G1800 Engine Oil Leak at Front

[Kubota3710]

have a Kubota G1800 spewing oil from the front of the engine (16 HP Kubota D662 diesel engine). Hard to see where the leak is from as pulleys and flywheel is in the way. I have pulled the PTO pully and flywheel to be able to see. In the center of the picture is the front of the crankshaft (five bolt holes). Just around that is a black "Seal Oil part 09560-00007" Outside of that is the Cover for the bearing case (16 bolts). The bearing case cover has a gasket under it.

Question: I am trying to figure out should I just replace the Oil Seal Part, or is their a possibility that the leak is from the gasket of the bearing case cover. I don't want to remove and replace more parts than I have to. I've never looked under a bearing case on the front of a crankshaft on any engine, so insight from others would be helpful.


Thanks, Rich

 

[lugbolt]

that seal appears to be pushed out

replace it

while you're replacing it give the area a good cleaning. Look closely at the crankshaft. Does it have any groove in the crankshaft where the seal lip rides? IF so, see if they have a kit to address it which is usually a different seal with a sleeve that is pressed onto the crankshaft, and it's a bear to install (the sleeve is). If no groove, you will want to look very closely at the crankcase vent. It comes off of the valve cover, to a hose, and the hose runs down the side of the engine to atmosphere down by the oil pan somewhere. It just goes to nothing. If that hose gets plugged, or the vent in the valve cover becomes restricted, it will do just exactly what I think I see in the pic-push the seal out. So yes I'd just pull the valve cover (easy on those mowers), clear out the vent, and address the tube before even beginning to replace the seal, so you don't forget to address it after the fact. If you do forget, it'll just push another seal out so you can do the same job again.

I haven't seen it on the G series but on some engines I've seen poor or contaminated engine oil cause the seals to shrink and/or soften up and basically fall out. Very uncommon but it's happened.

 

[Kubota3710]

Thanks, great response. That all makes sense. I am not at the lawn tractor now, but I have seen the vent hose you are talking about. I am waiting for the seal from Messicks and will get back in a week or so with what I found.