what caused this spiral locks

Well I was cleaning the motor up to start putting it back together but came across 3 pistons where the spiral locks are backing out and one on one of the pistons I found a piece of the lock that broke off in the oil pan. So what would cause this?
Forged rods with ICON pistons I know I need to replace all of them but not sure what I should use or the part number for the locks any help would be great.
thanks
http://www.supermotors.net/getfile/1057298/fullsize/20150508_182238.jpg
http://www.supermotors.net/getfile/1057299/fullsize/20150508_182302.jpg
http://www.supermotors.net/getfile/1057300/fullsize/20150508_182334.jpg
http://www.supermotors.net/getfile/1057301/fullsize/20150508_183041.jpg
http://www.supermotors.net/getfile/1057302/fullsize/20150508_183111.jpg

well I would say that maybe it was not all the way in the groove or the groove is not deep enough for the lock??? or maybe you bent it when installing them and they lost the tension???

I have seen this a few times when two single .041"-spirolox were used in place of a double wound single spirolox, (.076" thick).

The outside loc won't going all the way down into the groove.
That's not to say it was the cause here.

so what spiral locks should i get for these pistons or is there something better

why not use the nylon buttons?

muddog899 wrote:so what spiral locks should i get for these pistons or is there something better

Use whichever ones are correct for that groove width and wrist pin length.

the part was a PRG-110 there ordered and on the way

Some times the pin to lock clearance is too tight and pin flex causes the locks to push out. When locks break segments it is usually from detonation. While some manufacturers recommend stretching the lock out before installation , I NEVER do. If the lock is put into the grooveas a coil and compressed , the energy wants it to spring out. If it is installed as it is supplied , it lays flat in the groove. While many like spirolocks, the better method is round wire locks. Aluminum pin buttons should only be used in a high maintainence situation where the engine is constantly coming apart. ( well IMHO) True Arc ( snap rings with eyelets) lock rings often break the eyelets off at high rpm of if detonation is encountered. Press pins should only be used on stock to low performance applications.