Topic: rubber plugs under cam holders

[kenzie]

Just doing a top end rebuild on my 73 cb 750, I keep hearing horror stories about the rubber plugs under the cam holders leaking , nobody wants to have to pull the engine twice, does anyone know how to be sure they will not leak? Ive heard silicone, but also heard that isnt a good plan either. Thanks for the help!

[oldfart]

Stock ones don't leak. 

[kenzie]

stock ones, like right from honda?

[Jonesy]

Use brand new ones from Honda. I very lightly coated the edges with Permatex non-hardening gasket sealer (the stuff that looks like baby poo) and torqued the cam towers down to spec. Hasn't leaked a drop.

The main areas not to use sealer around are the o-ring seals for the main oil supply lines that run along the 2 innermost rear cylinder studs. If any sealer oozes into these galleries it will be carried up to the tiny orifices in the cam towers and plug them, starving the valvetrain for oil. The rubber pucks we're talking about don't have any oil around them being transported to a critical location. There are separate O-rings between the head and the cam towers that keep the pressurized oil contained.

[oldfart]

stock ones, like right from honda?

Yes, they are still available, though spendy, part number 12115-300-000 I think.  I just bought some.  In my view the aftermarket kits have poor quality rubber items. 

[kenzie]

Your right! I am going to get the proper ones from Honda, probably much better than having leaks and having to start over again! thanks for the advice