71 replies to this topic

[sledgehammer]

my money on Head Gasket - or stud streched / broke leaking compression into pushrod area

 

would 2 pistons fail at the same time ? - would be rarer than head gasket

[Cooperman]

So long as you have a decent tool kit it should take around one hour to remove the head.

Undo the bottom hose at the water pump to let the water out first. Then remove the top hose. Remove the radiator bracket. Remove the rocker cover. Undo the exhaust connection behind the engine. Remove the manifold nuts and push the carb, inlet & ex. manifold towards the bulkhead. Undo all the head nuts and the rocker shaft nuts. Remove the rocker shaft. Remove the push rods giving each a wiggle before pulling them upwards to ensure they disengage from the cam followers. Keep the push rods in the correct order when re-fitting.

If fitted, undo the by-pass hose between head & water pump.

Pull the head from the block.

 

I think that's about everything, but I might have missed out some minor detail, which will be obvious when you do the job. It is very easy.

If it is a HG, change the oil & filter before running.

[BronkoMini]

Many thanks I'm going out now to take it off.

[BronkoMini]

Was struggling to get the inlet manifold off and now the garage lights bulb has blown, will have to try again tomorrow.

[jpw1275]

Once you have the head off can you take some pictures

Cheers james

[BronkoMini]

Once you have the head off can you take some pictures
Cheers james

Yep will do

[BronkoMini]

Head off and head gasket blown between 3 and 4, no4 piston is really clean compared to the rest, not much scoring on the bores, how can I test to see if the piston rings are gone to? Also on the head where te gaskets gone there a build up of carbon, I shall look if the heads still straight, also so note the head stud between 3 and 4 came out with the nut, not sure if that may have had some thing to do with it.


So what are peoples thoughs?
Thanks

[BronkoMini]

Upon cleaning up the head and block it looks as though there is a small hairline crack between cyl3 and 4 where the gasket went, is this terminal? The crack goes down to just above the piston tdc. What can I do, if I put the new head gasket on will it last for any time?
Thanks

[myredmini]

I think the blocks scrap now its cracked sadly.

[jpw1275]

As said the block is no good unfortunately

Cheers james

[BronkoMini]

I think the blocks scrap now its cracked sadly.

  

As said the block is no good unfortunately
Cheers james

That is really annoying the engine wasn't really cheap, any way I have put the head back on with new head gasket and see if I can make it to castle Combe and then I'll get the engine out, that poor meight off the road as I won't have time to do the repares as I'm off to uni. Sad times, I'm actually quite cheesed off.

[Cooperman]

You will need a replacement block, plus new pistons and a re-bore. The head may need a light skim if the 'blowing' has eroded the head face.

Alternatively try to find a good complete engine, but do a partial strip & check before fitting it putting new main, big end and thrust bearings in, plus a new oil pump & timing chain. To do otherwise is false economy.

Ah, the fun of running classic cars!

[BronkoMini]

You will need a replacement block, plus new pistons and a re-bore. The head may need a light skim if the 'blowing' has eroded the head face.
Alternatively try to find a good complete engine, but do a partial strip & check before fitting it putting new main, big end and thrust bearings in, plus a new oil pump & timing chain. To do otherwise is false economy.
Ah, the fun of running classic cars!

I still have another engine that needs rebuilding so I'll do that when I get time, just wondering why the pistons need replacing as they don't look damaged?
And the head has been slightly marked where it blew, so I shall get that skimmed.
Thanks for the help.

[Cooperman]

It is never a good idea to fit old pistons into a different block. You would need new rings anyway and the bores would need a hone, so new pistons and a re-bore to the next size up is the way to go.

[BronkoMini]

It is never a good idea to fit old pistons into a different block. You would need new rings anyway and the bores would need a hone, so new pistons and a re-bore to the next size up is the way to go.

Ah ok, thanks