Tranny clunks when changing gear

[Kd9truck]

Hi all, I have Yanmar transmission KM :35P and a Yanmar 4jh5e motor pushing my Jeanneau 44i, when I change gears, neutral to drive,or drive to neutral, or neutral to reverse it clunks, I am thinking it is the damper disc does anyone have similar experiences.

[rbk]

Think you’ve figured it out. Prob a broken spring or two. Only one way to know for sure.

[Cheechako]

or idle rpm too high.

[rbk]

Originally Posted by Cheechako

or idle rpm too high.

Cause and effect?

[Kd9truck]

I would say RPMs sometimes, I am sure we could all be guilty of that, but this is happening at the factory spec idol speed.

[rotrax]

If you saw inside one of those transmissions and saw the size of the bits whizzing round, stopping and changing the direction of those will cause a clonk.


We have a 4JH4-HTE.


We pause between changes.


Helps a bit, but does not alleviate it.

[AKA-None]

Originally Posted by rotrax

If you saw inside one of those transmissions and saw the size of the bits whizzing round, stopping and changing the direction of those will cause a clonk.


We have a 4JH4-HTE.


We pause between changes.


Helps a bit, but does not alleviate it.

This
For virtually all transmissions

[JPA Cate]

If you have a folding prop, the clunk may be from the blades opening up. Ours (Flexofold) clunk. In our case it isn't the tranny. But shaft drive, too, so if you have a saildrive, goodness only knows what's going on in there!

Ann

[Kd9truck]

Ok, I am not “power shifting”, or doing “hole drops” the clunk is not the normal sound of the transmission going into gear it’s louder Than a normal gear shift.
Thanks all

[lhuff35204]

I have the same issue on my 4JH4-HTE. I pause between shifts, but emergencies like kayakers paddling into the channel in front of you cause the engine to stall. I've tried to get this looked at but have never been anywhere long enough (6 months) to get on a Yanmar service list.

[Stewie12]

A pause in neutral when changing gear is essential to avoid damage.

[Kd9truck]

Originally Posted by lhuff35204

I have the same issue on my 4JH4-HTE. I pause between shifts, but emergencies like kayakers paddling into the channel in front of you cause the engine to stall. I've tried to get this looked at but have never been anywhere long enough (6 months) to get on a Yanmar service list.

Yes to those instances where speed is needed to react to some one who does not understand the physics of objects in motion and the unintended consequences of the situationally ignorant. Your stalling sounds like your idle is set to low, I would goggle that it should not be hard to adjust, it could also be the engine was cold? But there are other reasons for stalling.
They are great motors, very low maintenance, the launches run with them all season 2500 hrs a year, they do rebuilds every 10k hrs. They are presently running a motor with 3 rebuilds and it’s a year away from its 4th.