ATV Florida Forum

Guys, I need help! My 660 raptor started pumping oil up crankcase breather tube into air filter (a lot). It wont stop. I can't figure it out. Oil level is good, not high. I adjusted valves, checked compression, and checked all vent and breather tubes and all seems to be in spec. I've read of other people having this issue in this forum, but no results as to what the actual problem ended up being. Please somebody help!!!!!!!!!!!

you need to check your clutch basket, when your clutch basket starts to go they have been know to spit out a lot of aluminum, then there is a screen for your oil pickup that gets clogged with aluminum shavings from your clutch basket.  If your basket is in good condition you really need to check your screen.  In order to get to it you are going to have to take your whole motor apart.  I will see if I can find any more info on it.  Good luck!

http://www.raptorforum.com/forums/showthread.php?t=46745

this is a good read

Thanks for scaring the sh*t out of me. No, for real, I'll look into this later today or tomorrow. Sounds like a good posibility thats whats up. I'm pretty good at tinkerin' with things, but I've never split cases. I'll check oil line first and look at clutch and update you when I find something. Thanks for your help so far......

Well, good news and bad news. First off, I pulled bottom oil line off resivoir with screen and it was loaded with aluminum and black particles. I'm assuming aluminum is clutch basket and black particles are cluth plate. This is got to be the problem for sure. I havn't pulled cluch cover off to 100% confirm, cause I'm undecided on what to do. I'm not sure about spliting cases. I don't have case seperator tool and have no idea what else I will need. Thanks  IXIswamperIXI for all your insight. You da man. The link you gave me was great. Now just to decide if I can talk my self into trying or not. If I did, would I need new rings and what other parts would I might think about replacing why I was in there.

You dont need to split the cases to put a new clutch in, its not that big of a project.
  BUT, generaly when a motor is pushing oil out of the crankcase it is due to the top end being wore out and the compression is leaking past the piston and rings and pressurizing the crankcase which of course pushes the oil out the vent.
  How old is this machine? How and where riddden? Has it ever been sunk? What type of air filter do you use? What type of air filter oil do you use?

Thanks for the insight chillinthemost. I believe my problems run deeper than just clutch. The oil return line was clogged with shavings which means their in the motor and surely clogging my oil screen. Thats the direction I'm heading with everything. The quad is fairly new to me so I'm not sure history. Compession checked out by me and then Yamaha, I trust my self more. Uni foam filter. Thanks though and at the point motor is out split, oil screen replaced and motor cleaned, the cluth WILL be the easy part.