#14
Post
by bokusouchi » Fri Feb 09, 2024 6:14 pm
I also have this problem : ( when sprocket cover is off , the oil pump cover leaks quite a bit ).
But not only that : It still leaks a little bit when the cover is back ,now ....
I decided to replace the pump cover paper gasket . It is NLA , but I managed to find one on Ebay .
Failing that , Yam-bits has some refabs .
To Remove the pump cover , One needs to remove the generator cover , the flywheel (using a fly-wheel puller )
then remove the generator back cover ...
I put a very thin layer of liquid gasket on both sides of the new gasket , I hope it will make it more "leak-proof" .
When looking ar the 51x workshop manual (page 101 ) , I found that the oil pump cover has a "normal" fourth bolt ,
and that the sprocket cover has no pass-through bolt (!).
The pictures were probably from a pre-production model .
For Production ,Yamaha decided to put a pass-through bolt . My guess is that they wanted to beef up the clutch mechanism .
(the clutch mechanism pushes back on the sprocket cover ).
This shows that the design process of the RD/RZ/RZV was not at all smooth but rather with a lot of backtracking .
(But we knew that already ...)
By correcting a possible problem with the clutch ,they created a leak problem with the oil pump cover .
No wonder the gasket became NLA , as a lot of people probably tried to replace it .
Operation was completed this evening . I will do the oil refill later , and see if the leak is fixed ...