Thread: Overheating Again!!! I'm over it!

Originally Posted by LandyAndy

Im not doubting your skills but its possible to fit a thermostat back to front,assuming its one you can simply replace,unless its like a D2 where its encased in the plastic hose union.
If its a free thermostat that you can simply replace(old school),drill a 6mm hole in its face plate,it eliminates air pockets that prevent it opening,especially if a leaky head gasket is introducing "air" into the coolant.
If it has the said D2 style thermostat,this advice is useless.
GOODLUCK
Andrew

Nah its a seperate thermo, outside the engine tucked behind the radiator. I did wonder that, but the hoses wont allow you to put it on the wrong way.

Originally Posted by daf11e

Redandy another check is to see if the hose from the radiator to the coolant tank is hot ( the thin one) if that's cold and the car heats either blockage or air.

I did check that and seems tempramental. It would be cool one moment, then quickly heat up.

It does sound to me the water pump.

Can air pockets potentially deztroy water pumps?

If it's cool sometimes could have grime inside building up at times.....it'd pay to blow through it...I'd remove it at the coolant end as the radiator end is brittle and can break...you don't need another rad...doubt an airlock would wreck your pump that is I have not heard of it.

Hi redandy,
If you top the system up to a normal level and start the engine with the rad cap off if you get constant bubbling up through the coolant this would be an indicator for the head gasket, another check would be a compression test, all plugs out, foot to the boards spin the engine and record all the compression test results. Look for a duff cylinder or anything suspicious, pressure should be between 150 and 175 psi I think.
Thermostat in hot water with thermometer and check function of the thermostat.
Collapsed hose internal, delamination of the hose.

Maybe try some of that lot.

A word of warning: Don't just remove the plugs etc. you need to remove specific fuses so that the ignition system is not energised. My understanding is that you can cause damage to the ECU letting the high tension leads fire off with no load..

One other thing which can cause overheating is a partially blocked exhaust system either a failed baffle in the muffler or some other obstruction. This is usually indicated by a gradual heating up of the engine during operation, you can check by having some one rev the engine up to about 2,000RPM whilst being at the end of the exhaust and listen for a hissing sound as the air is being forced out past the restriction or taking one of the thermo couples out and connect a manometer up to the exhaust to check pressure.

Gippy been caught before way back with an FC Holden.

Originally Posted by Hoges

A word of warning: Don't just remove the plugs etc. you need to remove specific fuses so that the ignition system is not energised. My understanding is that you can cause damage to the ECU letting the high tension leads fire off with no load..

Hoges

You beat me to it!

Do not turn the engine over with the plugs disconnected, unless you want to replace your plug packs as well

Steve

Hi Hoges / Steve,
Thank you, forgot to mention that important little detail....