- Mon Aug 15, 2022 9:17 am
Short remainder, the 1959 model has just atmospheric outlet on the left side of the crankcase, just below the cylinder. The 1960 model has outlet in the same place but with two ring/plates operating as one way valve and the small diameter pipe connected back to the oil tank, additionally there is breather in the crankshaft nut connected to the chaincase.
I do have 1959 bike but with 1960 setup.
I did experience increase in overpressure in the chaincase manifesting with lots of oil coming out from the chaincase breather hose.
So I followed advice from certain Constellation owner and blocked off the breather nut. Wrong advice. Don’t do it.
I am old but did a rookie mistake. Mixed two different solutions from different years. Closing off the breather nut perhaps works well with atmospheric outlet. Not with these two tiny valve plates. As a result I have now oil weeping from under cylinders. Suspect crankcase pressure damaged the paper seals.
And with hindsight I suspect original reason for overpressure was one of the plates in the side breather got skewed and didn’t work properly. With engine working amount of overpressure from the side pipe was negligible compared to same setup but with plates removed.