Problem turning engine over - cant start - help
Posted March 30, 2002 - 09:19 PM
I ran into a mechanical problem this weekend for the first time with my 98 WR400 engine. I thought I would see if anyone else has expereinced this before I start diagnostic surgery.
Bike has been running great, no probs. While riding this weekend we stopped at a trail crossroads to decide what way to go and I shut the bike off. I then restarted it, put it in gear and proceeded to take off and as I let the clutch out I stalled it, or at least I think I did. After that I couldnt restart it... better yet I cant kick it thru a complete revolution.
As you go down with the kicker it turns over a bit and then makes a light metalic clink and will not turn over any more. putting the bike and gear and backing up a tiny bit you can feel the engine turn backwards a bit (I know this is bad to rotate it backwards cause of timing chain jump possibility). you can then proceed to kick it a bit until you hit that "spot". You can also feel this spot by doing the same thing in gear, roll back a bit then forward and it hits it.
The one thing that seems a bit odd is the compression release lever doesnt seem to have as much tension on it, almost as if internally it is still released, however the external actuator on the head is moving its full range of motion.
Has anyone experienced anything like this and could save me some time exploring? I havent found anything else on the board that describes this situation.
Posted March 31, 2002 - 05:12 AM
Posted March 31, 2002 - 08:54 AM
Posted March 31, 2002 - 09:37 AM
[ March 31, 2002: Message edited by: Chaindrive ]
Posted March 31, 2002 - 05:01 PM
Posted March 31, 2002 - 05:29 PM
Posted March 31, 2002 - 06:26 PM
Posted March 31, 2002 - 08:26 PM
I havent tried to turn the engine over back wards until it hits that spot, so I dont know about the rod possibility. I have had rods break before on a running engine and you defintely heard it, there was no noise accompanying the "stall".
Will be interesting to see what it is... maybe even something in the tranny?? but the wierd feel of the compression release I guess points to valvetrain (unless of course that wierd feel is just me).
And to think I went four stroke for reliability!
Posted April 01, 2002 - 01:35 PM
[ April 01, 2002: Message edited by: freestyle111 ]
Posted April 11, 2002 - 12:10 PM
Posted April 11, 2002 - 03:59 PM
I had tightened up the slack in the compression release cable before riding and after a very short period of time the bike locked up very similar to what you are talking about.
Because it was a new bike and just slightly out of warranty Yamaha was willing to take care of it. It only took a month to get the back ordered new head. The service manager admitted to me that he heard from Yamaha there was a clearance problem on the first few heads that came out and they determined that was the problem. Apparently at that time there had been 15-20 bikes that had suffered that same problem. I never told him that I had taken the slack out of the compression release cable. Truth is, I didn't realize or even consider that to be the problem at the time. Soon after I got the bike back there was a tech update released on leaving slack in the cable.
Maybe you can use that angle with the dealer if it turnes out to be the exhaust valve. ( that is also my bet by the way.