Yet another "My XJ Runs HOT" Post

[wikchi]

well i tracked down my overheating issues but have many others but i think i can help.

First of all try cleaning out everything inside and out, hose the radiator and get a pressure tester.

Then its just a process of elimination.

Water pump working? How well is that flowing?

Whats the engine bay heat levels like would a scoop improve airflow?

Are the stock fans working?

If your unlucky like me issues will keep rearing their heads but u will get it under control

[rainman]

http://www.rmi25.com

Fibres- for want of a better word. Flocks I suppose is what they are called.


Ausi, distributor
http://www.costeffective.com.au/Prod...stem-treatment

Check yr thermostat is working properly?
Otherwise I would be inclined to be looking at water pump and rad.
I had zero overheat probs till I changed out the coolent. And got that flocking problem. Highway speeds overheating after no probs for years, months after a coolent change, well that was my story.
Good luck with it.

[tazwegion]

Originally Posted by xjdavid

Gas will run a bit hotter.

My experience has always been the opposite (unless too lean a mixture), the LPG absorbs heat directly from the cooling system to become a combustible liquid, this process is ongoing (whilst running LPG) with heat continually being removed from the cooling system (via the converter) the operational temperature is less stressed, besides which the thermostat's job is to regulate the running temperature anyway.


I noted this phenomenon most on LPG vehicles with compromised cooling systems, they struggled significantly more to remain cooler on petroleum than LPG.

[LuluBelle]

All interesting stuff guys but the entire cooling system is near new that's what has me stumped could I be that unlucky that another thermostat is on the way out that counting the original would be 5 thermostats in 3 years no I don't even want to think that
I was down 500ml of coolant surely that couldn't send the temps up so much and yes the temp guage might be out but you know when something isn't right don't know what to do at the moment

[Richard buttocks]

Originally Posted by LuluBelle

My entire cooling system is NEW!
and clean as including all the rad air con rad and tranny cooler rad
2 years ago and 4000 klm ago I flushed the block and replaced the thermostat radiator and water pump

so did you replace the radiator 2 years ago?
or 4000kms ago?

[bruggz351]

Originally Posted by rainman

http://www.rmi25.com

Fibres- for want of a better word. Flocks I suppose is what they are called.


Ausi, distributor
http://www.costeffective.com.au/Prod...stem-treatment

Check yr thermostat is working properly?
Otherwise I would be inclined to be looking at water pump and rad.
I had zero overheat probs till I changed out the coolent. And got that flocking problem. Highway speeds overheating after no probs for years, months after a coolent change, well that was my story.
Good luck with it.

So, rainman, what's the deal with rmi25?
Do you use it?
I'm interested if only for the safety aspect. Being non toxic.

Sent from my FRED

[junglejuice]

Originally Posted by LuluBelle

well I just spent hours reading about fans vents scoops hi flow water pumps and thermostat housings and clutch fans now a while back I had issues with getting a serpentine belt size was wrong now I never got around to getting one after I sent the wrong belt back I was reading about the belt slipping and not turning the clutch fan enough and as mine is a bit glazed I have decided to change the belt before I do anything I was going to change anyway cant hurt
if I was going to go with any mods I think it will be louvered vents on the bonnet remove hot air at any speed as hot air rises
it actually would be interesting to take a run with the bonnet off and watch the temp gauge is that legal ?

Louvres and vents don't always let heat out, I had a vented bonnet a while back and did some experiments re temps and airflow.
What I found was that at a certain speed the flow of air through the vents would reverse, at low speeds the air would be out going but this would reverse so on the highway the airflow is from outside to inside despite the vents facing backwards so whilst this was good offroad on the highway it would have a negative effect, this also applied to bonnet spacing as well....

Again, fix BEFORE modification...