How to Stretch life of an old D40

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Bloody hell the ebay seller has jacked the price up of the intercoolers by 100 bucks since my post 3 days ago

It appears to be as a result of the communications exchange occuring from this thread...

I'm removing the link. I really don't like sellers who do that.
 
That's a bit rough... Fair call really, he deserves to lose a but of business through here if he wants to act like that...
 
here in sa in summer the bugs seem to be made of superglue and asbestos fibres, sticky and impossible to budge

We're in SA at the moment, slowly making our way down the Stuart Highway. Haven't seen much more than pesky little flies at the moment, but we've had thousands of those since we crossed into Queensland a couple of weeks ago.
 
I think because it's been so dry for so long now the bugs are thinning out..
That said i pulled a massive locust off my spottie yesterday
 
I think because it's been so dry for so long now the bugs are thinning out..
That said i pulled a massive locust off my spottie yesterday

Thats got me thinking. Is there an issue with large spotties in front of the radiator? Judging by the number of people who have them on their bull bars, suggest that it isn't a major concern, but they do block and disrupt a fair amount of airflow that would have gone into the radiator/intercooler.
 
Spotlights definitely reduce airflow through the intercooler/radiator
Its only really noticed on a hot day, towing or sand driving or climbing a big hill, which is obviously when things are going to overheat

I compensated by replacing my fan clutch, and adding extra silicone oil to the reservoir in the new fan clutch, which makes the fan drive at a cooler temperature

Makes a huge difference to engine temps, uses a lil bit more fuel though of course
 
Spotlights definitely reduce airflow through the intercooler/radiator
Its only really noticed on a hot day, towing or sand driving or climbing a big hill, which is obviously when things are going to overheat

If I'm setting up my tourer for desert conditions, then putting spotties on the front might not be a good idea. I think I'll just make do with lights on the roof rack or maybe put a smaller lightbar on the front.

I compensated by replacing my fan clutch, and adding extra silicone oil to the reservoir in the new fan clutch, which makes the fan drive at a cooler temperature

Is that a clutch that makes the fan run faster than stock or more often?
 
From the factory they have a thermal clutch setup on them. I believe the factory unit is sealed, but Toyota sell the viscous fluid (maybe other places too) and I believe aftermarket fan hubs can be unbolted and split apart so you can add more fluid.

As for the lights, there are some pretty decent single row light Bars that would be ok on a roof rack without being too high. It really depends on what sort of travelling you do at night time, highway or off road. A light bar on the roof tends to have a lot more spread than a small one on the front. The only downside is reflection from aerials on the bull bar and possibly light in the top of the windscreen or off the side mirrors depending on where it is mounted....
 
This is the stuff

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com.au/ulk/itm/141853422998

I put two extra little bottles of the silicone oil into an aftermarket Dayco fan clutch before installing it

Adding extra silicone oil makes the fan start to drive at a cooler temp, so it comes on earlier as the engine warms up, and drives harder as the engine gets hot

Fan clutches work via a thermo spring, a spring made of two metals that moves as it heats and allows more oil through a valve, which causes more force to be transferred through the clutch

Have a look on youtube its worth understanding it


People get excited about electric thermofans and bigger radiators, but making the main fan drive harder makes a shiteload more air move through all your coolers up front

The trade-off of course is the vehicle uses a small amount more fuel to drive the fan extra hard

Old cars like the Datsuns i had dont have a clutch on the engine fan, the fan is bolted straight onto the crank and drives flat out all the time so they almost never get hot
But once again they used a little more fuel because the fan is driving so hard
 
I put two extra little bottles of the silicone oil into an aftermarket Dayco fan clutch before installing it

Thanks Czechmate for the tip.

Any reasoning for using 1 bottle over 2 bottles or was this your trial and error?

Am I able to do this with a stock fan clutch? I'm told that its sealed?
 
Thanks Ericcs

I've opened my fan clutch (also called a viscous hub) and poured more silicone oil in it. Works a treat.

Was this easy?

Also Tony, did you get a specific D40 transmission cooler kit for your D40?

I'm looking at a davies craig cooler and wondering if there is a kit with the vehicle specific mounting brakets?

The reason I'm looking at this is that I may as well fit one before I fit a bullbar and under body protection on.
 
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Thanks Ericcs



Was this easy?

Also Tony, did you get a specific D40 transmission cooler kit for your D40?

I'm looking at a davies craig cooler and wondering if there is a kit with the vehicle specific mounting brakets?

The reason I'm looking at this is that I may as well fit one before I fit a bullbar and under body protection on.

It was easy, I used a large Philips drive bit in an impact driver to undo the screws that hold it together. Just lift the front away, pour the oil in and put the front back on. Obviously try not to damage the screws, and definitely make sure you don't put anything (like a screwdriver) between the halves - you don't want to damage the face, or it could end up leaking.

I didn't get a specific kit, I just asked for a large one. It could well be a Davis Craig unit - I didn't purchase it myself, I just asked the mechanic to do it.
 
The STX already has another external trans cooler in addition to the one in the radiator. So by adding the big Davies craig oil cooler you've actually got 2 external coolers then

i did realise you lose the warmup and the equalising factor when you no longer have the auto trans fluid running through the radiator, but as it never really gets below 0 degrees here i wasnt too worried
The trans fluid definitely doesnt get too hot with this arrangement , i did some sandy beach driving on a 40+ degree day, and had a suss of the fluid and it wasnt too hot at all

Czechmate, did you get the 300x300 davies craig cooler? and is there room to fit the 10inch fan? I think all up DC say it will be 70mm thick with the fan, but I know that the engine bay is really tight.

Also isn't ATF got a bit of anti freeze in it anyway?
 
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Just an update guys. Got my Timing chain upgraded to the duplex, so no more babying this vehicle. My D40 is alot more fun to drive now.

Also got the EGR delete and it does seem to be a little more zippier.

I was told that at 130K Navara's don't really have that much carbon in the system and that a clean wasn't necessary. Any truth to this? They say that with the EGR delete and a catch can, the intercooler et al should clean itself. hmmm???

Anyway, thanks everyone for all the advice. I will keep everyone updated as my build continues.
 
The intercooler might slowly clean itself, but doing it isn't all that difficult. You'll use about 200ml of unleaded petrol to get the job done and it'll be much better straight away.
 
Thanks guys

So I just weighted my D40 at a weightbridge yesterday and I was just stumped. My vehicle weighted 2.42t. The kerb weight is suppose to be 1.985t so it didn't make sense.

My weight and daughter came to 130KG.
My vehicle has no bullbar or winch yet.
Its pretty much stock except for
Toolbox 20kg
roof rack 25kg
Lightbar 5kg
Fuel about 20L
New timing chain
say 30kg of cargo

That leaves about approx 200kg unaccounted for.

So where is all the weight coming from or is the specified kerb weight for a 2007 STX way of the mark?
 
If memory serves, they used to measure the car's weight with one sample and assumed that because they're production line vehicles, each other car would weigh similarly.

I suspect that manufacturers may have cheated with some vehicles, in order to make them appear to have more capacity than they do.

You might also have some additional weight in your chassis, which is hollow - and might have all sorts of debris in it. There are holes in the chassis near the rear wheels, stick an inspection cam in and take a peek. Underboy protection also weighs, sometimes significantly - does yours have any?
 

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