Hey guys new here and I gotta question for y’all I gotta 05 grizzly 660 that I bought and it smoked really bad, the rings were waxed in it, so I put a new jug and piston in it and replaced all the gaskets runs great. The issue is it’s POURING oil from behind the banjo bolt at the top of we’re the crankcase is. It leaks like 3 cups of oil in 2 seconds of idling. I thought maybe the gasket tore when I put it together so I tore it back down replaced the gaskets and put new crush washers on the banjo bolts. I understand these engines have a tendency to crack we’re the cylinder bolts to the crankcase, could that be what I’m dealing with? Any help would be great thanks.

 

Don't know that model at all, but if it is pouring that much out any cracks would be very visible. Check the banjo union itself. I have known them to crack. double check for dirt between washers, case and banjo. Some Yams have a tubular rubber dowel like thing between crankcase and cylinder, to seal the main oil gallery, have you left it off?

 

Are you referring to the o ring that is around the cylinder on the jug? If so I replaced that, it’s pooling so fast I can’t pin point the exact place of the leak. I will check the bolt it’s self to be sure. Thank you

 

Clean round that area with solvent so it is nice and dry, then spin the engine on the starter with plug out, and watch where oil starts to damp from. Checked the parts book and it doesn't look like the 660 has that oil seal/dowel, which is used on the smaller models.

 

looks like it blew the base gasket out once again. I have no idea what’s going on! I took the oil tubes off cleaned it real good and got this image with my endoscope