Oh No ....

[nick heppinstall]

Looks like I may have a major prob with the 400 typical. It runs like a dream all year then summer arrives ... Went to York last weekend and she developed a very slight missfire on the way back. Just been to get her out of the gararge and there is a puddle of nice clear coolant on the floor. It had pooled at the top of the engine at the back between the rocker covers. Just above the bell housing below the 2 little heater hoses. I mopped it up and backed her outside and watched. Coolant started to gather again in same spot..... Sorry for the rubbish description. I have a picci to mail if anyone wants to have a look. What do you all think ? .... Hope their are no Razer blades in the house ...

[domster]

Head gasket failure?

Difficult to know without seeing the car. Besides I barely know one end of a wedge from another.

Most coolant leaks would not cause a misfire, but a head gasket failure would cause both symptoms.

[andymadmak]

You sure it's not just a leaky hose? Tighten all the clips and stuff and see what happens. It may just be it dribbled some water onto a plug/lead, hence the missfire. Does the leak go if you open the heater valve? (might suggest a blocked bypass hose if so, hence the system pressurising and leaking at a hose union) Have a peak at oil and water too, see if theres any sign of mixing in either. (although thats not completely fool proof)
Stay calm Nick! Even a head gasket is not the end of the world on these beasties (Its only a pushrod lump when alls said and done!)
Good luck !

Andy 400se

[nick heppinstall]

Thanks Andy ! I've looked at all the hoses and they look OK. No leaks that I can see. Oil looks clean as does coolant. Talked to Mr Thorpe who was very reasuring ! Said " Don't panic ! " Top man ! Apparently there is a gasket below the plenum that could be shot and he said it was likely to be that. Having the manifolds done next week so he said he'll whip the plenum off etc and replace the gasket. Must admit feel a lot better now !

[tcpc]

if it's not one off the two hoses above the valley gasket, then it could be the valley gasket it's self,
they are not alot off dosh and are striaght forward to replace,
i bought a top end gasket set when i had a top end rebuild and that included the valley gasket and i think it was around £50 for the whole kit,
if all the hoses are ok then see if any off the bolts that hold the intake manifold to the block have not come loose,

tony

>> Edited by tcpc on Monday 9th June 21:04

[nick heppinstall]

Tony. Yeah it's looking like the Valley Gasket. I can see bits of it and if I pull 'em they just flake off. Looks like it's knackered.

[tcpc]

thats good in one way, if you had to play with the head gasket then you should have the head skimmed to be on the safe side,
glad you found the problem,
tony

[danny hoffman]

It sounds like this leak is too high to be the head gaskets.

[jeff m]

Pressure test it.
That way there's no guessing.
Jeff