Ok i have a 96xj with 4.0 auto. with idiot lights for water,oil and volts. I have changed over with aftermaket gauges. The oil and volt gauges work fine but can't fine a place to install water temp probe. I have two sensors on the motor that are stock , one is on the back right corner of the head 1/8" thread and the other is in the water inlet on the front 3/8" thread. If I remove the the one on the front of the motor it will not start, I believe that one is for the CPU. The one in the back I believe is for the stock idiot light. The probe that came with the gauges is too big for the back one. So now my question is were can I install that probe and is their any aftermarket product that adresses my problem? Thank you for any help

 

The one in the back is the correct one. Easiest way is to get a sending unit that fits. A jy one out of an xj with real gauges may or may not work or just get a new one for that kind of xj. Depends on the resistance reading for the gauge. Probably will work.

 

I've installed them 2 ways in my Jeep. The first was to tee into the tstat housing where the ECT goes. It works but looks ghetto.

When I replaced my tstat housing I drilled and tapped the new one to accept my gauge sender.

I don't like pulling the OE senders because it makes the idiot lights come on or things on my dash not work and then I have to pull bulbs when it is just as easy to do it right.

Old and ghetto (Not a great pic but you get the idea):


New:


You can buy them pre-tapped but they are a rip off. It is cheaper to buy the OE housing (which the drilled ones also use) AND the tap/drillbit combo at Lowes.

 

My guess is u have a mechanical coolant temp gauge and those have a really big sending unit. Usually, electric temp gauges have a much smaller sending unit thus easier to mount. The sending unit in the pic above is for an electric temp gauge.

Mounting the sending unit in the 3/4" heater hose close to the t-stat cover is another option. I've fashioned copper/brass nipples to mount sending units in cars/motorcycles.

 

Thanks alot guys, all look pretty good. Don't know which one I will be doing for sure. The probe is a little long so I don't know if it will work on the 3/4" heater hose or not ,but I will check it out. All ideas are great and I thank you all for your help on this.

 

Using a female/male adapter will shorten how far the sending unit probe extends into the pathway of the coolant. That pic of the electric sending unit shows the sending unit screwed into a adapter....the adapter is then screwed into the t-stat cover. The adapter appears to be 1/8" female 1/4" male.