TightlinesTN
Recruit
- Joined
- Nov 13, 2025
- Messages
- 1
So I've been chasing down a leak on my Nissan NSF15C coming from the diaphragm cover that has been causing a rough idle. I replaced the plunger and the idle smoothed out, but I still have a small leak coming from the same spot. When I replaced the plunger I noticed the parts diagram showed two o-rings (1-37) under the plunger. But when I took off the old one there was only one and it was on top of the plunger (picture attached), not where the parts diagram showed. I installed the new plunger with only one o-ring in the same spot as the old one. I'm wondering if anyone else has had this issue or knows where the second o-ring is supposed to go?
