overheat............sometimes

[joe_peters]

170-ish? No thermostat? Should run about 205-210 normal temperature with a 195 thermostat.

 

[rifle6]

thats where the gauge says,middle is 210 so i'm guesstimating a little.
whats the lowest thermostat they sell? i"m thinking i bought a 180

 

[carves]

well, that did the trick, i road tested it for about 30 miles, it was cool out tonight, but i ran it about 60 miles an hour, and it never got over 170 ish.

it might be my imagination but it sounds and runs better, even a little more power.
so it was the fan clutch and radiator, when i pulled the old one out it weights about 25 lbs more than the new one. must be full of crap.

running about a 40-60 mix .

thanks for all the help.

300 dollar fix includes:
radiator
cap
water pump
fan clutch
new hoses
4 way cross for heater hoses
thermostat
test head gasket

cool running XJ................priceless!!!!

AH haaaa .... welcome to the world of " Fine Tuning " your cooling system ...

Now that you have a radiator that works, a suitable ant-freeze mix for your conditions and a bunch of new parts to compliment that .....

You need to address the running temp.

Because of the barely adequate factory fitted cooling system ... most presume 210* to be THE XJ temp.

What temp do YOU want it to run at ??? ... Mine is quite content in the 190*-200* range and generally sits on 195* regardless of conditions - since the last maintenance schedule.

I prefer a lower temp so that if something goes wrong - like a blown hose/dodgy radiator cap ...

Its spikes FROM 190* to 230*+ .... rather than FROM 210* to 260*+ ......

Just gives that extra little bit of time to switch it off before major damage ...

Utah in summer ?? .... If you can find a 188* or 192* thermostat to go with what you now have .... I reckon you will be happy. Dont ask the counter bloke for a 188*/192* XJ thermostat tho ....

Give him your old one and demand one the same/identical shape and size .... but in 188*/192* range.

If you want to stick with popular concensus .... get a 195* thermostat.

I wouldnt recommend the factory 195* thermostat tho ... unless you want the restricted coolant flow it provides up until about 220*.



Your cooler running temp ... a smidgin more power .... and a increased fuel usage .... but not as increased as many believe.



$ 300 ....... :doh:

Cant get a decent radiator for that price down here .... :tears:


Cool running XJ ... in closed loop, no change in fuel use, no O2 sensor CEL, No "engine too cold" DTC .......... at 190* ... Hilarious

 

[BLU-125]

Also, torque convertor not locking up can cause increased operating temperature, especially if fan clutch isn't good.

 

[rifle6]

I'm going to run it this afternoon while it is 95 degrees, put it through a slight workout on some rock. And highway.

If it stays at 170-180 I am very ok with that. Utah summers are HOT. Come winter I may bump it to a higher temp

 

[rifle6]

road tested in the heat of the day, never got hotter than 170ish.
life is good

 

[jackate]

If your radiator is old or original, I would replace it. I had the same symptoms and checked out everything but the original radiator.

I waited to long and overheated bad. The only repair mishap I every had with my jeep, was failing to replace the radiator in time.


I looked at electric fan relay, thermostat, water pump, fan clutch, lower radiator hose, and it turned out to be the radiator all along.

I think the jeeps came with single core radiator and a double core replacement radiator is better.

 

[rifle6]

ya.