380rwkw Gtr. No 6 Cyl Full Of Coolant

[BOOSTD]

I have recently been experiencing idle issues and also hard starting after sitting when hot. Today it blew a stack of steam out the exhaust so I pressurised the radiator and pulled the plugs. Number six was full of green coolant....to the extent that when I turned the motor over to clear, it shot a stream out so hard it made a neat hole in my bonnet underlay.

What confuses me is how a trust metal head gasket could let go?? would it be more likely a crack in the head or block? I did notice some small cracks around the head stud and water jacket holes in the block after getting it bored out. Advan told me this wasn't an issue and the N1 blocks are the only ones that don't do it.

Has anyone had a similar problem with a metal head gasket??

I'll let you know what it was when I remove the head, but that might not be for a couple of weeks.

cheers

Matt

[R31Nismoid]

Hard to tell without removing the head as it could be either of the things to stated!

Maybe the gasket was faulty, unlikely but possible.

Then the same for a crack in the gallery/jackets etc.

Interesting one Matt, be sure to post back up about it

[BOOSTD]

I don't think it was a faulty gasket, it has been in for 10 months. I'm going to check now if I have a snapped head stud

[kwazza11]

I blew a tomei metal head gasket, but it was the center two pots that did it and the gasket cracked both on the same side, i used to be fairly unkind to it when cold though and my motor has been bored another 3mm so the coolant to cylinder gap is much smaller, but more than likely blew it by boosting it before everything had warmed up and expanded.

learn from my experiance! be nice to your motor...

[BOOSTD]

ok, good to know that they actually can let go like a normal gasket

[kwazza11]

Just make sure you get everything machined nice and smooth as with metal gaskets everything needs to be spot on, pay attention around the head bolt holes if your just going to clean up the block as they can tend to pull up if they've been overtorqued.

Edited February 21, 2007 by kwazza11

[T04GTR]

get hold of a borescope.

orr... carfully drain the coolant out of the head. by taking the top hose block of the head. then presurise it and see if it still leaks.

cracks in blocks dont go away either, im suprised they actually went ahead with the build after seeing that

[BOOSTD]

Turned out to be a small scratch on the surface of the head between a water gallery and the bore. Head gasket wasn't damaged at all. The copper gasket cement must have kept it sealed until now.