Hers one for you,
The seal isn't what usually leaks!!!
Replace the thick copper washer under the impeller dome nut, you will probably have to get the Honda part as its an odd size.
Dont ask me how i know this I actually used to do the cam chain mod INSIDE the Honda warrantee time!!!
I did quite a few of the cam chain mods as well, from the original 'place two punch marks in front of engine number on left crankcase side' to the last 'fully automatic' ones which weren't
I got it down to about 1.5 hrs eventually (did a lot I think
)
Haven't seen inside one for about 20 yrs though (aah, the 'good old days
)
That washer was almost always squashed by the nut and could prevent the impeller tightening on shaft correctly ( to pre-load seal)
I seem to remember the hardest part was removing generator rotor to get to chain tensioner, until 'we' got a 50 ton hydraulic puller