Hi

What would cause over pressure in expansion tank in a ef or for it to still have pressure left overnight when you take cap off.

is putting liquid sealer that is like peter maherd liquid intelligence that doesn’t have the fibres and copper ok or will it block up stuff.

is it normal to hear something when taking cap off.

took a cap off a uncles ed and never heard a hiss like a coke bottle

so what would be reason for the ef hearing that.

Could you use the sealer that doesn’t have the fibreglass and copper and fibres without causing problems like this one, https://m.ebay.com.au/itm/112553360495? ... noapp=true

used peter mahers liquid intelligence and it never blocked anything up and this ones same only it’ll work with coolant and you don’t have to drain like the other stuff.

Also any chance it’s lpg converter putting air in, currently using petrol until lpg is fixed but wondered anyway as converters connected if that’s got anything to do with it.

Any of those things are emeegency repairs, it'll clog your radiator galleries up (that's how it works).
If you use it, follow the directions to the T!

What makes you think your headgasket has blown?
It might just be the cap is of higher pressure rating.

That one thing you're describing isn't a problem