halocline
Contributor
Even though the piston edge is dull, it couldn't hurt to use a bullet, if you could figure out a way to keep the bushings in place. I don't have the MK20 installation tool, mostly because I don't have a MK20. The few I've rebuilt I just install the bushings, or-ing, spring, and seat, then push the piston in; the seat carrier installed is supposed to hold everything in place. So far it's worked fine, but eventually I'll have to get the tool.
In this case clearly there was something wrong with that o-ring or one of the bushings. The bushings are cheap plastic parts, and they do contact the o-ring under high pressure. So, a tiny burr or flaw in the bushing could conceivably chew up the o-ring. Just a guess.
Another reason to stay with the MK5/10, I suppose.
In this case clearly there was something wrong with that o-ring or one of the bushings. The bushings are cheap plastic parts, and they do contact the o-ring under high pressure. So, a tiny burr or flaw in the bushing could conceivably chew up the o-ring. Just a guess.
Another reason to stay with the MK5/10, I suppose.
