Another overheating issue...

Evenin' everyone

300tdi

Got another overheating issue... getting pretty bored of it now.

The top hose is cold and system is highly pressurised. The pipes look like they are gonna explode. Getting plenty of heat into cab. Seem to have a big air problem. After another test today, just round the block to get it up to temp, it soon overheated. Though the temp gauge did not go above where it should, water started coming out of the cap and a very slight hiss coming from where the heater pipe goes into the top of the head.

I've been filling via housing etc, burping it, running it a little, topping up, filled matrix pipes just to be sure. I honestly don't think I'm doing anything wrong in that department, but as soon as I think I have all the air out, I take it for a run to bring it up to temp, and it boils over. Of course I then cant do anything for a couple of hours.

Tomorrow, I am going to check 'stat and probably replace regardless, and remove breather pipe and blast with air. This has been done recently but i'll check em again as last time that solved all my issues. Rad is new, p gasket done, waterpump new. All hoses tight. Expansion tank is fine.

I am of course now very worried that the head has gone, or at least the gasket, and the exhaust is getting into coolant. Gasket was replaced ~5k ago.

Any suggestions will be much appreciated.

Sounds like HG... any sign of exhausting through the expansion bottle when the cap is off? If its not visible, it will be worth getting a garage / someone with a test kit to test for fumes escaping through the water system.

Was the head skimmed last time the gasket was done? cost about £45 to skim them .

GSF were selling a product last week boasting about this stuff called steel seal ,head gasket fixed or your money back !

Steel Seal - Head Gasket Engine Block Repair & Fix Pour-In Liquid | eBay

Yeh head was skimmed (for a lot less than £45 ), and I'm on the 3 hole gasket so only got one more skim left in her.

I hadn't touched it since yesterdays boil over until 10 mins ago, so it's been sat for about 16 hours. As soon as I undid the expansion cap, it started squirting water out. So high air pressure still in system. Would this be a good indicator of air getting in? I am going to replace the breather pipe and stat now.

Stat seemed fine in the pot, started opening about 85c. Pipes and valve seemed clear but replaced anyway. Looks like it's head off tomorrow then.

If I do need to replace the head, and I can't believe I'm asking this.. are the britpart ones any good? There's a lot out there, all for different prices so not too sure which to go for.