Hilux 4x4 Forum

Hi guy's. Have a overheating problem with my 2.4 surf. Have replaced the head, has new radiator waterpump viscous fan. Round town runs perfect but any load on the engine cause's the temp up. Have even taken the thermostat out so should run cold. Only thing I have not re connected is the air con pump. Can anyone help or think of something I have missed.
Pete

Peter
Did you clean you radiator properly,did you use Toyota antifreeze and last thing did you replace your radiator cab with original Toyota one?

You've looked at all the obvious stuff that covers cooling, so now you have to look at excessive heat generating factors like incorrect fuelling. Have you cleaned the MAF sensor, checked diesel pump, filters (fuel and air) and injectors?

Yes correct fuel and changed the rad cap. Will have a look at the maf sensor and diesel pump. coolant and rad cap are otp's

Might be, and I sure hope its not the case, that you have a crack in the head you have put on.

Even though it might have been pressure tested, the head need to be heated to operating temperature and only then tested.

This happened to me previously, and believe you me we struggled to find the crack.. It tested perfectly when cold. My car would drive with the heat gauge almost stuck at a certain level, and then all of a sudden the temperature would climb fast and very high when going up a hill.

Hope you get to the bottom of this...

How sure are you that its really overheating, may just be the gauge having a problem or does it start spewing steam?

Bosfebok wrote:Might be, and I sure hope its not the case, that you have a crack in the head you have put on.

Even though it might have been pressure tested, the head need to be heated to operating temperature and only then tested.

This happened to me previously, and believe you me we struggled to find the crack.. It tested perfectly when cold. My car would drive with the heat gauge almost stuck at a certain level, and then all of a sudden the temperature would climb fast and very high when going up a hill.

Hope you get to the bottom of this...

Know nothing is guaranteed but it is a brand new head

Knuppel wrote:How sure are you that its really overheating, may just be the gauge having a problem or does it start spewing steam?

bypassed the original temp gauge with a dash mounted one. Doesn't spew steam. Only overheats when going up hill when the engine's under load. Will happily sit at just below halfway whilst pottering round town or on the flat

Here is another wild thought for you.

Is the radiator new or refurbished?

Had a case once when a cruiser kept overheating after it broke the fan belt. No matter what you did it started to get hot when it saw a hill. Eventually we removed the radiator again, after it was sent for cleaning and checking, and saw that the tubes inside had expanded to such an extent that they block the airflow through part of the radiator. We re-cored the radiator and then problem solved.

What happened was when the v-belt snapped the engine overheated and the release on the radiator cap could not vent the steam fast enough and it then popped the normally oval tubes into round tubes. Not very obvious unless you do a personal inspection looking for that specific problem!

Brand new rad as were all the parts I have replaced