Guzzino Big End

Hi, well the frame etc of my very sad 1953 Guzzino is completed now , together with newly built wheels. The pin striping on the mudguards looks great; really finishes the paint job. I’m slowly getting there !!
Now I’m working on the engine and have a possible problem.
The engine is in a bit of a mess. It was bone dry inside. Not even a hint of oil, so not surprisingly every bearing and bushing is completely shot to pieces.
EXCEPT the big end which has no up and down movement, but does wobble from side to side. So much so that the con rod has been rubbing the inside of the flywheels !!!
It is as if the flywheels are not completely pushed together.
So…can anyone please advise on how to split and re-assemble the big end assembly so I can try and resolve this issue. Is it just a press fit ?
On the same theme, what is the correct tolerance between the brass fuel inlet valve bush and the crankshaft ?? How much “slack” can be tolerated ?

from memory, you need a press to pull the flywheels apart, then you fit a new rod complete with big end, which is pressed together and then aligned, lots of smaller engineering firms specialise in this work, many can refurbish your connecting road and fit new bearing and bush

If the flywheels weren’t completely pressed together, I would have thought that the cases would no longer bolt together. There isn’t much spare room between the crank support bearings.
The manual for my Stornello does give a dimension for the side play on the crank pin, maybe youes gives similar?

Thanks for the replies, guys.
Unfortunately I thought that i had posted this enquiry some months ago, but clearly I failed ( and still do ) to master the technology. So I am now in the process of rebuilding the engine having left the flywheels as they were.
My current query is what is the correct chain spec and length for the Guzzino. My manual says 1/2 x 3/16, but no indication as to the number of links.
any help please ??

The chain appears to be fairly common and has a ref of 083. You can buy a 5m length for £25 from Simply Bearings! It’s easy to cut it to length with an angle grinder etc. It looks like the link may need to be ordered separately.

Thanks Don. You always come up trumps !!

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