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Nissan Diesel running hot up hills

Posted: Mon Nov 08, 2004 10:19 pm
by Trav
Does anyone one no of cooling fixes for these things, my work car a toyota 4.2 diesel pulss a tandem with a tractor on it all day long and the temp dosent budge, i drive my nissan moderatly hard and the temp goes up i have put a new radiator in it and there is nothing wrong with the engine everyone i no has the same problem, would a 17 inch thermo by itself keep it cool with no engine fan??

Posted: Mon Nov 08, 2004 11:20 pm
by patrolman
more info would help eg 3ltr, 4.2 etc

Posted: Tue Nov 09, 2004 7:33 am
by 80diesel4play
A diesel only runs hot when they are under load - up a hill at noise is a good example. Unlike a petrol engine where teh fuel is used as a coolant of sorts - a diesle doesn't work that way.

If you're towing and it fine - its probably cause you aren't giving it a heap of rev's. Ging up a hill does wierd things to ones right foot!

Try a set of XR6 twin thermo's they aren't expensive at all - $250 for a set new from some places... They come with a good shroud and will keep the car cool and then some... Single one on its own wont cut it on a diesel - too much surface area not having air drawn through it!

also check the water pump to make sure thats okay as well.

:D

Posted: Tue Nov 09, 2004 7:48 am
by bogged
Singo has pretty much said it..

Its not uncommon for TD42s to run hot when given a hard time...

Check a few things.

Thermostat
Radiator cap
Clutchfan
Waterpump
Radiator Hoses
Have the cooling system completely reverse flushed - you will be amazed how much shit is in the system - then add good quality coolant.

Also check the archives on
http://forum.patrol4wd.org/phpBB2/

Too Hot

Posted: Tue Nov 09, 2004 8:08 am
by Not For Highway Use
I had the same problem. Check the viscus coupling on the fan. Thermo's work but don't like mud and you need a bypass switch for water. Also make sure the the whole system has been flushed. I replaced everything, waterpump, thermstat housing and thermostat. Fixed the problem for me.

Posted: Tue Nov 09, 2004 7:47 pm
by J Top
Check your fan when the engine is hot.If you turn the motor off when the engine is hot and the fan keeps spinning the viscous coupling is faulty.
I have "repacked " several of these with new fluid,just split it add the fluid and reassemble,don't remove any of the existing fluid.
The only time it hasn't worked has been on a TB42,the coupling dosen't come apart.
J Top

Posted: Tue Nov 09, 2004 8:53 pm
by Camshaft1
Have you got a body lift. after i fitted blocks i find it runs a bit hotter. i'll move the radiator one of these days.

Posted: Thu Nov 11, 2004 11:03 am
by Big Red Toy
yeah bodylift can screw things up 4 ya, mine's got 3" bodylift and it gets pretty warm on real long hill climbs, but then again thats foot flat to the floor the whole time :twisted:
Try flushing the system, if its a major problem, during summer remove the thermostat from the housing to prevent further restriiction

Posted: Thu Nov 11, 2004 11:37 am
by hottiemonster
Big Red Toy wrote:yeah bodylift can screw things up 4 ya, mine's got 3" bodylift and it gets pretty warm on real long hill climbs, but then again thats foot flat to the floor the whole time :twisted:
Try flushing the system, if its a major problem, during summer remove the thermostat from the housing to prevent further restriiction


yeah but yours is a petrol :finger:

Posted: Thu Nov 11, 2004 12:06 pm
by Guy
Big Red Toy wrote:yeah bodylift can screw things up 4 ya, mine's got 3" bodylift and it gets pretty warm on real long hill climbs, but then again thats foot flat to the floor the whole time :twisted:
Try flushing the system, if its a major problem, during summer remove the thermostat from the housing to prevent further restriiction


I say that removing a thermostat is poor advice, as they fliud may not spend enough time in the radiator to cool effectively.. you should always make sure you have a good quality thermostat installed to allow the engine to run at the temp's it was designed to run at ..

Posted: Thu Nov 11, 2004 5:13 pm
by J Top
Thats not counting the fact that it is a twin acting thermo, and removal can allow the water to bypass in the housing without going through the engine block.
J Top

Posted: Thu Nov 11, 2004 9:14 pm
by Trav
yeah ill check the fan dosent sound like its comin in, i have a body lift and a turbo running 18 psi i have lowered the radiator to where it was factory had new radiator put in, i guess ill pull the fan off and put some more oil in, see how that goes, thanks for the info.

Posted: Fri Nov 12, 2004 3:29 pm
by John H
My 4.2 has a turbo (no intercooler) and runs 12psi boost. It used to run pretty hot. I tinkered with the fan cluch and it didnt help much. Got a three core radiator made up and it now runs at no more than 1/3 on the temp gauge. At first I was conserned that it ran too cold so I removed a whole bunch of fluid from the fan cluch. The new radiator cost around $600 and I now feel a lot happier on desert trips and long steep hills.