PRESSURISED RADIATOR

[Kelvin Warburton]

I have just had the 4.2 diesel in my '88 Nissan Wgn. Rebuilt (new liners, pistons, rings, bearings ,etc etc). I put the new head on at home with new gaskets and head bolts taking every care tp seat it properly. Now the motor right from start-up is pressurising the radiator (not badly but enough that it will push the water out if i give the motor a bit of a push up a hill etc. I am certain it is faulty new gasket or a pin hole in the new head. Looking for confirmation please. Or the truth.

[manno74]

I'm not sure of the name of the tool, but there is a unit which attaches to your radiator cap mount that has crystals in it that will change coulour if you have engine gas in your coolant system. Usually indicating the head gasket problem / pin holes that you mentioned. Try a radiator place or a friendly mechanic for a "test" to confirn/debunk.

The only other thing is a kinked hose (even a small one) can screw it all up and not let the system equalise, but if you've just rebuilt the motor and installed with due care, this shouldn't be your cause. On my GU a small kinked hose going to over flow bottle (moved it out of the way to mount shower hose and overlooked it when finishing off job!) caused a suction problem rather than over pressure.

Good luck.

[turps]

Maybe broken thermosatat. Main broke and then it would not take water at alll. Would just pressureise and squirt water out and over heat.

[Brunsy]

Gday my hands are still filthy from putting a new head on my GQ this arvo. The best way to rule out the nasty problems is to do what I did. Get hold of some of that sealing stuff from repco or bursons, its like alluminium filings and comes in like a small narrow container. It doesnt clog anything in the cooling system, but if your problems stop you know there is a problem with your head gasket or head.
This stuff is great believe it or not, wouldnt use it for a long term remedy but have seen it used in bulldozers and hard-worked machinery for extensive periods. My radiator was loosing water and this stuff sealed up a seven inch crack in my head. Give it a try you have nothing to loose.
cheers Brunsy

[pongo]

Gday my hands are still filthy from putting a new head on my GQ this arvo. The best way to rule out the nasty problems is to do what I did. Get hold of some of that sealing stuff from repco or bursons, its like alluminium filings and comes in like a small narrow container. It doesnt clog anything in the cooling system, but if your problems stop you know there is a problem with your head gasket or head.
This stuff is great believe it or not, wouldnt use it for a long term remedy but have seen it used in bulldozers and hard-worked machinery for extensive periods. My radiator was loosing water and this stuff sealed up a seven inch crack in my head. Give it a try you have nothing to loose.
cheers Brunsy

i CAN AGREE WITH THIS. I had a squirting leak in an alloy housing. watched it seal up and 2 years later is all good

Cheers

[marin]

can you get the name of this stuff? sounds useful to have in the car toolbox

marin

[pongo]

its called metallic seal-up . made by Car-go. u can get it from super cheap

cheers