I was having some cooling issues with a 96 Cherokee Country 4.0L. We found hydrocarbons in the coolant so... off came the head.

After getting the head out of the machine shop we found out the head was cracked in multiple locatins. A new head was ordered through pep boys (employee discount) with the same casting number (0630).

The new head was replaced and everying went smooth, but when it came time to plug in all of the sensors, the coolant temp sensor on the back of the head wouldnt fit! Its just a tad too long. Has anyone else this happen? What are my options?

Its a bummer we went to all the work to replace the head and everything and now can't read the temp! The jeep runs great though.

Any input is much appreciated, thanks!

 

To long ?

 

How have you verified this?

 

From some less than enjoyable experience...I will tell you that aftermarket sensors are a gamble. Their readings are often only accurate to within 10-15 degrees sometimes. Are you trying use the old sensor? Replacement sensors have a bigger head that gets in the way of valve cover at certain spots. The top will sheer off from the brass threads well before it is screwed in enough to sit flush with the head.

 

I know the factory sensor is too long/deep to fit in the new head because I took a grinder to it, shaved it down a quarter inch and it fit great.. I destroyed the sensor of course haha.

I was at autozone for a half hour comparing jeep coolant sensors and nothing looked like it would fit. I wonder what year of jeep this new head originally came from.. is there a way to tell?

I'm going to have to run an aftermarket gauge (autometer) from the upper radiator hose if I can't get the factory gauge figured out. But I'd much rather have the factory gauge working.

 

lol. I have '98 engine in my '92. Coolant gauge sensor was on the back of the head, new engine doesn't have a spot for it... I ended up going with an autolite gauge and put it in block where the renix engine has the temp gauge sensor. Works fine for me, verified with an IR gun to be +/-6* off at times.

 

Where exactly is this spot on the block? Maybe I will look into this.

 

Hmm, image won't hotlink. Try this link instead. http://www.lunghd.com/Tech_Articles/...nt_For_ECU.jpg

 

Here is a pic of the sensor after I shaved it down, and it fit. The other threaded thing is the plug that came in the head.

 

Strange. 0630 head came off 96 - 98. Is your 96 odb1 or odb2?

 

Thanks for the pic! I'm definitely going to run an aftermarket gauge there. Do you know what thread size that hole is? I'm assuming ill need an adapter for my sender to fit?

 

1/2" NPT

 

100% sure of that? Howzabout 1/4" NPT?

 

DONE!

Thanks for everyone input. Especially sthon for the image.

With all of the people replacing the heads in their XJs, I hope this thread helps them out. About half of the time, people will have to find a new alternative to a water temp gauge after installing a new head.

I ended up using the plugged hole in the block to run an Autometer water temp gauge. For now, the gauge is mounted on the steering column. In the near future I see a dual pillar pod with a trans temp gauge.

Keep in mind, the temp will read a little high, as this is the hottest part of the coolant circulation. It read about 210 at idle/city driving, and 205 cruising on the highway.

Here are a few pics!

 

This is what i did when i put a 98 engine in my 91. Keeps the stock temp gauge in play=D