spiral or ring type piston pin retainers

[Rich Biebel]

I was in the engine machining and building world for many years and not once can I recall seeing round wire pin locks....from any of the major piston manufacturers.

Round snap ring type was common.....double per side and then spiral locks were the most common.

Yes they tear up your fingers and usually end up with some blood involved.

They made a tool for them but I developed a pretty easy method of getting them in and out.....no blood....usually...

I would guess the round wire lock does not pound out the groove like a flat lock does making it harder to disassemble pistons after some use...

I also assume the round wire lock groove is cut to fit the lock and if done wrong bad things happen...…

I usually Learn something new everyday...but I'm sticking with spiral locks.....LOL