Yet another "My XJ Runs HOT" Post
 

yes it runs HOT! and I have no idea why?????
went to Barcaldine yesterday a nice little 106 klm drive through central QLD average temperature was around 34
Speed Limit 110
Sitting on 105 cruise control at 2100 rpm on LPG....(new spark plugs)
Average temperature on the way there was whats the first notch past the 100 mark 110 deg?.....
I was in Barcaldine for about 15 minutes picked missus up from the train and then stopped to get a drink and then back on the highway heading home about 50 ks out the temp was up neat the RED!! NO AIR COND!
I watched for about 25 k and I dropped out of cruise control as my revs had gone up about 200 rpm now on 2300 at 105 kph
WTF!!
I have owned the XJ for about 3 years and have fixed a few things over the years
I have a new OEM radiator
new water pump
new hoses
on my 3rd thermostat had issues last year on the way to Brisbane
new heater tap and hoses the block has been flushed I use coolant the clutch fan seems ok?
engine stopped try to turn clutch fan give a push might move 20cm lots of resistance

As I have LPG I noticed that there are a In and Out coolant lines to the gas converter................
I googled LPG cars overheating Nothing
I guess that the hot coolant helps the LiquidPG expand to a gas for the engine as it is stored cold under pressure my guess anyway
So why am I running so hot?
I have a transmission cooler every thing is clean only have a 13 inch light bar so there is plenty of AIRFLOW I am at Witts end?
Now after reading wikchi s post about overheating and stalling I saw people talking about different Clutch Fans gc? are they brands of fan? haven't tried to look it up yet
I have also read and seen on youtube about having multiple electric fans no clutch fan I would like to run at 100 105 on the highway I have seen scoops vents even removing the bash plate don't know how that works
Input Please people any ideas
Im thinking about the electric fans can I splice into the existing fans power and earth wires
help
:hammer:

Electric fans wont solve your problems.

Try replacing your clutch fan and make sure your stock electric fan is staying on.

Also do the basic checks like is there gunk/dirt/straw/dust in the radiator cooling fins? Try cleaning the outside of the radiator with low pressure tap water out of a hose then a pressure washer if it doesnt clean the gunk out.

Cant help with the LPG issues as its not my forte but if the system is not running right that would cause problems with overheating i would imagine.

Consider a rear facing hood scoop like i did ;)

Fanclutch is mostly involved in overheating at slow speeds, not so much at highway speed overheating. Those would be more the likes of : blocked radiator, bad waterpump, thermostat, air in system, too low coolant levels etc.

So, you have had NIL recent running hot/ overheating issues until that last trip??

Keep in mind that verification of the temp is one of the first steps. You might be chasing a ghost otherwise if it turns out your temp sensor is just kaput.
Because its somewhat strange your temps all of a sudden would be that high.

A ZJ clutch fan is stronger.
There are coolant lines to your LPG regulator to stop it freezing up as it turns the liquid into a gas.
A lean air/ fuel ratio can make an engine run hot.
I like bigger than standard radiators.
Bonnet vents help extract hot air.

Good luck with it.

Good idea of the temp sensor, i am sure mine is kaput but i can tell when my car is overheating

I'm sure you can, the signs are usually obvious:
Pic 1 would be: I think its "Running Hot"
Pic 2 would be: I think its getting " In the Red"

I had overheating issues plague both my XJ's at some point in time. I tried a number of fixes but inevitably the cure was to ensure EVERY component in the cooling system was healthy. The last issue I'd had was a new radiator cap from Supercheap wasn't doing it's job, replaced it with one from Bursons...problem fixed.
So even the most minor of components can screw you over!
You shouldn't need to go to extremes to keep the XJ cool, just the basics.

One incident that caused me some grief was after replacing a water pump the XJ started running hot, it had not run hot prior but the pump needed to be changed because it developed a leak.
I had another near new radiator handy, swapped it in and problem solved. The diagnosis was that the increased flow from the new water pump must have dislodged some crap in the block and clogged the existing (very healthy) radiator...Grrr!

In summary, what I'm saying is don't try fancy mod's to fix the problem, just go over all the factory components systematically and you will solve the over heating.
Good luck :)