Yanmar 3JH3E clutch slipping

Gary Ryan

Gary Ryan

.
Sep 11, 2019
165
Hunter 386 Lake St. Clair
Hey Guys, our Hunter 386 has started to exhibit some intermittent clutch slippage. Backing out of a marina yesterday....put gear into neutral...then forward. Continued to drive in reverse. Put back into neutral then increase rpms into forward and it finally caught. Clunk sound. It's happened a couple times now. A hair raising experience going in reverse when you want forward. I did change the fluid out of the transmission this year, as the previous owner had put in the wrong type. Any thoughts would be appreciated.
 
jviss

jviss

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Feb 5, 2004
6,748
Tartan 3800 20 Westport, MA
What gear? What was the wrong fluid, and what's the correct fluid?
 
Ralph Johnstone

Ralph Johnstone

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Jan 4, 2006
6,491
Hunter 310 West Vancouver, B.C.
Gary Ryan said:
I did change the fluid out of the transmission this year, as the previous owner had put in the wrong type. Any thoughts would be appreciated.
Click to expand
Let's do an analysis of this problem rather than running around in circles shall we ?

First, answer all the above questions to the best of your knowledge. Test out @kloudie1 's questions by removing the shifter cable and shift the lever by hand (with the engine running) and report back.

It doesn't matter how much we, as a group, know about engines, without specific information we can't even guess what's happened and neither can you.

PS what engine, how many running hours, shifting (idle) RPM, how many running hours have YOU put on the engine ?
 
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Gary Ryan

Gary Ryan

.
Sep 11, 2019
165
Hunter 386 Lake St. Clair
I will follow up. I do like the idea of removing the cables and trying by hand. My transmission is a KANZAKI KM3P4. Reading prior posts on the list, there is a label on the transmission indicating the type of oil. The gentlemen before me used ATF. The label on the Gearbox says SAE20/30. I swapped out the oil out about a month ago after the first occurrence of the shifting issue. I hope to be back later this week where I'll grab more intel. Thanks for the responses.
 
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D

dlochner

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Jan 11, 2014
11,436
Sabre 362 113 Fair Haven, NY
Gary Ryan said:
I will follow up. I do like the idea of removing the cables and trying by hand. My transmission is a KANZAKI KM3P4. Reading prior posts on the list, there is a label on the transmission indicating the type of oil. The gentlemen before me used ATF. The label on the Gearbox says SAE20/30. I swapped out the oil out about a month ago after the first occurrence of the shifting issue. I hope to be back later this week where I'll grab more intel. Thanks for the responses.
Click to expand
Pull the transmission and get it rebuilt before you do any damage. ATF is slippery than oil. It will allow the clutch cones to slip and wear. Worn clutches will cause the problem you are describing.
 
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Gary Ryan

Gary Ryan

.
Sep 11, 2019
165
Hunter 386 Lake St. Clair
Here's where I'm at. Have approx. 1200 miles on engine. Checked the Morse MV throttle control. Verified cables are moving properly when going into Forward, Neutral and Reverse. Noted that when going into Reverse, Engine RPM's are approx. 1100 rpm after gear is set. When going into forward, RPM's are about 2000 for Forward gear to take effect. This exhibits a clunking sound.
 
D

dlochner

.
Jan 11, 2014
11,436
Sabre 362 113 Fair Haven, NY
Gary Ryan said:
Here's where I'm at. Have approx. 1200 miles on engine. Checked the Morse MV throttle control. Verified cables are moving properly when going into Forward, Neutral and Reverse. Noted that when going into Reverse, Engine RPM's are approx. 1100 rpm after gear is set. When going into forward, RPM's are about 2000 for Forward gear to take effect. This exhibits a clunking sound.
Click to expand
The damage was done with the wrong transmission oil. It needs to be rebuilt or replaced.
 
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jon hansen

jon hansen

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May 25, 2012
4,335
john alden caravelle 42 sturgeon bay, wis

Yanmar Diesel Motor Repairs in Detroit MI

Yanmar Diesel Motor Repairs in Detroit Michigan? Call Blue Water Marine Inc at (586)468-6960 ... We repair boat engines, stern drives and outboard motors
www.blue-water-marine.com www.blue-water-marine.com

prolly walking distance from your boat or dingy ride
 
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Gary Ryan

Gary Ryan

.
Sep 11, 2019
165
Hunter 386 Lake St. Clair
Thanks Dave. I have a shout out to a local Yanmar repair guy to see if he can come by and confirm. Bummer if it is.
 
Gary Ryan

Gary Ryan

.
Sep 11, 2019
165
Hunter 386 Lake St. Clair
jon hansen said:

Yanmar Diesel Motor Repairs in Detroit MI

Yanmar Diesel Motor Repairs in Detroit Michigan? Call Blue Water Marine Inc at (586)468-6960 ... We repair boat engines, stern drives and outboard motors
www.blue-water-marine.com www.blue-water-marine.com

prolly walking distance from your boat or dingy ride
Click to expand
Hey Jon, thanks for the input at the Service group! I put a shout out to them as well. Appreciate it
 
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Gary Ryan

Gary Ryan

.
Sep 11, 2019
165
Hunter 386 Lake St. Clair
Just a follow up. Although it's not my model of transmission, Daniel Fong goes through a good tear down of the Kanzaki system....
Youtube video may help others having issues.....
 
kloudie1

kloudie1

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Nov 6, 2006
9,894
Hunter 34 Mandeville Louisiana
Note that the one he is working is a "KM" series.. cone clutches. (motor oil for lube)
The "KBW" series have multi-plate clutches.. (auto trans fluid for lube)
Verify yours from the model number on the mfg plate affixed to the box.
 
Gary Ryan

Gary Ryan

.
Sep 11, 2019
165
Hunter 386 Lake St. Clair
kloudie1 said:
Note that the one he is working is a "KM" series.. cone clutches. (motor oil for lube)
The "KBW" series have multi-plate clutches.. (auto trans fluid for lube)
Verify yours from the model number on the mfg plate affixed to the box.
Click to expand
My transmission is a KANZAKI KM3P4. Reading prior posts on the list, there is a label on the transmission indicating the type of oil. The gentlemen before me used ATF. The label on the Gearbox says SAE20/30. I swapped out the oil out about a month ago after the first occurrence of the shifting issue.
 
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Gary Ryan

Gary Ryan

.
Sep 11, 2019
165
Hunter 386 Lake St. Clair
I talked with local Yanmar service here ( St. Clair Shores, Lake St. Clair MI). They are backed up 6 weeks. Got some good intel to try out. In addition reaffirmed the suggestion from Ralph Johnstone. Thanks Ralph and to everyone else! Hope to make it back there soon to try out. Speaking with their service guy, lends me to believe it is the Cone in the transmission. He suggested to try and get through the summer and then pull the transmission in the fall when on the hard. He suggested the company, "Shifting Gears" would be able to work on it. I'd like to give it a shot, but don't have access to a shop or a good vice. Anyhow, do you know if I can decouple the Kanzaki trans without shifting the propeller shaft back? I'll study it this weekend. If I can remove the trans myself, then I could drop it off and they could work on it at their own leasure.
 
D

dlochner

.
Jan 11, 2014
11,436
Sabre 362 113 Fair Haven, NY
Gary Ryan said:
Anyhow, do you know if I can decouple the Kanzaki trans without shifting the propeller shaft back? I'll study it this weekend. If I can remove the trans myself, then I could drop it off and they could work on it at their own leasure.
Click to expand
Most likely the shaft will have to move back an inch or maybe 2. Really depends on how much room there is. The good news is, it shouldn't be necessary to remove the flange from the shaft.

Removing the transmission is pretty simple, if you can get to all the bolts, remove the flange, remove the cable, remove the 6 or 8 bolts holding the transmission to the engine, slide transmission back and lift out. Reverse the process to reinstall.

When I removed the transmission from my not-a-Hunter, 2 bolts were not accessible, so the engine had to be lifted about 3 inches.

Call the transmission guys see if they can service it faster if you bring it to them. Both times I've had transmissions rebuilt the turnaround time was less than a week. Once opened up, the transmissions are pretty simple, should only take a couple of hours to tear it apart and rebuild it, if they can get the parts.
 
Gary Ryan

Gary Ryan

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Sep 11, 2019
165
Hunter 386 Lake St. Clair
Thanks Dave. I believe the bolts are easy to get to. I will call the transmission place tomorrow. Thanks for the quick update!
 
Gary Ryan

Gary Ryan

.
Sep 11, 2019
165
Hunter 386 Lake St. Clair
Just wanted to follow up. While at the boat yesterday, my sailboat broker was working on another boat trying to get a stuck sail unfurled. I gave him a hand. He came over to my boat after and we verified that the Gear/throttle cables are working fine. Long story short, we pulled the cables off the engine and worked on it there. Result, the clunking and dropping into gear is indeed inside the transmission. So, I'm now on the hunt for a repair shop or replacement. Thanks to everyone for their input!
 
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jviss

jviss

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Feb 5, 2004
6,748
Tartan 3800 20 Westport, MA
You are fortunate that parts are available for these. My gear is from a defunct company and none of the wear parts are available any more. :(
 
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