18 replies to this topic

[Cooperman]

Personally I wouldn't want to give an opinion without seeing a photo of the damage. You also need to check the piston for any cracking if it has existing damage.

[1977 Loud_Mini]

Here is a picture of the damage. They only go as far as a lip on the inside of the piston at the bottom which can just be seen in the picture. No cracks anywhere beyond this.

[Cooperman]

That looks very odd. It doesn't look like piston balancing where metal has been removed to achieve equal piston weight. It looks as though it may have been damaged and the piston repaired by cleaning out the damaged areas and polishing to prevent cracks starting.
However, the basic piston looks fine so whilst no-one could be definite about it, it may well be OK to re-use.
Really it's up to you whether to take the chance, bearing-in-mind that as it's a 1380 over-bore, should a piston 'let-go' you may not be able to bore to a larger size. A 1380 may or may not go out to 74 mm. I've seen blocks which don't and they are then scrap.
Of course, it may well all be fine.

[1977 Loud_Mini]

That looks very odd. It doesn't look like piston balancing where metal has been removed to achieve equal piston weight. It looks as though it may have been damaged and the piston repaired by cleaning out the damaged areas and polishing to prevent cracks starting.
However, the basic piston looks fine so whilst no-one could be definite about it, it may well be OK to re-use.
Really it's up to you whether to take the chance, bearing-in-mind that as it's a 1380 over-bore, should a piston 'let-go' you may not be able to bore to a larger size. A 1380 may or may not go out to 74 mm. I've seen blocks which don't and they are then scrap.
Of course, it may well all be fine.

Thanks for your help it's much appreciated. I will take a chance with them, atleast if anything does happen i've still got my standard 1275 to revert to.

Evan.