306 diesel pressure build up

[andysautos]

hi, can some one please help me.
i have a 1995 n pug 306 diesel non turbo, it builds pressure in the cooling system and blows overflow and loses all water, also if you start car with rad cap off water shhots to top and overflows..
i have replaced.
thermostat
head gasket
hoses
rad and rad cap
cylinder head has been pressure tested, skimmed and is all ok, but the problem still there...

[bad driver]

I have exactly the same on my TD, wish I knew the answer.

[Dave Burns]

Just because its been skimmed doesn't necessarily mean its any better than it was, the job needs the best machinery and a keyed in operator if its going to be successful.
If you can start the cold engine and have it push water out the rad straight away, then thats combustion gasses doing that and for them to get out in such quantity almost certainly means the head gasket.
Heads can crack but usualy this shows up worst when hot.
Dave

[Peter D]

Remove the head and try and locate the staining which shows the leak up. Check the surface of the block and any signs of raised areas around the treaded hole due to pulling. If all thus does not reveal the problem then get the head pressure checked. and be prepared to source a replacement head. Regards Peter

[bad driver]

Ah well, found my problem mainly due to the sudden big cloud chasing me down the road today!! head went pop!!!
Anyway stripped it down and the staining shows evidence of gas leak between chamber one and the far corner port for the coolant! Seems to of gradually crept over and today made its way to the oil as well.
Lucky me though, I have a spare cylinder head of another engine which I know to be spot on so on with the rebuild.

[philhoward]

At least you've found the problem; shame it's the head, but the symptoms suggested a very bad combustion leak.
Best get your spare head checked, just incase it's got upcoming problems; they may be able to be sorted now rather than later.