need quick help, blown head gasket??

[TRD184]

need some quick help wqith my mates st162, we think it has a blown head gasket, car overheated, we pulled up, no oil/coolant gunk in sump or radiator, but can feel alot of blow by out the dipstick hole and when we started it with the radiator cap off and cranked it, the water pulsed out. if anyone oculd confirm this for me it would be good
cheers
james

[neal]

water will come out of radiator if you take the cap off while it is running "obviously when its cold".
Is the engine running ruff/smooth?.
Is the thermostat OK?
Is the radiator been flushed/cleaned, being a ST162 she is getting old?
Does the car overheat at idle,normal driving or both?

[TRD184]

ive never had water come out of the radiator at me when the car is cold and running :S not like this anyway. it seemed like the compression was leaking into the water jackets and forcing the water in out, is that possible?
i dont know about the running ruff, id have to ask him.
she is getting quite long in the tooth, i think its over 200,000 now. unsure
not sure about when, we couldnt get it to start once it had overheated, but he was driving it when it overheated.thanks for helping us figure it out
-James

[pandaah]

yes it is possible.. best test is a cylinder leakage test it will tell you straight away my friend and its 100% better than those pissy tk tests... or if its a backyard job, put the cylinder your testing on TDC on the compression stroke so both valves are closed and NOT on the rock, and pump air into the cylinder and see if it will hold for a couple minutes or so...

on an old motor like that you should at least be able to pump the cylinder to at least 135psi .. and see how you go... tho it is better with the engine hot so the rings seal properly against the cylinder

[TRD184]

thanks mate, will give it go tomorrow, i wouldnt bother with the tk tests either...hadnt even tohught of pumping air into it hopefully im wrong and its some really easy cheap fix....yeah right
thanks pandaah and neal

[pandaah]

yeh when you pump air into the cylinder with the valves closed, itll be good to have the radiator full and the cap off, if the pressure is going down and bubbles are coming out of the radiator then... well the rest is obvious =P

[roadkill]

hI,

if it's pushing air into the water jacket it'll either be a blown headgasket or a cracked head...........

bEn