Sq.4 Mk1 (Series B, suffix X) Cylinder block dimension?

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Holder of a Nylon Anorak
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Sq.4 Mk1 (Series B, suffix X) Cylinder block dimension?

Postby john.bebb » Thu Oct 11, 2018 7:51 pm

It is time to resurrect my 1949 Square for the nth time (but properly, this time!)…
… new bearings throughout, new rods, liners, pistons etc…

I do like John Witing's comment to Gui Dovey posts; -

"Gui.......you have misunderstood the instructions that come with a Sq4.........its money that you throw in the bottomless hole.....not the bike."

The engine cylinder block (& head) have doubtless been skimmed a fair few times.

I would like to know the ORIGINAL dimension of the block height; - i.e. base to crankcase mating surface to block to head mating surface.

Such will enable me to procure a base gasket spacer and possibly also equivalent spacers for the tappet guide blocks.

Yes, I know I could derive the requirement by a dry-fit and measure the piston protrusion…
but such becomes considerably time consuming…

So please; - (perhaps Bruce Longman(?)) or other with access to serious technical data,
can anyone supply such information? Thank you.


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Re: Sq.4 Mk1 (Series B, suffix X) Cylinder block dimension?

Postby paul.jameson » Mon Oct 15, 2018 8:12 pm

4.435 to 4.440 ins is specified for the MK II. I don't have a dimension for any other model.
Paul Jameson
36 4G, 37 VH, 54 KH(A), 75 Healey 1000/4, 52/53 ex ISDT KHA (project).
Former Machine Registrar & Archivist, General Secretary and Single Spares Organiser (over a 25 year period).
Now Archivist once more - but not Machine Registrar.

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