Prado 90 T/D Overheating

[Salties Lurker Find all posts View Profile Close Salties]

Hello All,

Just wondering if any 90 T/D have experienced what I am at the moment.
When towing my Jayco Camper up hills, more so when the weather is hot the temperature gauge is going through the roof. Have already had spent a small fortune at my mechanic who has serviced the car from new. He has had the radiatior checked, replaced thermostat, oiled the fan, replaced hoses, checked co2 in the water (checking for cracked head), cleaned the dirty air con condenser. the only thing I can think now is maybe the water pump or the fan is faulty, crack in the head has not been detected or maybe the Auto transmission is getting hot causing the problem when under load. It is going in for 200k service tomorrow and to try and rectify this problem. I have also a DP chip that I was wondering if this was adding to the problem but have illimanted this as whilst the Prado was getting so hot I removed this as it is in my glove box and very easy to remove and made no difference. The car runs perfectly normal when not towing. Any information frome some one who has had a simular experience would be appreciated. Thanks.

[craig Member Find all posts View Profile Close craig]

You may need to fit a transmisson cooler, this should take some of the heat from the geabox, which should help the engine temp.

[Salties Lurker Find all posts View Profile Close Salties]

yeh craig,

This is one of my thoughts as well that I will discuss with my mechanic. The only thing still is why is it doing this now, have certainly added a number of items to the prado but these items have been on for a long time and I had travelled up to the gulf via tanimi rd and Kimberley etc in June last year and had no temp borblems then (Thank God) and I havent alterd anything since then. Maybe the transmission may have something wrong with it as well might be slightly slipping or something causing it to overheat. Don't no, worst thing is that you can only check it when off on a trip towing when it is hot.

[craig Member Find all posts View Profile Close craig]

Salties
With your trip to the gulf were you towing?
Also you say your mechanic has check the radiator, have you got full flow through the radaitor? if it is internally blocked this could also be the problem.
I don't know if the 90 series comes out with a transmisson cooler or not, I know the 120 series does. If it does make sure the fins are clean and not caked up with mud.
I fitted a cooler to 1 of my old cars it only cost about $200 and it clipped on to the radiator.

[Salties Lurker Find all posts View Profile Close Salties]

Craig,

Yes I was towing up to the gulf therfore Im sure there is a problem, the mechanic had cleaned I thought the air cond condenser in front of the radiator, im not 100% sure if the 90 has a cooler I will have to have a closer look. The radiator was removed and sent off to a radiator specialast and was all ok.

[Roktruk Junior Member Find all posts View Profile Close Roktruk]

Did your mechanic check the thermostat before it was fitted? These things have a notorious failure rate from new - it always pays to chuck them in a pot and bring it to the boil to make sure it is actually opening.

Always check the most obvious first.

Next is the fan clutch, start the motor cold and hold the fan stationary, as the motor heats up the viscous fluid will heat as well and make it harder to stop the fan turning. no resistance means the fan isn't engaging as the motor heats up and probably isn't operating effectively.

Is the transmission fluid burnt at all? Excess heat caused by transmission slip can be transferred through the cooler ( in the bottom of the radiator) and cause the engine temp to climb. Early GQ Patrols suffer this problem.

Is it losing water at all? No external leaks (picked up with a pressure test of the whole system) may indicate an internal problem. Hardest to pick is a leak into the exhaust side - it disappears into steam. Easiest is a head gasket blown into a cylinder. Bubbles in the radiator (or blowing hard out of the cap!) is a dead giveaway.

[Roktruk Junior Member Find all posts View Profile Close Roktruk]

WELL......$3700 later, my overheating problem is solved. New Head - cracked through in no 3 pre combustion chamber. It started to run rough, then got very hot, very quick. Fortunately it was still in the 3 month dealer warranty (by a week!!) and Toyota paid with little argument.

I suspect that there's enough of this problem occuring to have a case against them for a warranty claim. I think they'd rather do a case by case than a total recall!!

Greg

[Dieselman Member Find all posts View Profile Close Dieselman]

Hey Salties,
Can you hear the fan coming in and out while driving? I have a set of Hella 4000s on a standard alloy bullbar which blocks off a lot of airflow and when pushing it on a real hot day(35c+) i can hear the fan lock in and out. Also if pulling up for an intersection and then taking off again the fan will mostly be locked in for a 30sec to 1min and then unlock. Hope this helps Ben