Results 1 to 4 of 4
  1. #1

    1991 Yamaha 650 Driveline repair need help!

    I somewhat inherited a 1991 Yamaha 650. Atleast thats what year I believe it to be. I'll attach a pic. Well she starts up and runs fine, but she wont go anywhere. It makes all kinds of noise too. We sort of tracked it down to the driveline. The shaft coming straight off the motor spins fine, then goes into that little box in the firewall and attatches? to the other shaft that runs to the prop. Well at some point in that box, it is either stripped or broken because you can start it up and hold the shaft to the prop and it wont move. You can also freely turn it with your hand when the motor is off. Is it snapped or stripped, I don't now how these 2 shafts are connected inside that box. Any help would be great! Thanks!Click image for larger version. 

Name:	IMG_5784.jpg 
Views:	86 
Size:	100.0 KB 
ID:	274787

  2. #2
    lukejaeger1's Avatar
    Join Date
    Jul 2011
    That sure is a good lookling machine for a 91!! I don't know much about these but I would think there would be a coupler in there. Just take the box apart and see what you find.

  3. #3
    Old Ski Insanity w/rpm500's Avatar
    Join Date
    Aug 2005
    Crystal River Fl
    my guess ,spline is stripped out ..if the safety cover is removed from the inside you can verify that the intermediate shaft is moving.. if the rubber coupler were bad, it would still turn the impeller ,just be very noisy.. you must take out the pump and housing to inspect the spline on the 2nd shaft..if this is good, then the motor must be moved forward to remove and inspect the intermediate assembly for stripped splines in the female end... if the motor runs and nothing turns there is a good chance that one half of your coupler is broke off.. Also check for broke or loose engine mounts, as this puts undue side load on the coupler...

  4. #4
    Brabender's Avatar
    Join Date
    May 2012
    Long Island, NY
    I'm thinking broken coupler, i doubt the splines stripped

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. 2000 Yamaha SUV Project: newbie needs help
    By jigeye in forum Yamaha Projects & Build Threads
    Replies: 9
    Last Post: 11-12-2010, 08:35 PM
  2. 2003 yamaha fx140 top speed..need help!
    By yamahaa in forum Yamaha PWC Performance (4-stroke)
    Replies: 7
    Last Post: 08-13-2010, 09:37 PM
  3. yamaha xlt 1200 (i need help)
    By bscg1 in forum Yamaha PWC Performance (2-stroke)
    Replies: 18
    Last Post: 06-03-2009, 08:32 PM
  4. WTB Driveshaft for 1991 yamaha 650
    By mikeoxbig in forum Yamaha Classifieds
    Replies: 4
    Last Post: 07-21-2008, 08:50 PM
  5. 94 GTX 650 in Aussie needs help.
    By Boris in forum 2-Stroke Performance
    Replies: 0
    Last Post: 02-16-2007, 12:13 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts