PRM120 Gearbox

[adagio]

My PRM120 gearbox has started blowing oil out of the breather hole when we are cruising. As far as I can see the more power from the engine the more oil is blown out. We are talking a few millilitres each time. The oil level in the box is where it should be and not overfilled. With engine stopped and the gearbox cleaned of all oil there are no leaks. Running the boat at slow speed and with a cloth around the breather (very temporary) there are no other visible leaks.

 

Suggestions pleased.

[Tiggs]

Difficult to see what this might be, although a clue might be in the name of item 13 "Valve, breather" which implies that there is a spring valve in it which might have failed. Suggest replacing the breather itself before anything more drastic.

 

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