ATF trans cooler fitted - high temp showing with new gauges

[scubadog86]

Been searching this afternoon and not found the exact answer I am looking for. I have had fitted a ATF oil cooler and oil and water temp gauge for added piece of mind as I have a long trip around France and Italy this summer so t was recommended I get an oils cooler to help the standard one.
Now with both temp gauges fitted inside the car water temp sensor in the top rad hose and the oil cooler gauge fitted with the cooler and the gauges which are good quality around £60 each btw show 90c water temp which I think is quite high with an addition to a new cooler and the oil reads about 65-70c

My question is what should they both be showing as I have set the peak at 100c and is their a way of knowing if the cooler that has been fitted is doing its job.

I think I worried less when I couldn't see what the temperatures were reading. Kzn130

[woodwarm]

Try for eng temp http://www.toyotasurf.asn.au/forum/v...ic.php?t=14717




Try search at top of page, there is some info

[Lewd Lux Lover]

sounds like water a little high and oil a little low. Is that an average taken over quite a few miles over differing road conditions or peak or what it got to on a short drive out to see if they were working?

what shape is your viscous fan in? Have you refilled it or replaced it? Have you got an oil stat inline with the oil cooler?

You should be looking at 85 across both of them give or take from what I have researched. If your oil is circulating in the cooler all the time it might never get hot enough to evaporate contaminats (80c) and if your fan is not coupling hard at hot times then your rad cant loose the heat fast enough.

Ideally I would bring the one up and the other down.

Have you toally bypoassed the in-rad cooler or put your in series with it?

[scubadog86]

The oil cooler has been put in addition to in in rad cooler and after about a 10 mile run the temp never registered on the new temp gauge only risen when stopping at lights or going slow which I was told was fine and around town stop start it hit about 70c well I thought it was a little high as I thought with the new cooler it should be reading lower. Fan is ok
With regards to the water on motorway it sits around 88c but stop start and town driving it peaked at 91c again with a cooler I thoughyit should be aroun 80-82c if reading the oz forum

What I was thinking was to ad a fan to the cooler to bring the temp down but if u are saying t should be 80c with an added cooler then that's not an option if u are sure it should be in the 80's

[tashtego]

Make sure you have tested the viscous fan properly, do a search on here for how to check its operating ok.
Otherwise get rid of the gauges. They might spoil your trip.

[Lewd Lux Lover]

yeah just spinning it when its cold and feeling it stiff isn't going to work.

get the engine really hot and stop it. reach down and give the fan a hard push. it really should resist you hard. 5-10% slip. You can only tell if its coupling when its properly hot. If its firm when its cold it means nothing as all you are pushing against is the oil in the bearing, not the oil in the coupling as its mostly been sucked back into the reservoir.

or get the engine hot and make sure its going like the clappers. this is not so defined though.. They apparently sound like a jet engine when working fully. I just cracked mine open, took out the old goo and replaced with some stiffer oil. Yet to refit it as yet though.

I could see where all the old oil had seeped out over the years though, past the seal.

Your temps sound ok to me. A derve should run at 88c for best efficiency apparently, so the internet says.

[Lewd Lux Lover]

if you can fit a fan on your cooler show me how because I couldnt where I put mine. I have aircon rad though so space was tight.

[scubadog86]

I removed my air con system and what I would have done is use the air con fan on a switch in the dash for hills or traffic but at the minute as it looks like IT IS running cold ( according to a aid guy who messaged me ) I won't do that apparently ATF temp should be around 75 with or without a cooler mine is on the cold side and water like you said 82-88c mine is on 91c

Will try spinning the fan when the engine is hot and turned off if it spins then it's not working properly?

Cheers Lux

[shokenore]

The addition of an oil cooler to supplement the oem set up will help with engine coolant temps, but , you are better off letting the radiator cool the engine coolant and a separate oil cooler cool the ATF.

Depending on the accuracy of your sensor and gauge and how it has been installed and calibrated could give you the high(er) than expected coolant temps.

If the temp of the coolant seems ok at speed then we can assume that the rad is in good condition.
You will experience a rise in temp especially after slowing down after a high speed run.

The viscous fan does the majority of low speed cooling by pushing air over the rad this is supplemented by an electric fan, controlled by a thermo switch.


Check the fan by seeing if with a cold engine it is initially hard to turn then becoming easier this will show that there is silicone fluid in the casing.
Take the truck for a hard run to get it up to temp then let it idle for ten fifteen minutes then turn off the engine and the keep the bonnet shut for another 3 - 4 mins or so then open the bonnet and see if the fan is locked up

if not then it would be advisable to check the viscous fan it could just need the silicone fluid replacing

[tweak'e]

90c water temp is fine.

atf temp, depends on where you are measuring.
also depends on which way around you have the two coolers. best to use the new cooler but if its a bit small then have the new one inline first then the factory radiator one. thats to reduce the amount of heat going from trans into the engine cooling system.

if you think trans temp is to cool (which is not normally a problem unless it gets really cold) you can fit an inline thermostat.

[Lewd Lux Lover]

Now that is a well rounded reply. Where is the rep button?

the viscous fan is not hard to refill but as I say its not back on the car yet so I'm not sure if it went well. the actual doing of it is fine though

It defo didnt have as much in there as I put in. About 40ml of 10,000c silicone oil went into the inner bearing side which was how much it took to start feeding out of the outer ring.. parts should be back from the engineers in a week or so (getting gauge sensors fitted) and I will give you some readings to compare to.

As the last post said I would treat the readings themselves academically. Get to know the average so you know when something goes wrong. Normal readings within a degree or two of the stated norm could just be interference in the sensor or the gauge.

What gauges do you get out of interest? It might be worth doing the little mod to the OE temp gauge so you can flick your eye between them? I am looking for a guide for the 3rd gen to do the same as I am not electronically minded and dont know if its the same parts but have not found one yet.

[Bogus]

Transmission oil ( ATF ) - rolling along the road at 55mph plus you are in lock up and your ATF leaving the sump and going to the rad will be cool, In these circumstances the in rad exchanger will heat the ATF returning to the sump to 80-90 deg, If youre ATF is cool on a 10 mile run then Id have to assume you are taking the temperature on the inlet to the in rad exchanger ( and Im assuming you still use it and have not bypassed it completely.) that will be why it shows cool. In town and puddling about your box is constantly shifting, its never in lock up and the ATF will get hotter, If it gets really hot then it can add heat to your engine cooling system ( not a lot however as the in rad exchanger for the ATF is quite a wee thing.
As others have said, the best thing you can do for a Surf cooling system is to ensure that the viscous fan is at full efficiency. With that working as it should I doubt an ATF cooler helps or hinders much of anything for normal motoring, but probably does help if you are ragging your truck offroad or dragging a big trailer/caravan around.

[tweak'e]

...... In these circumstances the in rad exchanger will heat the ATF returning to the sump to 80-90 deg,.........

only if the radiator is blocked the engine almost overheating.
the bottom of the radiator is normally cold.
its certainly not going to heat it up to 90c when the water temp before the radiator is only 90c.

[Bogus]

only if the radiator is blocked the engine almost overheating.
the bottom of the radiator is normally cold.
its certainly not going to heat it up to 90c when the water temp before the radiator is only 90c.

Yes you,re right if your cooling system is good it,ll add either nothing in the way of heat or at best just a few degrees.

[Lewd Lux Lover]

A few degrees in an already marginal system under stress. Thats more than enough to account for a good many dead 1KN wouldn't you think?

I have only just bought the vehicle and the first thing I did was get shot of the in rad cooler. It will be towing and that source of extra heat into the system can only lead to bad things. Its a shame Mr Toyota didnt make more effort what with being the be all and and all of off road producers.