Horrible misfire - where do i start?

[MarkyB]

A rarity unless you are thrashing the nuts off it I'd suggest

[IslipMinor]

Hopefully, yes!

[super trimbo]

Thanks everybody for all of the responses, this is so wierd as my pickup did the exact same thing (misfire, but not fuel /electrical) 2 weeks ago , which is why i've been using my van. This evening i wandered if the pick up might be an easier fix (so I can get driving again, hate modern cars), so I ran a dry and then wet compression test with the following results *Engine in the pick up is bog standard 1098

Dry
1: 60 psi
2: 60 psi
3: 160 psi
4: 160 psi

Wet
1: 60 psi
2: 60 psi
3: 160 psi
4: 160 psi


Firstly assuming my opinion is right which it by no means forced to be, I think this means the rings must be okay as the wet/dry readings are the same. With it being 1 & 2 that are down on compression i'm rather hoping it'll be a head gasket which is easier to fix than the suspected ring in the 1275 van in the short term to get me going. Ran out of day light, next plan is to have the rocker box off the 1098 and see that the valves are moving ok (not stuck etc, or zero clearance), assuming all is good there should be the headgasket? Be bloody unlucky to burn valve seats on two opposing cyl otherwise?

Thoughts everyone?

[MarkyB]

It's the head gasket, Roy would have changed it by now!

[Dominic]

99% certain - no I'll be brave and stick my neck out - 100% certain it's the head gasket. Cheap and easy fix luckily (as long as you've not run it for long in this condition)

[super trimbo]

Dominic , you was right![frame][/frame]

[bmcecosse]

You still not got it changed???

[super trimbo]

Ah Bmc !

Not the most competant of mechanics, I have learnt myself as I've gone along having no knowledge at all when I got into moggies a couple of years ago - To being able to (slowly) work my way through a problem and fix it.

Spent an hour getting the head off this eve, will spend however long it takes tomorrow eve putting it back with a fresh gasket

[Trickydicky]

Thats the second minor head gasket I have seen with that issue, what causes it to happen? could it be the head is not torqued down evenly?

[bmcecosse]

Can be - or 'pinking' in the engine, or just a good overheat - or of course any previous damage to head or block in that area.

[alexandermclaren]

Ah Bmc !

Not the most competant of mechanics, I have learnt myself as I've gone along having no knowledge at all when I got into moggies a couple of years ago - To being able to (slowly) work my way through a problem and fix it.

Spent an hour getting the head off this eve, will spend however long it takes tomorrow eve putting it back with a fresh gasket

well done
great that you are willing to try

[super trimbo]

Just on topic here, which are the best head gaskets the copper ones or the slightly cheaper ones, that are silver in colour?

[bmcecosse]

Copper!