Yanmar YSM 12 jumps out of forward gear

[Nelson J]

I have a Yanmar YSM 12. It does fine in reverse, but in forward gear it jumps out. The linkage is ok, it has been checked. Has anyone ever experienced this before and if so what was the outcome?

 

[SvenH]

When you say "Linkage is ok" what do you mean? It can look ok but still be set incorrectly.

Have you tried disconnecting at the gearbox and then trying manual engaging/disengaging?

 

[charles_reed]

I have a Yanmar YSM 12. It does fine in reverse, but in forward gear it jumps out. The linkage is ok, it has been checked. Has anyone ever experienced this before and if so what was the outcome?

Yes, on a Yanmar 2GM. Jumping out of gear was how it started and it finally would not select forward at all.

It transpired that the selector fork had worn on the side operating forward gear. Taking it off and changing the way it faced cured the problem.