The piston gear didnt seem to be very tight to when inserted by the O-ring but that with the plastic housing. Tomorrow i am pulling that and trying it again with aluminum housingSounds like you have the seal in it. Sometimes new stuff doesn't come complete.
A little confused by leaking there, does the O-ring fit tight into the case when you insert the adapter/sleeve for the gear? It really can only leak past the O-ring or the seal, UNLESS the case bore is gacked
Fingers crossed