is has what appears to be a temp sensor embedded in the right-hand tank (just above the power steering line). Is this an alternate location for the temp sender, or is this sender for another purpose?

 

The switch in the radiator is actually to turn on your aux fan when it hits a certain temp. it's connected to a relay on the inner driver's side fender well. Of course if you have no aux fan it won't be there. The two temp senders that go in the back of the head look exactly alike. You just have to make sure you get the one for full gauges. I bought them at NAPA and Autozone. Price was 10-15 dollars.

[Akula69]

 

The switch in the radiator is actually to turn on your aux fan when it hits a certain temp. it's connected to a relay on the inner driver's side fender well. Of course if you have no aux fan it won't be there.

 

When you speak of an aux fan, are you talking about the electric fan on the right side of the radiator? mine is hard-wired into a harness that runs thru the firewall to the ECM. (it appears to be a custom pin change to the ECM). If not that fan, where would anothe be mounted?

 

Thanks

[BLHTAZ]

This is what it should look like...

 

[chicofuentes0224]

 

The switch in the radiator is actually to turn on your aux fan when it hits a certain temp. it's connected to a relay on the inner driver's side fender well. Of course if you have no aux fan it won't be there.

 

When you speak of an aux fan, are you talking about the electric fan on the right side of the radiator? mine is hard-wired into a harness that runs thru the firewall to the ECM. (it appears to be a custom pin change to the ECM). If not that fan, where would anothe be mounted?

 

Thanks

 

 

Yup the electric fan.

[Akula69]

Thanks for the pic, Brent. :cheers:

 

Okay, now you have my attention Chico. Do you have a schematic of the hookup for the relay/fan/sensor?

A picture of the setup would be really good as well. I believe that (the way it's wired now) the aux fan only comes on when the A/C is on...I gotta check that....but using that sensor makes a hella more sense.

 

Thanks Guys

[chicofuentes0224]

Sorry Akula I don't but I think Brent put up an electrical manual up in the DIY forum. I can get you a pic of where mine is but it won't be clear. I hooked up my electric fan up to a relayed switch and disconnected that sensor. The reason it might only come on with the AC is because your engine isn't hot enough to need it. Mine only turned on after my temp gauge was close to the 3 quarter mark. I put it on a switch to run it full time.

Let me know if you want a pic of that area and I'll get you one.

[BLHTAZ]

Yes, the stock electric fan should come on and run at all times when the A/C is on, but only come on when the coolant temp reaches the assigned level to activate the switch in the lower left side of the radiator.

 

AFAIK Jake, you have a hard copy of the manual that I posted in .PDF format on here in the DIY forum. I think you were believing that Chico was talking about something other than the stock fan, but I may be wrong as well.

[Akula69]

Yes, the stock electric fan should come on and run at all times when the A/C is on, but only come on when the coolant temp reaches the assigned level to activate the switch in the lower left side of the radiator.

 

AFAIK Jake, you have a hard copy of the manual that I posted in .PDF format on here in the DIY forum. I think you were believing that Chico was talking about something other than the stock fan, but I may be wrong as well.

 

Yeah, my MJ does not have that sensor on the radiator (that is currently installed) - never did. I also do not have the relay on the inner fender.

 

I have always wondered why the PO had clipped the plug off the fan leads and hard wired in the harness (that eventually ends at the ECM). I suppose thats another mystery I'll have to solve and correct.

 

Does anyone have the specs on the relay, or is it just a common one I can pick up anywhere? (the electrical manual is not real specific).

 

Thanks

[BLHTAZ]

I had to come up with a set up for mine that put a switch in the mewer style t-stat housing and used an adjustable controller for my fan when I put the new style radiator in it. It was a bit of a PITA, but it worked out well. I bought a cheaper controller so it doesn't adjust as well as I would like and I would definitely recommend getting a good SPAL controller if you are going to do it.