My td keeps overheating when on a bill underload have tried everything just got a new thermostat to put in see how it goes but what else could it be

Here are 149 pages of info on overheating 4.2.

Engine running hot TD42???

spent hundreds if not thousands trying to stop it running hot ??? well i have the answer for you and it is fairly cheap , no need for multi pass alloy radiators or anything like that , although i do recommend that all cooling system componants be in good running order this fix is for most if...

www.patrol4x4.com

 

Here are 149 pages of info on overheating 4.2.

Engine running hot TD42???

spent hundreds if not thousands trying to stop it running hot ??? well i have the answer for you and it is fairly cheap , no need for multi pass alloy radiators or anything like that , although i do recommend that all cooling system componants be in good running order this fix is for most if...

www.patrol4x4.com

With respect the all the contributors, myself included, there are no answers in there. Lots of theories and experimentation, but no answers.

 

You need to provide more info. Temps, where you're measuring them etc.

 

Not sure just going by heat gauge

 

I recommend getting an aftermarket gauge.the factory ones can vary alot and it's hard to know what temps you're seeing exactly. What sort of hills are we talking? Long mountain ranges or just regular hills on the highway? Some ranges used to put me up near or on the H mark and at that temp I am probably at around 105 degrees. It's hot but Nissan reckon it's good to 118 degrees. Are you dropping down a gear or labouring in a high gear etc?

 

Dropping down a gear and just your normal everyday hills

 

Suggest you do a search, and look for the thread by Mike Cooper, focussed on cooling system airflow. It is the single most effective method for improving your cooling system that there is. Getting airflow through the core of your radiator is most important.

Apart from that, every component you have must be in good condition and be of suitable specification. Got a cheap water pump off ebay, or a no-name 27 core fancy radiator that somebody's cousin on Facebook said worked well on his Lada Niva??? This stuff may not be helping your cooling system. Nor will broken fans and radiator shrouds, or worn out viscous hubs, and leaves stuck between the condensor and radiator.

OEM spec radiators and water pumps are sufficient to do the job for the average engine. If your TD42 is very high performance, then an aluminium radiator will offer some thermal efficiency advantages over copper. But without getting your airflow right, it will not do much on its own.

 

My td keeps overheating when on a bill underload have tried everything just got a new thermostat to put in see how it goes but what else could it be

Cooling system efficiency is not a single fix. It involves many components working correctly. As stated above, air flow is the most important however i.e if your radiator is blocked then air flow will do very little...and so on. Quality components is another big factor. High flow pumps, 3 core aluminum radiators etc won't do jack on their own if they're not working in unison. And, all this assuming that there are no other mechanical issues head gasket etc.