Extra cooling

Hello,

I've got a 1993 Cruising cabin and plan to take it into some rather hot places so I thought I could add an extra fan in the space behind the front bumper and radiator grill to blast the radiator if necessary. I figured I could put one in and switch it on from the cab if things were getting heated outside, nothing fancy, no sensors, just a manually operated fan. But when I had a look there's something else there.. And another fan, so I've got a few questions about the whole thing..

Does the engine fan suck air from outside through the radiator towards the engine or the other way around ? Sorry but I don't fancy putting my hand in there to find out.

What is the big thing about the size of my radiator that looks like a metal box with ribs lying face down with a fan on top of it that is in front of the radiator ? It almost looks like somebody pushed the normal radiator over and it's just lying where it landed with the fan pointing towards the ground. I can't find it on the exploded diagram from Mega Zip.

Has anybody had any success or has any tips regarding adding another fan ?

Thank you.

Hello NickZ

First of all these vans are fairly common in Oz, the Philippines, Thailand, India etc so don’t think they can’t function in generally hot countries, but nevertheless cooling is important and often neglected.

There are also lots of posts on here on cooling (more later), but see below your very post for a start; annoyingly these aren’t ‘picked’ until you post is made, I think. Some are poss useful some poss aren’t, too.

The cooling system is very well described in the EPC, but quite a lot of it is in the electrical sections. Look there for the AC. There are also a few different options for the AC for the front (horizontal area) sandwich. I think some of these are destination-country related but once you can compare your setup to the options within the EPC you’ll be better placed to know what’s what.

Cooling is a very, very common topic on here and the cooling system on my van, despite some service records, had been somewhat neglected. I’ve done and am continuing to do a lot of work in this area and I wrote a very detailed post in my show us yours section as I’d previously put snippets elsewhere and wanted a single place to put everything. Have a read and it’ll hopefully answer almost all of your questions, plus a load you don’t ask, but probably should

I don’t mention there that the clutch fan does draw air in the direction front to back. There are lots of steps you can, or could, take to increase total cooling and cooling efficiency (see my post) before adding additional fans, which would be push fans btw. Some have done this but I’d start by thinking of all the ways to improve total cooling efficiency first. Putting additional fans in the line of airflow might possibly restrict airflow and lower efficiency with its consequences.

In my post I also mention auto transmission cooling and the qualitative impact this seemingly has on the heat budget of the vehicle. While I have no numbers, autos have a different cooling system, which I’d change to an ATF to air cooler rather than dumping this heat in the lower radiator.

Also look at the options implemented on turbos.

Cheers!

During Oz summers with temperatures sometimes up around 40C, I have experienced no problems, other than when the radiator became partially blocked. If you are towing something or have extended hill climbs keep an eye on it, but otherwise as long as the cooling system is in good condition I don't think you need to make any changes.

The fan on the horizontal radiator appears to be thermostat controlled. Before I had the radiator replaced it could be felt kicking in on a long hill climb. I haven't noticed it doing that since the replacement. While I guess there could be an issue with the fan I think getting the correct cooling from the main radiator has decreased the need for the second fan.

Thank you both for the replies, I will investigate the posts and see how my automatic box cools. I was more concerned about overheating in traffic in hot places with no air flow through the grill but I also plan to go up some mountains and into jungles so that's hard work on the engine. This won't be until the summer at the earliest so I can give it a test here in the UK on a hot day and see what happens.

My camper's already got an engine monitor gadget with an accurate temp readout in degrees and this was fitted along with a new cylinder head so something went wrong and I don't think the normal gauge was deemed to be trustworthy. The next ( last ) owner had the radiator rebuilt recently and the whole system cleaned out, then he got caught out by low emission zones and had to sell, I think I would've moved, these vans are awesome ! I'll also be replacing the water pump when the cam belt is done.

It was just a thought and I'm pleased to hear that these vans can handle the heat so long as you're careful, thank you.

That horizontal radiator is a secondary radiator plumbing in piggy-back to the main radiator. The solid plate with louvres is sheilding from debris & knocks. The fan is switched both for the AC and also thermostatically on engine coolant temp (I don’t recall which of the temp sensors is specific to that fan).
At high temps or after switching van off after a hill climb that fan when operating correctly will actually run while the ignition is switched off.

In response to how the auto box cools, the primary radiator (vertical in front of engine) has a transmission fluid heat exchanger built into it. From underneath you should be able to see the transmission fluid lines going in and out at the base of it.

If you don’t know the history of it, a worthwhile job is to replace the fluid in the radiator fan clutch. Silicon oil. There is a great YouTube video howto for a Toyota Landcruiser (I think). You can buy the fluid from Toyota but it seems the amount they supply in the pack/kit is inadequate. I think they supply 18ml when (from memory) general consensus is 30ml. Exact same silicon fluid is available online or from parts shops. Lots of related info on the 4WD Landcruiser/Hilux/Surf forums.

Pete_nz... Thanks for the information, that's solved some of the mystery and I'm going to have to keep a check on my fans to see how / when they start working. I'll also look into the radiator fan clutch thing as I want it all as good as it can be.

Pete_nz wrote:

In response to how the auto box cools, the primary radiator (vertical in front of engine) has a transmission fluid heat exchanger built into it. From underneath you should be able to see the transmission fluid lines going in and out at the base of it.

Thanks for this. I think I mistakenly wrote that autos might cool into the flat radiator.

Pete_nz wrote:

If you don’t know the history of it, a worthwhile job is to replace the fluid in the radiator fan clutch. Silicon oil.  There is a great YouTube video howto for a Toyota Landcruiser (I think). You can buy the fluid from Toyota but it seems the amount they supply in the pack/kit is inadequate. I think they supply 18ml when (from memory) general consensus is 30ml.  Exact same silicon fluid is available online or from parts shops. Lots of related info on the 4WD Landcruiser/Hilux/Surf forums.

Yes, absolutely!

NickZ see my long post in my show us yours section on cooling. I describe one of the main failure modes of the fan clutch there. Timmy the Toolman (YT) has a great vid going into this, plus there are several others great ones out there. The fan cluct is a very common topic of conversation and is also used on lots of vehicles.

The best price I could find for the oil was about half the price of a new OEM (AISIN) unit so I opted to replace mine. I was also a bit suspicious of the spring / bi-metalic strip part.

Thanks, I will investigate Timmy the Toolman, that sounds like expensive oil !

NickZ wrote:

Thanks, I will investigate Timmy the Toolman, that sounds like expensive oil !

NZ$19 for 50ml in large syringe from one local parts supplier BNT.

LH119V wrote:

Thanks for this. I think I mistakenly wrote that autos might cool into the flat radiator.

I got it slightly wrong from memory. Both trans lines run into the RHS of the primary rad - one at the top.

https://silverdaleradiators.co.nz/products/toyota-hiace-super-custom-diesel-auto-1991-1996-radiator-new?variant=39950980219051

LH119V wrote:

The best price I could find for the oil was about half the price of a new OEM (AISIN) unit so I opted to replace mine. I was also a bit suspicious of the spring / bi-metalic strip part.

I had a look at my fan clutch and did the Timmy the Toolman tests, it works but not as well as it should so I think I might as well replace it but I can't get my chassis number recognised on any website because it's an import and the model types don't match mine either. The only thing that I can identify with is the 3L engine part.

Also I can't find the fan clutch on the mega zip exploded diagram to get the number so have you got any suggestions on how I go about making sure I get the right one or do you have the original part number ?

I've found the AISIN clutch at about £100 but want to be sure it's the right one.

Thank you.

Hi.

On the EPC (as previously mentioned and I generally find this better than MegaZip and a bit cheaper) the fan clutch is on the water pump page within the engine section. Simples

You can cross-check this against Autodoc, but I think they don’t list the Hiace properly based on model years and engine types (‘cos import and 90s?). Another problem is that it’s very common for OEM part numbers to have seemingly changed over the years. I couldn’t find a Toyota part number on my old fan clutch, either.

I don’t know the difference between each and every type of seemingly very similar fan clutch. I expect they all operate along slightly different performance curves but I really don’t know.

Now you know where to get the part number see what you can find? I’m not going to tell you to get one part over another. There’s also a huge price variation on Autodoc for your troubles and I’ve faced exactly the same problem with lots of parts purchasing. Then there’s stock availability.

Finally don’t forget the invaluable assistance available from a good motor factor. They generally carry a ranges across several parts companies so some might not hold AISIN or RIDEX, but do SACKS and Blue Spot. Good motor factors will go the extra mile for you. Also don’t forget your local Toyota dealership. They have also been very helpful for me. The internet does not always have the best or only answer, but it's useful as a first step

HTH

Ok thanks I've now found it on the Megazip page it's a 16210.. I will investigate.

Hey Nick.

If you have the blue clutch, very likely, it’s an Aisin FCT-004. It’s on an absolute ton of 1990 Toyota trucks/SUV’s.

Good luck, God Bless
-Bryan

Thanks Bryan, I will check my dirty looking fan.