Overheating 4.2 Turbo Diesel DX Nissan 1999

Stuart,
Heaps of things to check. Could be a simple fix or a combination of many.
check the following things...
Clutch fan ( make sure its cutting in when its should )
Radiator for blockage internally
Radiator for blockage externally (mud built up and dried through cooling fins)
Water pump
Thermostat opening at correct temp
Belts for proper adjustment
radiator cap (holding its pressure)
Hoses not sucking closed at high revs
Check hoses for kinks.

Mate i could go on but its a start, dont panic though. The chances are its not a major problem ok. Although its hard to say when you dont know the history of the vehicle and what the previous owner did to it.

Good luck
Hope you sort it out soon.
Cheers Angelo

Stuart, I'm not sure which state of this grand country you are in but.........there have been a fair number of problems with overheating 4.2 turbo diesels in WA. was originally put down to the fuel but that was discounted. They do tend to run on the upper level of the guage especcially when towing or working hard. Talk to Nissan they are aware of the problem. If they refuse to help then try talking to some of the 4wd places in WA. rgds

I'd be considering the clutch fan as a prime suspect.........
When they cut in, you can really hear the extra fan noise. If you cant hear this and its hot I'd be looking at a new viscous fan hub.

G'day Stuart and others,

Okay, I've had my share of "over-warming issues" (as I prefer to call them as the truck has never really overheated as such).

Mine is a 2000 4.2T/D and it used to go above half way on the temp gauge, even on a coolish day, if I was pushing it hard into a head wind, or up a bit of a hill &/or towing the camper and trying to sit on about 110klicks.

These are the things I tried:
Had radiator flushed etc.
Added an extra electric fan in front of air conditioner condenser, beside the factory one, which I can switch on myself (no change)
Took off the plastic air dam under/behind the radiator (no change and have re-fitted)
Moved the spotties to top of bullbar (no real change)
Cut a hole in bonnet above turbo and fitted scoop off a 3L Patrol (no change)
Bought a new genuine Nissan fan clutch assembly (about $320-)- (no change)
Bought a new aluminium radiator from PWR (Qld) for $1100-....(success)
The new radiator is twice the thickness of the plastic nissan one.

Note that it could still be a problem with the fan clutch as I have NEVER heard my fan cut in on this vehicle, which I owned from new. This is in stark contrast to my last Nissan GQ Diesel (with Safari Turbo), which used to roar out very loud as I went up a steep hill and didn't spare the right Blunnie. So maybe both my original fan and the new Nissan one were both no good.

The temp gauge never went into the small zone on the right marked "H", but once it went above half way, the blasted air conditioning would switch itself off and tempers inside would become frayed.

If your mate is interested, PWR have a web site: www.pwr.com.au

Good luck

Tell him he's not Robinson Crusoe with overheating problems with a Nissan!

G'day, I have a 2000 DX GU ute and have never had the over heating problem, but I have heard all about it. To prevent it happening I have fitted a MTQ modded turbo and an EGT gauge. I now have 120kw at the rear wheels and run a lot lot cooler EGT than standard GU. If you haven't got an EGT gauge, then you can have no idea what your EGT is. It is very easy to over fuel the 4.2TD and raise the EGT to dangerous levels and over stress the cooling sysytem. I would suggest that he looks at the other things mentioned, but also try an EGT gauge, he may find that it is high EGT that is causing his problems. Just my two cents worth.

Brains Trust,

Keep all those good thoughts and ideas coming.....I am passing onto to my mate to try. He is travelling to Longreach as we speak.....any thoughts on who he should go too while there to help solve this problem.

Regards,

Stuart

Lot's of good answers here.
I would look 1st at the clutch fan. These are possibly the biggest single cause of overheating.
Then go down the list from there but do check it is not being overfueled.....
My ancient GQ with aftermarket Turbo puts down 122kw at the rear wheels but runs cooool EGT ie: it is not being overfueled. It runs 12" boost. The guy who installed and modified my turbo says setup is very important and a common cause of problems.

Radiator is ORIGINAL ie 13odd years old and is quite corroded externally on the bottom fins.
Yet I recently towed my 2.5 tonne van up the Toowoomba range, on a very warm day with the aircon flat out- and didn't go much above half-way on the gauge!
BUT I must add the clutch fan is working very well and can be heard roaring when the going gets hot. I added new silicone to it a while ago AND did a mod on the bi-metallic spring to get it to cut in earlier.