Outer Limits 4x4 Board

Ok well spent the morning doing thermostat related things.

Brand new genuine nissan thermostat is set to 76.5deg C. It is quite a well made piece of kit as far as thermostats go and reasonably priced (just over $30). Also purchased a new gasket which nissan have changed to a metal composite rather than the old paper gaskets.

The thermostat removed from my vehicle was an adjustable item..!



As you can see, thats the thermostat sitting at room temperature. Someone has adjusted it to stay slightly open all the time (bad.. and why mine never seemed to get hot)



Anyway you can see easily on the adjustable thermostat how to keep it open further. Up the top of the assembly you can just see how there's a nut head and some thread which attaches to an adjustable stopper for the wax-pellet driven rod in the centre of the thermostat body. You screw that stopper up a bit to make it open later. this example has obviously been wound down a bit to push the thermostat open all the time.



Here are some clearer pics of what to do if you don't have an adjustable thermostat.

This is a genuine nissan, brand spanker thermo if you go and buy one for a 93 GQ 4.2L diesel manual.


Here's the friendly little blighter you need to shorten in order to make the thermostat open later. Be weary, on the genuine nissan item this appears to be a rather sturdy little rod of stainless steel.


So there you have it.

My GQ now runs with the temp gauge pretty much spot on half way on the factory gauge. It runs MUCH quieter, smoother and has more power in normal driving duties. Oil pressure has remained pretty much the same, if not a tad higher (factory gauge and sender which is a bit flakey).

Its around 28deg C in brisbane today and I didnt see the temp gauge move at all where it normally does (100km/hr in 4th gear, fanging up a steep hill, fanging in the traffic light grand prix etc). The viscous fan didn't turn on anywhere near as much as it used to - infact i didn't hear it engage once. We did stress test it by idling up at a standstill with aircon on in the driveway to see how hot it got, and just as the gauge started moving up above the half way mark the fan would kick in and remain on until the gauge dropped to about 1/3. Turning the heater on, the gauge simply just dropped down to 1/3 - oh and it actually works really well now.. just what i want in summer lol )

Sorry for the long post. I'm quite happy with the results of this small modification. I'll keep you all informed as to how it copes. I'm sure there'll be no problems - most of my cooling system has been replaced in the last year (rubbers and pump) so its in pretty good nick. I am still using the original BRASS radiator protected by an aircon radiator thing, flymesh, original 93 spec grille with no nissan badge and a bullbar.

Big cheers to "its a ford not a nissan" for this excerise. I hope it helps others.

Great post yom. Good to see some useful tech with photo's and results.

Coxy

PS. (put your digital camera into "Macro" mode with the flash off for those close photos buddy!)

It was. I was using my nokia N73 which explains the pictures sometimes working and sometimes not.

Short update.

So far so good. Gave it heaps up mt cootha today (2 runs in 3rd gear @ 2800rpm and then 2 runs in 4th gear @ 2000rpm). Gauge moved up to just above horizontal and then the fan would kick in and the temp would go down again.

Gauge doesn't move much on the highway anymore. Cruising at 100 it sits just below half. Crusing at 110 it jumps up to exactly half. Thats with aircon on (i dont have any electric fans for my aircon, its all up to the viscous!)

Engine heats up within 10 minutes of driving gently under 2000rpm.

Looking good...! I owe someone (its a ford not a nissan) more beer!

See how smoothly it runs tomorrow after the valve clearances are done.

how much do you shorten it by?

sounds like i got the exact same problem as you yom mine takes ages to get heat into it and stays on about 1/3 on the gauge and doesnt move from that. Where abouts is the thermo located on the td42 (only had the car couple weeks)

cheers dez

Something I noticed on mine this weekend whilst fiddling about.
The radiator hasn't been lowered 2" to allow for the body lift.
The shroud has been lowered, this means that the top 2" of the radiator isn't really being used.
The back is blocked by the panel holding the shroud.
It also means that the bottom hose is half kinked at the bend.
Kinda seems like I SHLD be having problems but am not.
I'll get some coolant and trim 2" of the bottom of the bottom hose.
That should improve flow a tad and let the Thermostat do it's job properly.

DEZ wrote:sounds like i got the exact same problem as you yom mine takes ages to get heat into it and stays on about 1/3 on the gauge and doesnt move from that. Where abouts is the thermo located on the td42 (only had the car couple weeks)

cheers dez

Don't delay. Grab some demineralised water, a new gasket from nissan and a new thermostat. As I mentioned the genuine nissan thermostat looks like it might be the best flowing design available - and I figure it may as well have as much flow through the thermostat as possible when it opens itself right up (there's other things which will restrict coolant flow in the galleries of a TD42 but you do what you can when you can).

Thermostat is under that top radiator pipe thingo which bolts to the top of the engine - 3 bolts. Be careful, its all soft alloy here. It would be very easy to warp or scratch the surface. Its a very easy job. Bleeding the GQ is simple, just point the vehicle nose up hill if possible, fill what you can of the radiator, squeeze the pipes a few times and then let it idle for a bit while adding water. I think. Might want to double check on this before you go doing it

Anyway see how it runs with the genuine nissan thermostat. If you still think its running too cold then you can start modifying things. I admittedly went in a little head-strong by going with the modded thermo straight up but hey, I've got a habbit of biting off more than I can chew.

Remember to give it heaps - stress test the hell out of it once you're sure theres no air in the system. You dont want to be 300km away from home and for it to start boiling.

Goodluck!

I would also be keen to see some pics of what you done to the bull bar

sounds like a plan can i ask where you got your thermo and gasket from like a repco or a nissan parts dealer. what prices you get

thanx dez

gday guys. finally got my desert cooler rad. massive aluminium 4 core etc etc. guess what it has solved the problem. couldnt get it to run over 93 degrees (on 2 a/mkt guages)with a trailer full of tools, gerni, etc up the steepest hill i could find in the middle of the day.

she will be at the all terrain and not a smoldering mess after all.

good luck,

purplebus wrote:gday guys. finally got my desert cooler rad. massive aluminium 4 core etc etc. guess what it has solved the problem. couldnt get it to run over 93 degrees (on 2 a/mkt guages)with a trailer full of tools, gerni, etc up the steepest hill i could find in the middle of the day.

she will be at the all terrain and not a smoldering mess after all.

good luck,

What a relief finally mate,
How many dollars did it set you back ?? and any pics of it yet??

DEZ wrote:sounds like a plan can i ask where you got your thermo and gasket from like a repco or a nissan parts dealer. what prices you get

thanx dez

Gasket was $4 and thermostat was $32 from memory.

Not an expensive excerise to buy genuine at all. And as I said, the genuine gasket is metal composite and the genuine nissan thermo is probably your best bet for maximum flow when its fully open.

Crazy to go with anything else.

yep sounds good where you get them from repco or nissan parts dealer???

dez

Genuine nissan. I went to a dealer.

IMO, don't bother with aftermarket gear.

purplebus wrote:gday guys. finally got my desert cooler rad. massive aluminium 4 core etc etc. guess what it has solved the problem. couldnt get it to run over 93 degrees (on 2 a/mkt guages)with a trailer full of tools, gerni, etc up the steepest hill i could find in the middle of the day.

she will be at the all terrain and not a smoldering mess after all.

good luck,

I'll be fitting my new brass/copper triple bypass 4 row Aussie Desert Cooler rad to my 4.2TB next weekend. Hopefully I get the same result!

will post a pic as soon as possible. got the 4 core alloy rad for $850. just spent an hour hosing mud out of it. was 3/4 clogged of mud and ran at 90 degrees up the highway at 3pm with ac cond and intercooler fully clogged.

yeeeehaaaaaa..!!!!!!

GQ4B wrote:

purplebus wrote:gday guys. finally got my desert cooler rad. massive aluminium 4 core etc etc. guess what it has solved the problem. couldnt get it to run over 93 degrees (on 2 a/mkt guages)with a trailer full of tools, gerni, etc up the steepest hill i could find in the middle of the day.

she will be at the all terrain and not a smoldering mess after all.

good luck,

I'll be fitting my new brass/copper triple bypass 4 row Aussie Desert Cooler rad to my 4.2TB next weekend. Hopefully I get the same result!

How much did your brass/copper radiator set you back?

Well I've had mixed results....

Trimmed the 2" from the bottom of the bottom hose and this smoothed out th bend nicely.

'Adjusted' the thermostat that came out of it and checked the results on the stove.
Seemed to me that it started opening at the same temp but didn't open as far.

So I fitted the new one I got. Not genuine. 76.5 deg same as the other one.

Now it runs at 1/3 not 1/4 like it did.
On heavy running the temp did come up but barely.
Still a large fraction under half rather than just on or over.
I'll attribute this to slightly better flow thru th bottom hose.


I'll still be hunting for a 90deg thermostat.

MKPatrolGuy wrote:

GQ4B wrote:

purplebus wrote:gday guys. finally got my desert cooler rad. massive aluminium 4 core etc etc. guess what it has solved the problem. couldnt get it to run over 93 degrees (on 2 a/mkt guages)with a trailer full of tools, gerni, etc up the steepest hill i could find in the middle of the day.

she will be at the all terrain and not a smoldering mess after all.

good luck,

I'll be fitting my new brass/copper triple bypass 4 row Aussie Desert Cooler rad to my 4.2TB next weekend. Hopefully I get the same result!

How much did your brass/copper radiator set you back?

$693 (inc $30 freight) - bolts straight in. The 3 row is about $50 cheaper or something like that.

Just make sure you're really specific if ordering one for a diesel or petrol as they sent me a diesel one by mistake which is hopeless as the inlet and outlets are on opposite sides of the tanks to a petrol one!

dirtyGQ wrote:red devil radiators at capalaba,$350 including gst was a NATRAD radiator exact same radiator as standard.

Whatever you do, do not get a Natrad radiator, their cores are sh!t. Here's a pic of mine that I replaced about a month ago. This radiator is only 3 years old!

I was told the same thing, funnily enough, not only by a Natrad Stockist, but many other people also.

finially got around to changeing my thermostat today (running to cool) followed yoms experience and result is exactly the same haha, still sits at its usual spot 1/3 on the gauge i didnt change it at all just out the box and in. any ideas

dez