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CB750/4 water damage to pistons

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Nurse Julie:
Graham is stripping a very, very early engine today. This engine has been stood for not far off 50 years after sustaining chain damage to the crank cases. The engine has done probably less than 1000 miles as other parts are original and in excellent condition, although most parts will need replacing due to age related deterioration. The pistons were seized to the bores and 1 piston in particular has sustained a very similar type of damage to what I found in my CB400/4. Graham always insisted my damage was caused by water ingress a long time ago, with rust forming, eating in to the metal, with the resulting catastrophic damage when someone 'unseized' the engine probably with a big breaker bar and a lot of force and then started the bike and rode off into the wild blue yonder.
I think this just shows what damage can NOT be seen, when buying an old engine that has sat around for many years.

Photo 1 shows totally destroyed rings, lands and piston. Photo 2 shows the top ring being eaten away.

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SamCR750:
Wow. Makes one wonder what else might have gone the same way.

UK Pete:
Wow that's servere, 

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MrDavo:
Ouch!

No doubt it ran fine when treated to a little easystart squirted into the carbs.  ;)

K2-K6:
Wow, that's really far gone.

Be interesting to see the top of that piston on the combustion face. If it's just been damaged by corrosion and removing the barrels then it should have no other signature of damage if it's not been run after the event.

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