Overheating Issue (Boiling)

[greenacc]

Hey Everyone,

I have searched the forums, found some good suggestions but thought i would post my own thread to see what others think.

Currently, when the engine temp reaches 102 Degrees i can hear boiling in the reservoir with fans not running unless AC is on which is not ideal long term. I have replaced the Radiator, Pipes, water pump, radiator cap and Thermostat and still same

Thoughts anyone?

How rough is the metal casting where the radiator cap seals? If it's rough and pitted the system might not hold enough pressure to prevent boiling.

 

[Fu Manchu]

Hmm. Test the fan.
Easy thing to do is swap the fan with one from the wrecker. Might not sort the issue though. Parts swapping isn’t ideal.

Maybe remove the fan and see if you can get it to run by earthing and providing power to it with a makeshift circuit off a 12v battery. Not sure of how the fan is wired though.

You might also be coming back to that coolant sensor.

A tech2 device could activate the fan while in the car to test it.
It would also be able to access the coolant sensor data to see if the data is correct.

 

[sprayzz]

How rough is the metal casting where the radiator cap seals? If it's rough and pitted the system might not hold enough pressure to prevent boiling.

Would this be the cause maybe? Not smooth at all

 

[Fu Manchu]

The cap might not seal so well on that.

 

[sprayzz]

The cap might not seal so well on that.

Yeah it’s super rough and very jagged.

 

[sprayzz]

Hmm. Test the fan.
Easy thing to do is swap the fan with one from the wrecker. Might not sort the issue though. Parts swapping isn’t ideal.

Maybe remove the fan and see if you can get it to run by earthing and providing power to it with a makeshift circuit off a 12v battery. Not sure of how the fan is wired though.

You might also be coming back to that coolant sensor.

A tech2 device could activate the fan while in the car to test it.
It would also be able to access the coolant sensor data to see if the data is correct.

So i took out one fan relay one at a time with the AC on and both work fine, perhaps it’s just programmed to have only the drivers side fan going unless it fails in which case the other starts, not 100% sure.

Will change the sensor and the filler neck next week.

 

[99notout]

Would this be the cause maybe? Not smooth at all

You need a new filler neck, and make sure it is flushed and running the correct coolant. It shouldn't corrode like that with the correct percentage of coolant, the cap would not seal with that corrosion. Yep, fans kick in at 108 Degrees.

 

[sprayzz]

You need a new filler neck, and make sure it is flushed and running the correct coolant. It shouldn't corrode like that with the correct percentage of coolant, the cap would not seal with that corrosion. Yep, fans kick in at 108 Degrees.

Cheers, it didn’t look right once I cleaned it up and felt it was very jagged so thanks for that tip, I’ll replace the filler next next week, I am highly doubtful it’s the coolant temp sensor after seeing that but might replace it anyway just in case.

I assume the filler neck piece is just a simple bolt on sorta speak?

 

[99notout]

Yep, easy replace. If you get a new one from Holden it comes with the seals etc. Get the Dex-Cool while you're there, it's not too expensive.

 

[Trevor loves holden.]

Would this be the cause maybe? Not smooth at all

Click on the link I gave you, it explains your problems.