Outer Limits 4x4 Board

got a 85 hilux with a 3y motor i'v changed the radiator to a larger radiator and water pump and put a new thermostate all new and still heating up high then normal almost to the red i'v changed the thermostate 4 times so can't say it is the thermostate

Guage could be reading wrong! Have you tried a new temp sensor

what type of driving conditions does it heat up under

it's starts heating from idle and without thermstat it reads cold

Does it have a clutch fan on it and is it working?

has a clutch fan and works fine
runs cold without thermostat only runs hot when thermostst is in
i put an 82 deg in it still goes over and replaced it with 4 diferent one still the same i've flushed it with radiator flash aswell
how do i tell if the clutch fan is not working it spins when motor is running

take it to a sparky or a radiator place. they will have the specs on the resistance for your temp sender and can tell you if the sender is kaputt. they can also tell you if the temp on the guage is the same as what is actually in the block/rad by putting a laser thermometer on it.

if your sender is fine then is it possible that you have a problem with the motor producing more heat than the rad can handle with the thermostat in? Is it diesel, coz if it's overfueling or leaking a compression via a crack or head gasket you will get extraordinary temps being produced by the motor.

get a coolant/exhaust chemical dye test done to see if there is exhaust gasses in your coolant

hope this helps

MILO

bundy4x4 wrote:has a clutch fan and works fine
runs cold without thermostat only runs hot when thermostst is in
i put an 82 deg in it still goes over and replaced it with 4 diferent one still the same i've flushed it with radiator flash aswell
how do i tell if the clutch fan is not working it spins when motor is running

My Hilux did the same thing last year.
I took it to a radiator place and he said, sounds like the radiator was blocked. Suggested I clean it out.

Got home and lifted the bonnet and noticed that the fan wasnt spinning with the revs.
I grabbed a stick and put it against the fan ( not recommended) and it stopped.
Replaced it and havnt had a problem since.

yeah sounds like the viscous fan is not up to it. As said, if you do not know how to check it get a rad shop to do it. Basically, with engine off, try and spin the fan by flicking it in one direction. It should only turn by about 1 or 2 blades. If it does not have enough resistance it needs attention. Pull it apart and top it up with viscous fluid (readily available over the parts counter at Toyota). Again, if not sure get it checked and repaired by a good rad shop.

Viscous Fan Rebuild

recently had the clutch for my engine fan fixed up. It was gettin lazy like the others and not doing its job which meant low speed high rev situations saw the temps going nuts. Apparently its a common thing for luxes.

They repack it and overoil it slightly so it works better than new. Cost $70