Thread: 1955 S1 rebuild

I don't profess to being an expert either, but concur that it is a 2 litre. By the look of your pic, I would say that engine is a siamese bore.

I would say It's a spread bore as the studs show for the full flow oil filter
on the RHS. The walls between 12/34 are thinner on the siamese motor.
Is that some damage between 1/2 cyls or just the camera
Now if the engine is 40 thou and has some wear and to allow for a hone clean up to get the rust pits out. You will have to mic the bore to see what size pistons you will need. Remember the piston bore clearance is critical for heat transfer. Better to do it right. If that is a dent between 1/2 it may give problems with head gasket sealing...........Mark

As already stated it is 2L spread bore. You need to get that mark between 1 and 2 looked at and the bore size checked before you buy pistons mate or you will be wasting money. Depending on the depth of that damage you may be better off looking for another block.
Dennis

The difference between.........
siamese bore left
spread bore right...Mark

that damage between 1/2 bore is me when i was drilling and hammering out the old piston i slipped once on the hammer and the blow slid across the top. bugger. how do i fix that ? does this need machining to flatten back down to a smooth finish.

Im now thinking maybe its cheaper to find a replacement engine altogether & stripped it. not sure what they fetch in price but could be cheaper then buying bits n pieces for this one. not sure yet. I will call around and see whats available & what price and post results. cheers

The piccy don't look good for the damage.
only my guess is it would bee too mutch to re face the block deck height.
You will have trouble with the piston deck height. Eg pistons sitting too high
not to mention push rod length ect. If you take too mutch off the block you will have trouble with the pistons hitting the valves head ect
a lot of things come in to play there, with doing all that.
May be cheaper to find another block. That's only my guess.... Mark

Originally Posted by shamirj

that damage between 1/2 bore is me when i was drilling and hammering out the old piston i slipped once on the hammer and the blow slid across the top. bugger. how do i fix that ? does this need machining to flatten back down to a smooth finish.

Im now thinking maybe its cheaper to find a replacement engine altogether & stripped it. not sure what they fetch in price but could be cheaper then buying bits n pieces for this one. not sure yet. I will call around and see whats available & what price and post results. cheers

I would find an engine overhaul shop that does block machining and talk to them. It is hard to tell from the picture just how bad it is. Fortunately it is an area that does not have the piston running on it. It is possible that some form of, for example, metal spraying could be used to build it up before resurfacing the block. If you can find an engine in better condition, that would be the way to go.

John

Don't forget that the block is already out to 40 thou
metal spraying on such a localised area and deep as well
The small area will probably lift when heated in service
as slightly dissimilar metals are applied. Remember 1950's cast iron
and todays cast iron.......... Cast iron metal spraying is iffy in my oppinion. Seen too many failures. That would be in the hot area of the exhaust valve. Pinning or stitching . It is too close to the head bolt hole.
Remember that those old blocks will have a considerable wastage on the inside of the water jacket. By all means get a quote, Re boring and all the other work will far exceed a good second hand block. Those old blocks
are starting to show all their problems now....Mark