I recently finished a complete coolant system overhaul. I replaced all hoses, thermostat, fan clutch, e-fan, e-fan switch in the radiator, e-fan relay, removed the heater valve, installed a flushing-T in the upper heater hose, installed an inline filler neck in the upper radiator hose with a 16lb cap, and an aftermarket overflow bottle. Basically I replaced everything except the radiator and engine. During this process I also swapped my old "idiot light" cluster for a gauge cluster and installed new sending units for oil pressure and coolant temp.

Right now my engine temp gauge climbs to only 150-ish and stays there. I've checked the temp at the t-stat housing with an IR thermometer and it reads 205 after a long drive (about 5 miles) to get her warmed up. When I turn on the e-fan (installed a manual override for that too) the temp drops to about 180 in just a few mins. I would say engine cooling is working properly.

My question is, what can I do to verify proper operation of the gauge and/or sending unit without just buying replacements?

P.S. One other quick question. I am running Mobil 1 5W-30. What is the nominal oil pressure range for an XJ?

Thanks!

 

bump

 

I thought I read that the different dashes had different sending units/sensors.

 

They do. I installed the sending units required for gauges. My problem is that as the temp increases the needle will climb to around the 150 point then stop. I'm leaning towards wiring or a faulty gauge being the issue, but haven't ruled out a faulty sending unit even though its brand new. I was hoping for some advice on how to isolate the fault before I start spending money on parts.