the correct "official" answer is that you need to pull the motor from the frame to perform that task.

if you are very careful and know exactly how to position the crank/cam you can do it still in the frame.

at a minimum you need to remove the cam chain tensioner.

the risk is that you can destroy the cam bearing by removing the end cap. the cam bearing is just a plain bearing cast in the aluminum end cap. if you remove or install it under tension the steel cam scores and distorts the bearing. you won't know it at the time and it will start and run fine for a while but will fail prematurely.

your call on how to fix. when I have this problem I ALWAYS remove the engine and do it properly...and I know where to position the cam/crank to do it without load...the only reason I'd do this still in the frame is if I was on a trip and had to fix it quick to get home.

there are lots of folks who have done it in the frame and put so few miles on their bikes they never know the difference

 

NO.... To do that PROPERLY, You WILL need to remove the cam-chain tensioner, the dyno cover, the tappet adjustment covers, and Possibly the top (breather labyrinth) cover (engine out of frame) as well as the Tach-side head cover in question... The tach drive MAY come out with it........Simply replacing the gasket on the head cover you remove requires re-verification of camshaft axial clearance which MAY (although unlikely) require re-shimming the camshaft....In the unlikely case you remove the breather cover, you will have un-torqued ALL the head stud nuts, so the head gasket may now be in question......
Obviously, this would be "worst case" type scenario......
I am sure it can and has been done without all that dis-assembly by a mechanic who is well experienced with these engines, BUT .......

Edit: John beat me to posting and he IS the expert on the 350's.....But you can see we are in agreement.....

 

Massive thanks for the replies.

Absorbent padding under the drive cover for the rest of the summer and then a winter strip!

 

Ok so the winter strip is well under way

The only problem I have left, before re-assembly, is how do I remove the old camshaft oil seal?

I thought I'd replace it along with everything else....


Thanks in advance for any replies,


Nasher

 

When you open it up pay careful attention to thow the Gasket is installed.

They "LOOK" symmetrical BUT... They are not.

They can be installed in a way that will PINCH the O-Rings that seal the Rockers and cause the same symptom of leaking that you describe here.

Just a thought as I did the above and had to pull things out and re-do it once.