djb383

While you're at the parts store: Maybe a new (not rebuilt) water pump, T-stat housing, fan clutch, rad cap, temp gauge sending unit, ECU coolant temp sending unit, top/bottom rad hoses, heater hoses, serpentine belt, 3 gal. 50/50 coolant. +/-$150 in parts gets u an almost a complete new cooling system.

Another $100 gets a new radiator then u would have a complete new cooling system, could git 'er done by this evening and enjoy one of the best knights sleep you've had in a while. Take your sweetheart out for Valentines Day and not give the XJ a second thought (for a little while anyway).

One other thought, buy bulk heater hoses (5/8" & 3/4" ID) a little long. That way u can eliminate the problematic factory heater control water valve at the firewall in the factory heater hoses. The factory eliminated it starting with '97 models.

XJ5150

Gonna take me longer than tonight to get all that done... gotta get the money first lol

XJ5150

Well we can put this to rest... had to have been the cold outside temps cause today was a T-shirt and Shorts day and I made sure to keep an eye on my temp gauge... This is where it spent most of its time.

mr baer

Mine sits on the 170 line in winter and sits on the line on the other side of the 210 mark during the summer. Doesnt help weve just had the hotest month on record here.

djb383

Hummmm, fixed itself.

gpXJ

Mine sits at 210 once it warms up (even in the below 0 wind chills we had last week). It will occassionally creep to the next tick over when I'm sitting in traffic on the hot Texas roads in the middle of summer.

My guess is the PO put in a 160 degree tstat cause they read some internet myth that it would run better that way, or because there was a cooling system issue they were trying to cover up before they sold it to you.

XJ5150

No, it just warmed up outside. I figured this would happen if outside temps were higher.

redmuck

keep an eye on it when its 80 or 90 outside or hotter it might shoot higher up.

XJ5150

I will... I am still going to replace the thermostat since I don't know what is in there or how old it is. I am still researching this whole heater thing... people saying they have heat as soon as they start their engines kinda makes me go hmmm. I know that if the coolant is still cold... there is no heat. So I think some people are misleading what is going on. If you have heat when you start your engine then it was already warm. I know I don't get heat until my engine is warmed up and the thermostat opens... even if I have heat selected and the fan on high... it will just blow cold until the hot coolant is allowed to enter the heater core... by way of the thermostat opening.

96_xj

with the heater you will not get heat until you get warm coolant....

And replace the Thermo stat and do a REAL good system flush. and you should be good to go

XJ5150

Correct me if I am wrong but to flush the system, the tstat needs to be out right?

96_xj

you can do it in or out.

also make sure you back flush the heater core and replace the coolant lines

XJ5150

It has a new heater core... though I think the lines are not new.