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Engine
#1
Well back from Goodwood in Josie whose engine was a bit rumbly so take the spare engine out of Poppy, put Poppys original engine back in and then take Josies engine out and replace with the spare. Get to a local meet in Poppy and broke down and recovered to home.
Damn I found I hadn’t repaired Poppys engine from when I put the spare in.
( last year Poppy and I started a JOG and broke down south of Coventry with a loose fly wheel)
So remove engine and gearbox (again) fit new tab washer, lap flywheel, fit loctite and tighten nut.
Re-install engine and gearbox including radiator all ancillaries and floor panels, engine running fine with a bit of fine tuning to be done after a road run.
Can’t disengage the clutch!
So take out the engine and gearbox and found the tab washer needs to be trimmed to enable the clutch to disengage! I knew this so why didn’t I do it?
Anyway re fitted engine into Poppy and all working. Hurrah.
So started the strip down of Josies engine and I think I have found the source of the smoke or steam as seen on the Goodwood video I posted last week ( also the several head gaskets I have fitted).
This engine has driven Josie and I to JOG/ LE ,the Scottish A7 rally, MIM, Prescott hill, Beaulie and Goodwood.
How will I repair this?
What are everyone’s thoughts?    
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#2
Hi

Those cracks round the centre stud are supposedly pretty common, and are possibly due in part to the stress when having liners fitted. My own engine has two fine cracks here, but it doesn't seem to prevent the gasket from sealing OK with no special measures needed. I wouldn't tune it up and go racing though.

Of more concern would be what appears to be quite deep pitting on the block upper face, which ought to be refaced flat. This may then require the addition of a metal shim plate between block and crankcase so that the piston crowns are still clear of the head. You will have to balance the cost of this against sourcing a better block.
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#3
(23-10-2022, 09:51 AM)John Cornforth Wrote: Hi

Those cracks round the centre stud are supposedly pretty common, and are possibly due in part to the stress when having liners fitted.  My own engine has two fine cracks here, but it doesn't seem to prevent the gasket from sealing OK with no special measures needed. I wouldn't tune it up and go racing though.

Of more concern would be what appears to be quite deep pitting on the block upper face, which ought to be refaced flat.  This may then require the addition of a metal shim plate between block and crankcase so that the piston crowns are still clear of the head. You will have to balance the cost of this against sourcing a better block.


Agreed. 
From what I can see of the valve seat that block has led a hard life.
I’d start with another block, but others will champion the reuse angle I’m sure

Charles
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#4
The block looks to be lined and the two radial cracks look to go down behind the liners so, probably, not too much of a problem in themselves. A far bigger problem, though, is the pitting to the block face. Yes, you could remedy that by re-facing the block but the pitting looks quite deep in places so a fair bit of the face would have to be removed. Given that the top of the block isn't overly thick to start off with that might prove to be an excessive amount notwithstanding that doing so would have the potential to fatally weaken the already weakened area around the cracks. I'm afraid I'd be looking for a better block.

Steve
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#5
Shimming the block to compensate for loss of height after skimming is one way, you can safely skim 20 thou or so from the crown of Seven Workshop pistons as an alternative. Not sure about other brands.
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#6
    So the general consensus is a new block. I have a spare block under the bench so will cleanup and work on this. Thanks everyone.
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