Outer Limits 4x4 Board

I own a Y60 running a TB42 and live in Dubai where the summer temperature rises up to 55 degrees and I begin to have the problem of over heating, I tried to put in a new thermostat but with no success the temperature just rises more how ever when I removed the thermostat the temperature dropped to the normal status but then again it rises when I am stuck in a traffic jam.
Any Ideas?
I even changed the whole radiator and the cooling fan which works all the time
Also how high can the temp go on the TB42 before stoping it to cool down?

The termostat is there for a reason, basically it's sposed to maintain the engines temp at the recemended level. It does this by either increasing or decreasing the water flow through the motor, by removing the thermostat the water flows at such a speed that it does not get the time in the radiator to cool down..... therefore the temp rises.

With the 55 degree temps you have to endure combined with the city trafic jams the engine is obviously spending much of its time at idle and the only time when it is up in the revs so to speak its when you are going form one set of lights to the next ..... no doubt the engine is working hard between lights, this again is not helping the temp.

Little known fact is the a fan isnt really required once a vehicle is moving beyong 50 kph..... the air pressure at the front is generaly enough to cool the water down.

Back to your problem... sounds like you've done all the changes to date, I was thinking that maybe the radiator cores were a bit blocked but you say youve changed the radiator....
was it a new unit or 2nd hand ?
how many cores is it .... 2, 3, 4, or 5 core job ?
Have you fitted a new water pump ? ( the impellers do corrode away ! )

Things to try....
get a high presure engine flush done....
this will remove any gunk in the head and block that may be blocking the water passages.

Buy a quality thermostat.....
cheap ones are generaly trouble right from the start and never truly work well or for long periods.

Fit an additional fan....
If room allows this an additional fan may help, you may need to fit it on the opposite side to the current unit you are using ( What are you using at the moment engine driven or electric ?? )

In desperation.....
Is there enough room under the vehicle to fit an extra radiator, I've done this before to a light truck that did a hell of a lot of stop/start city driving and it worked well, I used a radiator from a familly sized sedan and fitted up twin thermo fans to it, the fans were up against the floorpan and blew down..... plumbing was a bit of a nightmare but it all worked out well in the end.... I added a micro switch to the throttle so that when the truck was at idle the fans were engaged, as soon as the throttle was opened a tiny bit the fans switched off..... I also fitted an overide switch to the dash so it could be manually operated, this switch has never been used !!

for those interested ..................... it was a garbo's truck ! ( mitsubishi )

Sounds like you may need a larger core rad, and maybe some thermo fans.

You say that the cooling fan runs all the time . . . i assume that u mean the clutch fan on the motor. Maybe check the thermo fan in front of the rad? It should come on when the A/C compressor kicks in. Mine was shagged from too much mud and the temp naturally rose a little when the AC was on in traffic.

Thanks guys for all your great input

The Radiator is brand new from NISSAN and the electric fan infront of the radiator is always on, I got it to work all the time by a manual switch.
The water pump is 1 year old and again it was brand new
BUt I guess I am gona go for the high pressure engine flush and a new thermostate
Any ideas on which thermo to get besides the original one coz I have tried the original one and it doesnt do well

Phill wrote:Thanks guys for all your great input

The Radiator is brand new from NISSAN and the electric fan infront of the radiator is always on, I got it to work all the time by a manual switch.
The water pump is 1 year old and again it was brand new
BUt I guess I am gona go for the high pressure engine flush and a new thermostate
Any ideas on which thermo to get besides the original one coz I have tried the original one and it doesnt do well

When fitting a new radiator, it's always a good idea to add filter(s) to the coolant return line(s) from the engine. Many a brand new radiator has been instantly clogged up by debris from inside the engine.

Anyway. What you want for more cooling is more airflow or more coolant flow.

My first plan would be to improve airflow with an additional electric fan in front of the radiator. A GOOD one, not a cheapie.

Next and much more of a hassle would be an electric water pump, to get the coolant moving through the system faster.

My gut feeling is that an additional electric fan will do the job.

Oh. It's also important to ensure that all the cowlings are well fitted and sealed. That is, the fans must have no choice but to push/pull air through the radiator. If this isn't done properly, the air will instead follow a less resistant path, passing through the fan but going past the radiator.

Jason

it could already have sustained a blown head gasket. making any overheating problem worse.

Where is it coming up to on the temp guage about? On a hot day here (up to 42deg) my temp guage comes up to just below 1/2 way and when working hard, just a bit over halfway but then i can hear the fan clutch cut in-and feel a slight drop in power, and temp gradually comes down.

Make sure that FAN clutch is working properly and you can feel it and hear it sucking plenty of air through the radiator, water pump is ok--ie blades not worn out,ignition timing ok,the radiator shroud is on properly and the sides are sealed up to prevent air leakes. On the diesel, there are rubber flaps where the radiator mounts to the support panel to prevent leaks--check that yours has these added and that they are working properly. Are there obstructions in front of the radiator?--ie large driving lights. What temperature thermostat were you using? I think ours over here opens at 76degC I havent had any problems with the Factory Thermostats.


Nick

During the normal summer days when I am driving on the road it will hit half way!
When I am in the dunes pushing its limits then it would go 3/4 but will not the touch the really hot line
In winter it is below the 1/4 in all conditions
Note that in winter the lowest tempreture here is 20 degrees

hrmm.....my temp needle never moves once its warm. just stays a bit more than 1/3 doesnt really matter what its doing

Draven wrote:hrmm.....my temp needle never moves once its warm. just stays a bit more than 1/3 doesnt really matter what its doing

Mine used to be like that...