Oil in u joint bellows

[dave 7 0]

Hi Guys. Recently removed my stern drive (alpha 1 gen 2 ) to replace the water pump and i noticed oil in the u joint bellows. The boat had been loosing oil from the monitor since ive owned it. I checked all the hoses and fittings from the monitor bottle to the fitting in the transom and found no leaks. the missing oil would always end up in the bilge. I'm assuming it was somehow leaking into the u joint bellows and then into the bilge. on the driveshaft right behind the splines there is an oring. Right before the u joint yoke there are what appears to be two oring grooves about 1\2"apart but they did not have any orings in them.Are there suppose to be? thanks in advance. boat is 98 bayliner Capri 1950 with a 3.0 if that makes a difference

 

[Bondo]

Right before the u joint yoke there are what appears to be two oring grooves about 1\2"apart but they did not have any orings in them.

Ayuh,.... Those 2 o-rings lock the shaft to the gimbal bearing,.....

If yer gettin' oil in the bellows, it's comin' from the drive, through the seal, where the input shaft goes into the drive,......

 

[dave 7 0]

OK thanks for the info. So the input shaft seal will leak even when sitting idle? All the oil loss from the monitor tank happens while the engine is not running. Since I've bought the boat I've never had it in the water.

 

[tpenfield]

Yes, oil in the u-joint bellows is a typical sign of the drive shaft seal leaking. The more worn the seal is, the more it will leak, so the symptoms that you are seeing may be telling the story.