The International CBX Owners Association

Posted: **Mon Oct 20, 2003 3:08 pm**

My recently installed engine on my '79 runs well...the problem is an unseen oil leak behind the engine, above the cases. Both oil line connections (head and top of cases) are fine and tight. (Same with oil send unit) Overhead lines are fine. The amount of oil that ran off the top left side of the cases was enough to cover my left boot in an hour! No visible source of leak upon inspection run, ( with a fan blowing on the motor), and me taking it up to 4 grand!

How much oil could blow upward through the crankcase vent connection hose if it is looser than appears? I actually had a puddle on top of the cases! My '76 triumph never does this!

I am stumped? Any ideas? Tom R

Posted: **Mon Oct 20, 2003 3:41 pm**

A wet left boot from a leak "behind" the motor and above the cases? Do you have rear sets? When my left boot got oiled it was the crank end cover which is warped from the factory I think.

Took a new O ring and gasket and gasket goo to seal it...but its all better now. Can't imagine where (your) oil source is coming from?

Posted: **Tue Oct 21, 2003 6:20 pm**

Terry, i dusted the motor with powder to see where the oil originates. It appears to be leaking at the valve cover gasket and bleeding down the front...and bleeding down and back thru the openings in the cylinder heads....then down to the top of the cases, my foot, etc.

But I still got 250 miles in on a Chicago October weekend!