150hp 60* bearing

[reeldutch]

why is the lower crankbearing on this motor ventet?
the vent line go's to the vapor seperator.

 

[Faztbullet]

Re: 150hp 60* bearing

So the fuel does not puddle and cause the cylinder to fowl. All 60/90 degree loopers have a vented and recirc oils and some have a check valve/filter .

 

[Dhadley]

Re: 150hp 60* bearing

OMC's explanation was that the oil reflow system fed oil to the lower bearing and it was a dead end. That could, in theory, cause an air lock of sorts and actually stop oil flow from getting to the lower bearing. (Kind of like trying to fill a gearcase from the top hole) It was their reasoning for some lower main bearing failures.

The obvious questions was, why had it worked for so many years without the vent? We never really got an answer to that. We saw lower bearing failure before the vent and after. Most were related to water injestion, some weren't.

 

[reeldutch]

Re: 150hp 60* bearing

it does make sence to me.

i tought that the vapor pump only pumped up vapor
so its pumping oil from the lower bearing back in the vst?

or is it only getting rid of that trapped air?

 

[Dhadley]

Re: 150hp 60* bearing

According to them it's just a vent.