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Pistons

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Can anybody tell me if these are the pistons that everyone warns about the top coming off. 

Piston

I’m building a 72 commando for a friend, it came as an unfinished project, with a newly rebuilt engine. Curiosity got the better of me so I stripped the engine, luckily found it had these pistons, with an odd pair of rings and an SS Cam with one of the lobes welded up, a damaged pair of followers, and a bent push rod. Looks like I’m looking at replacing the lot.. ??

 

It is difficult to see from the photo, but if there is a slot in the oil ring land they are the piston that has reported failures, especially in Combat engines.  If there are only the "apostrophe" slots in the skirt, they are the interim "Combat" piston which are considered acceptable.  The later 850 pistons eliminated these as well.

Ron L

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I would say they would be Ok ,but with the other evidence of poor workmanship I would check ring gaps and circlip fittings plus a good wash out ,as there is evidence  of  grit in that motor.

 


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