Yanmar Transmission Issues?

[Xanthan Echo]

HI I'm looking at an 85 Hunter 31. Overall well taken care of and in good shape.

It has a 16HP Yanmar which looks very clean.

The owner says the engine when cold takes awhile to engage when put into forward. 10-15 seconds. Reverse is fine right away. And forward is fine after "warmed up"

To me this sounds like a major transmission issue only likely to get worse.
He doesn't seem to think it's a big deal.

Is this just a yanmar quirk? Or should I be looking elsewhere?

Thanks.

[ozsailer]

Just to clarify - are we talking saildrive or direct shaft drive. If saildrive I would suggest a service to the drive cones. Easy job for any mechanic.

[A la carte]

"Is this just a yanmar quirk?"

My 50hp Yanmar engages F & R instantly. Different engine and transmission than yours of course.

[Xanthan Echo]

Originally Posted by ozsailer

Just to clarify - are we talking saildrive or direct shaft drive. If saildrive I would suggest a service to the drive cones. Easy job for any mechanic.

Direct Drive

[Wotname]

Originally Posted by Xanthan Echo

HI I'm looking at an 85 Hunter 31. Overall well taken care of and in good shape.

It has a 16HP Yanmar which looks very clean.

The owner says the engine when cold takes awhile to engage when put into forward. 10-15 seconds. Reverse is fine right away. And forward is fine after "warmed up"

To me this sounds like a major transmission issue only likely to get worse.
He doesn't seem to think it's a big deal.

Is this just a yanmar quirk? Or should I be looking elsewhere?

Thanks.

It isn't a Yanmar quirk. They should (and do) shift immediately, cold or warm.

It needs fixing, it will only get worse (unsurprisingly). Likely to get worse rapidly.

Maybe only need the cone clutch lapped but maybe be more serious.

[lockie]

Highly likely it is not the end of the world, but just part of the normal life-cycle for these Kanzaki KM and KP series cone-clutch transmissions. They will naturally develop some slip over the years, which will get progressively worse. If you are pretty handy, pulling the transmission, disassembling it, lapping the cones and putting it all back together will not be beyond you. Search for Yanmar and/or Kanzaki cone lapping. I can help with pdf of workshop manual if you need, just pm me. Plenty of threads out there both here and elsewhere.

If you are in a pickle where it just won't engage at all, a push on the shift lever on the gearbox can help, but you need to fix it licketty-split if it's taking as long as you say.

If it's any consolation, these boxes are very robust. Mine ran with a mix of sea-water and oil for a year or so after I bought it. I didn't get around to properly refurbing it for another couple of years, and then new bearings and seals made it good as new. They can take a lickin' and come up tickin'.

Cheers, Graeme

[Hesti]

If you are lucky - it is just filled with the wrong oil and a change to the correct oil will set it right.



If you are not lucky - it will need to be opened and sorted out.

[AndyBC]

I have a 91 Hunter 28, I think it may be the same engine/transmission as the 85 Hunter 31 (2GM20F with Kanzaki KM2P). Mine engages F and R right away, even when cold.

Is this transmission issue a showstopper for the purchase, or are you thinking of getting a discount on the price or have the owner fix it?

Originally Posted by Xanthan Echo

HI I'm looking at an 85 Hunter 31. Overall well taken care of and in good shape.

It has a 16HP Yanmar which looks very clean.

The owner says the engine when cold takes awhile to engage when put into forward. 10-15 seconds. Reverse is fine right away. And forward is fine after "warmed up"

To me this sounds like a major transmission issue only likely to get worse.
He doesn't seem to think it's a big deal.

Is this just a yanmar quirk? Or should I be looking elsewhere?

Thanks.

[lockie]

Originally Posted by AndyBC

I have a 91 Hunter 28, I think it may be the same engine/transmission as the 85 Hunter 31 (2GM20F with Kanzaki KM2P). Mine engages F and R right away, even when cold.

Is this transmission issue a showstopper for the purchase, or are you thinking of getting a discount on the price or have the owner fix it?

I'd suggest getting a quote from your local marine diesel fella for a deglaze &/or refurb and using that in your negotiations. Then RTFM, do it yourself, buy yourself a nice present with the savings, and bask in the knowledge that you no longer fear your transmission........