300tdi over pressurising

Hello to you all hope someone can help with this, I have a 1995 disco 300tdi which is overpressurising ans sending water out of the expasion tank.

I have fitted a new radiator (cos mine was leaking ) new thermostat there are no visible water leaks, no water in the oil,no increased sump pressure and nothing coming out of exhaust. I have check all the hoses and nothing appears to be blocked, i can poor water through the heater with the pipes off no problem but if I remove the return pipe from the heater with the engine running theres no water comming out. I i blow down the expansion tank water comes out of filler on top of thermostat housing and through outlet on top of cylinder head that goes to heater so cant see how anything can be blocked, at moment running it with thermostat removed but still getting too preasurrised.
Does anyone have a clue what to try next (apart from semtex)

sniff test.......... now go n introduce yoself

what the hells a sniff test

scash said:

what the hells a sniff test

Click to expand...

Test for exhaust gases in the coolant..........most garages are kitted up for it

and.............now introduce yoursef.

Never tried Semtex on a head gasket

theres C4 in the Freelander headgasket, or was that just mine

Freelander ones are made with marshmallows!

Generally if the cooling system is pressurised then the head gasket has gone.

If the water pulses out of the expansion tank when the engine is running then the head gasket is proper fooked because as the piston rises it forces pressure into the system and forces the water out.

Forget about trying to pretend it's not the gasket.

Funkykipper said:

Generally if the cooling system is pressurised then the head gasket has gone.

If the water pulses out of the expansion tank when the engine is running then the head gasket is proper fooked because as the piston rises it forces pressure into the system and forces the water out.

Forget about trying to pretend it's not the gasket.

Click to expand...

What's wrong with burying your head in the sand?

I'm afraid I agree sounds like head gasket

well thanks to all who replied flushed the system today and refilled it but still doing the same and I can get water all throught egine block and new radiator so looks like your right will take the head off tomorrow after work what joy thanks again for the help.

There's 2 small bore pipes one from stat housing other from top of rad going to a t piece then to header tank. Make sure they aren't blocked, particularly the t piece, this can cause air locks, chucking coolant out and head gasket failure! Paticularly if it's had rad weld or similar in it

i agree sounds like the head gasket or a cracked head.