Can this cylinder be repaired

[HARRY D. NICHOLSON]

Is there a repair for this cylinder damaged by loose piston pin cutting grooves into the wall? Caille Liberty Twin.

[Mumbles]

It probably could be but it would take a competent machine shop and deep pockets to do it. Unless it could be bored oversize and a matching piston found, it would require resleeving back to original bore size so a standard size piston could be used.

[Tubs]

In the 1960’s there were 4 automotive machine
shops in the city where I lived at that time. One
was owned by a good friend. He employed 4
people. As time went on he didn’t have enough
work to make a living just for himself. No body
fixes anything anymore. Now there is only one.
Also a friend I made 55 years ago when he
worked at one of those other automotive
machine shops. He specializes in 50’s & 60’s
Chrysler performance motors. I suspect he could
sleeve it but I doubt I could talk him into it. Its
what has to be invested for a one time job while
he could be doing more profitable work.
But if I could get him to sleeve it, how would
he match the ports to the sleeve? Exhaust can
usually be accessed from the outside but what
about the intake? Cutting them in before inserting
the sleeve creates another set of challenges. That
one question I would be asking someone willing
to do it.
Tubs

A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.

[HARRY D. NICHOLSON]

Thanks for your responses.  Replacment cylinders have apparently been located. There were no cotter pins holding the pins in the pistons.  Wonder why.

[Tom]

Piston pin grooving is a very common problem with the Model N Sportwins.  Difficulty lining up the holes in the piston and pin during assembly, using the correct size and material cotter, and knowing how to distort the pin once in place were likely contributing factor.

I’ve run a few motors with grooves worse than yours.  They sound a little funny.  But remember that they ran long enough to do the damage.

T

 

[Tubs]

HARRY D. NICHOLSON wrote:

Thanks for your responses.  Replacment cylinders have apparently been located. There were no cotter pins holding the pins in the pistons.  Wonder why.

Part of the hobby is the search. Sometimes for a
motor, information, but mostly for parts. I think
you’re fortunate this search ended for you so quickly.
Tubs

A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.

[PM T2]

There are some options other than re-sleeving or boring out for an oversized piston, but they involve welding that is beyond the scope of what most of us are capable of. That being said, I have seen some cylinders that exhibited evidence of the wrist pin gouges having been welded up and t he bore machined round afterward. One of those motors is an Elto Hi-Speed Speedster that I got as a project motor from Sam Vance. The welding and machine work had already been completed. everything fit together well and the motor makes lots of compression and I have run it.

Best,
PM T2

He's livin' in his own private Idaho..... I hope to go out quietly in my sleep, like my grand-dad did..... and not screaming, like the passengers in his car...

[joecb]

Oh yes the dreaded wrist pin gouge.  I believe that the failure originates with the severing of the cotter due to slight radial movement of the wrist pin. Having also encountered this in an “N” , silly me took up the challenge of sleeving the bore.  First off, the sleeve was pretty costly, next lacking a mill with sufficient quill travel this became a lathe boring job. Next problem how to secure the cylinder in the lathe. Didn’t feel confident with a secure hold in the “4 jaw” , I opted for a beefy tubular fixture permitting location off the gasket face. After fitting the new sleeve… cutting the ports. I hope that by this point you get the “picture” …. either find a good cylinder or as T2 suggested try welding.

By the by, the motor went back together and ran fairly well. Another example of a $XXXX repair on a $X. A learning experience!

Joe B

[HARRY D. NICHOLSON]

Joecb: Your pictures define the phrase – a picture is worth a thousand words.  Good pics.  It appears that there are more than a few Liberty Twins missing the mag resulting in parts availability.

[George Emmanuel]

I’ll echo Joecb’s comment and this is how I solved it. I don’t remember the brand but it was a cotter pin/wrist pin type and the existing pins were not tight. The motor had never been apart, so I know the factory installed the pins. The correct size cotter pin would fit the hole in the piston boss and also in the wrist pin, but once assembled, it wouldn’t go through, so they used a slightly smaller pin and that’s where the movement came from. There was an ever so slight misalignment between the holes in the pin and boss. First I aligned the boss hole you could see with the hole on the wrist pin and then used the correct size aircraft drill so I could reach all the way through. There was only a slight misalignment and the drill took care of it. The new, correct sized cotter pins went in and were tight!

George

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