Thread: Coolant Pressure in my Defender Tdi300 - How to diagnose Head or Gasket?

Originally Posted by Tins

I don't have your experience, but I agree. A quick look at the pics suggests to me that the HG was leaking between the water jacket and cyl #3.

Spot on, about 8 o'clock, number 3, 7th and 8th pic from the top, even has the compromised water jacket seal as well as the rust stain on the gasket fire ring.

Originally Posted by Robmacca

Yes, but that was because I made a mistake in the way I connected the small hoses between thermostat housing - Radiator - Overflow bottle. The mate helping me picked it up and corrected my mistake and all was good then onwards

Bit of an update...

The engine is now running fine, actually better than before... The funny thing is that after the rebuild back in 2019, I could always hear a thud-thud noise through the Snorkel when the engine was running. We went through and checked all that we could and all came back ok.
After replacing this head gasket now, that thud-thud noise through the Snorkel has completely gone and it sounds what I would call - normal. Have no idea why it would disappear after replacing the head Gasket, but it's one less noise to worry about now