Very aggravated... Just split case to redo seals and crank was bad. I replaced all new seals. I noticed groves on the clutch shaft that goes through the casing to the clutch basket near the left side (so I replaced it with a newer one). Left side of bike. First run after rebuild and have oil leaking at clutch rod. I am not sure why this going is happening after putting in new seals? Any ideas?
I thought that is was damaged the seals before e splitting the case due to the groves on the clutch rod. but it is now doing it with the new one. Any ideas are helful
Maybe replace the clutch push rod if it has grooves and is damaged
i have a new specific rd400 one if you need it, ordered it by accident.
Is the vent on the top of the case doing its job?
Was your replacement rod new or did you source a used one? The OEM push rod 328-16357-00-00 is still available from Yamaha.
Did you use an OEM seal? Part # 93109-08061-00
Possibilities?
1) replacement push rod (if it's a used one) is slightly worn at sealing surface
2) new seal is bad (recently saw this happen on a AT2 build by a YouTuber I follow, Dale Sweger). It's rare but they can be bad right put out of the package.
3) new seal isn't installed correctly (is it possible it's in backwards?), or the lip is folded over.
My 400 pushrod was same condition as you described, ordered a OE unit from partzilla, about 30 dollars. Ball and pusher looked great.