Topic: Leaking oil, but from where?

[JHansen]

In the midst of trying to synch my carbs and play with adjustments, I have developed a strange oil leak in the barrels of my cb400.

With the bike on it's sidestand, I have a small amount of oil seeping out from the opening on the rear side of the barrels. It is the opening in the center where you can see the cylinder head stud. The oil is coming out and running down the 4th and 5th fin, all other fins are dry. The stud appears wet with oil as well, but this is nowhere near either the barrel or head gasket, both of which are bone dry. Where is this oil coming from? Thoughts? I've been running a fan on the motor to try and prevent any overheating, hope I havent messed anything

Motor have 55 break-in miles so far. leak just developed. Help!!!

John

[supersport_CB400F]

Did you fit all the sealing washers # 242 marked yellow?

[JHansen]

Oh boy-

No, no sealing washers on those two bolts. I replaced those sealing washers in the same locations where they came from during disassembly.

Crap... seems like an easy fix, but only if I can get to it without pulling the motor.

Can I get to all the head bolts and re torque them all without pulling the motor? I think I can. Am I wrong?

What about a thin bead of Hondabond around those bolts (after cleaning both the bolt and mating surface in solvent) if I am unable to locate more sealing washers- any concerns?

Sigh of relief, I was thinking the problem was something worse!

Thanks Biffta!

[supersport_CB400F]

You should be able to fix the problem with the engine in the frame, but the sealing washers are odd they wrap around the stud so it’s probably better if you can find some. 

Dave