As REDROCKET stated, this is actually the back cover of the pump. The snap ring is holding the cover in place. There is an o-ring under that cover. Any pump can and will have o-ring failures.
That being said, with our Adrenaline pumps, if a customer has a leaking o-ring anywhere
- we have been sending out new pumps not typically just new o-rings. We are doing this to eliminate the customer having issues from the installation of the o-rings but also to evaluate each pump to make sure there isn't something going on. There have been about 20 leaking back cover plates out of 1000+ pumps. I imagine that is at least as good as stock. So, I'm happy with that and there are no signs of anything funny going on or something bad in the pump that requires attention - just normal oring failure. We'll continue to send replacement pumps for any oring leak issues for a few more months. At that point we'll have a full o-ring replacement kit with instructions and loc-tite so that customers can change their own o-rings upon failure. The back snap ring is especially important to seat perfectly so that it does not cause a failure down the road so we'll have instructions to make sure those are seated perfectly when we are no longer sending replacement pumps for these issues.
Unfortunately, until now, a leak from an O-ring on the back cover or the non-serviceable plug in a stock pump meant you had to buy a new pump. We already offer the replacement non-servicable plug and will offer a complete HPOP O-ring kit so that if you have a leak with a stock pump or one of our pumps, you can fix it. You won't be stuck buying an entirely new pump or waiting for us to send you a replacement.
RED ROCKET Your replacement pump is on the way, but make sure to check those ICP pressures after you get it installed. We have you check for high ICP pressures because excessive ICPs cause excessive internal temperatures. While that isn't hard on the pump, it is hard on the orings and will eventually cause failure of the oring. Call here anytime you have any questions or issues and thanks for following up on your post.