KBW20 marine gear not engaging

[mhansen]

My Halberg Rassey 35 Ketch has a Yanmar 4JHE with a KBW20 marine gear that has recently starting having issues engaging in "forward" (reverse seems to work fine). The gear doesn't seem to "slip" in/out of gear once it is engaged (I ran it for a couple hours this past weekend with no issues once I got it in gear), the issue is actually engaging into forward.

I feel like this is a "linkage" issue but unfortunately I can't do any more troubleshooting until the weekend. My plan is to disconnect the linkage at gearbox and see if it engages with any problems from the gearbox input levers.......

Looking for insights from anyone who has had similar issues.
Mike

[aduke]

I have very recently encountered a very similar problem on my Hunter Legend 40 with the KBW20 tranny. Only thing is I could not get it out of reverse.
Disconnected the linkage and could not get it it from reverse. Ended up pulling the transmission.
Now to find a good re-builder local and not taking the rest of the season.

[Bill Seal]

Check with Sound Marine in CT. I know nothing about him, I was going to buy a Volvo trans from him until I found one locally.

[TheOffice]

I can sell you a core

[aduke]

Thanks Bill. Will look them up!

[mhansen]

I'll be down in the engine compartment this weekend pulling mine..... should be sailing....

[boatbod]

Cone drive transmissions are relatively easy to repair yourself - most times you don't need parts, just lap the cones to remove the glaze and allow them to lock together.

[four winds]

Mhansen, removing the linkage to manually check shifting is a good idea. Should tell you what you need to know.

The manual has some very specific geometry requirements for the linkage to function. And you should have good solid detents in all positions.

If it works well with removed, then ensure this goemetry and solid feel remains after the cable is returned to service.

Could be just a small adjustment of the cable at the trans, or maybe a new cable. Hopefully not a trans issue, but it could be just the shifter assembly in the trans. Which is easy to remove and service.

[four winds]

Originally Posted by mhansen

I'll be down in the engine compartment this weekend pulling mine..... should be sailing....

You have determined it must be pulled?

Your original post sure seemed like the cable and shifter assembly issue that I had to correct when I purchased my boat.

[boatbod]

I thoroughly agree that you should check the shifter with the cable disconnected, but I will note that there is nothing you can do to the shifter mechanism itself. If a cone transmission doesn't engage it's because the cone isn't grabbing.

[four winds]

Unless the throw is restricted and it's not engaging the detent fully. Or the shifter pawl has excessive wear.

But I agree if the helical grooves on the mainshaft are contacted by the cone then it should force it into the gear from the torque.
It's just that the first post indicated trouble engaging and good operation once engaged. Took that to mean no slip.

For what it's worth, my Edson pedestal retained its long throw linkage for the A4 even after the change to the Yanmar/Kanzaki setup. Which wrecked havoc on the short throw geometry of the new shifter mechanism.

Had to rebuild the shifter, new cable, and mod the Edson lever to set it right.

[boatbod]

Usually the cone clutches will grab if they contract, but not always. Sometimes they continue to slip until you rev the engine. For some reason Yanmar sail drives are more prone to this than the equivalent regular Kanzaki transmissions, but it does happen and the fix is usually the same. Take apart and either replace or lap the mating surfaces.

[LeaseOnLife]

The KBW20 has no cones, it uses clutches. If clutches are burned up, the oil (ATF) will smell burned and is brown/black instead of bright red. I agree on checking the shift control for full engagement first.

Dirk

[four winds]

Leaseonlife, lol, well that thar will make a difference. :-)

I thought I remembered the original post mentioning cones, and not just a subsequent post. So I didn't look it up as usual.

So......nevermind.... here's my sign.

[boatbod]

indeed
Well anyway, if you ever need to fix a cone transmission....

This one I suppose will be needing a new clutch pack.