1974 cj5 temp sensor location on 258

I don't know. Maybe I'm blind. :? I've got this sporty new temp sensor I'd like to install but I can't figure out where exactly it goes. Couldn't find the original one and thought a new one would help me locate it.

Anyhow, I would sure like to know what temp I'm running at by just looking at the gauge. Any help?

 

on my 72 it was down on the drivers side of the block toward the rear of the engine.

Be carefull when you replace it. You will spill coolant. If you are fast you can change them with a minimul amount of loss.

 

Well thank you Hudsonhawk. I checked there and All I've got is the vacuum fitting about center on the side of the block. There is another brass fitting forward of that which is capped off. Think that may be the location?

 

Can you take a pic so we have a better idea of what you are looking at?

 

It will be at the front next to the thermostat housing.

 

http://www.earlycj5.com/forums/showthread.php?t=33528

The tapped holes in the water jacket low on the drivers side are typically used for CTOs.

 

On a 74 there are two ports on the drivers side of the engine that are CTO switches.

The temp sender is in front of the motor towards the top threaded into or right under the thermostat housing. It should have a blue wire with a black rubber boot plug attached to it.

 

I sit corrected - obviously mine had been modified.

I still run a temp sender in that location for my dash guage. I have a second one in the T-stat housing that the FI computer uses.

BTW: if you are converting to FI. The 4.0L T-stat housing will bolt on to the 258 without any problems. The advantage is that is has a boss for the Temp sender built into the housing.

 

I would think that you can put the Tstat in any hole in the block as long as it touches coolant. The only issue I can think of is that far back in the block it may read slightly hotter then it is. Who knows though.

 

Unless your temp sensor has a 1/2 npt fitting, you would need to use an adapter to use it in a cto opening. That might place the sensor portion of the sender outside of the coolant flow, in which case the reading may not always be accurate.

 

Actually the two read quite close. The Dash guage is only a couple degrees warmer then what the Computer displays for the one in the t-stat housing after it heats up. Before it heats up completely the one in the t-stat is reading a lot higher as it should.

 

what purpose does the boot have when connecting to the temp sender? I just crimped on a ring terminal and put it under the nut. Havn't gotten my jeep to run long enough to see if it works yet or not. probably dosn't

 

Found it! Twas right by the thermostat. I don't know how I missed that, I even remember cleaning the grease off it a few months back when I first started this project.

Thanks to all who replied. I just found this sight and do believe I'll be spending a lot of time here. I'll try to post some pics when I get some time.

I also have a '99 Cherokee which is now my daily driver/trail rig and a '46 CJ2A.

This one is going to be my next trail rig. Will undergo some serious frankenstein science over the winter.

Thanks again.

 

It was just the factory plug. GM style I believe but don't quote me on that. It was not held on with a nut it was just a plug. I may be following your method soon as my plug is in rough shape.