Kanzaki KM2-P gearbox
- Thread starter Ken13559
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It's got a "Mechanical parallel servo cone clutch", I really don't know what that means but I'd stick to straight motor oil Ken, or as Yanmar calls it "marine gear oil".
http://www.yanmar.es/theme/yanmares/uploadedFiles/engine_files/Gears/outline KM2P-1.pdf
http://www.yanmar.es/theme/yanmares/uploadedFiles/engine_files/Gears/outline KM2P-1.pdf
Transmission Schematic
Ken, Attached is a diagram of how your transmission works. This is not your specific transmission, but yours is made and functions the same way. The cone clutches inside are what transmit the power to the output shaft. Basically a male bronze cone which pushes into a steel female cone which is machined onto the backside of the gear. In a nutshell, you depend on the friction in the cone clutches to transmit the engine power. Putting something like STP may increase the slippery-ness enough to cause the cones to slip .. that would overheat the cones and cause some problems which would eventually fail the transmission. I wouldn't do it.. as others have said, use straight grade 30 motor oil in it ..
When the engine is running, all the gears are spinning .. in neutral, the output gears are spinning on the stationary output shaft..The shift cone is stationary. When you put it into "Forward" the drive cone moves into the recess of the left side gear and begins to slip slightly as it contacts the gear; the spiral thread under the cone pushes the moving cone harder into the gear cone until it does not slip. The gear and the cone are then turning at the same speed, driving the output shaft..
You can see from the right hand drawing of the drive cone that it has grooves .. Those grooves are designed to channel the oil away from the contacting surfaces so that they don't slip while driving.. heavier oil or oil with more "slickity" may not let the cones lock together properly..
Ken, Attached is a diagram of how your transmission works. This is not your specific transmission, but yours is made and functions the same way. The cone clutches inside are what transmit the power to the output shaft. Basically a male bronze cone which pushes into a steel female cone which is machined onto the backside of the gear. In a nutshell, you depend on the friction in the cone clutches to transmit the engine power. Putting something like STP may increase the slippery-ness enough to cause the cones to slip .. that would overheat the cones and cause some problems which would eventually fail the transmission. I wouldn't do it.. as others have said, use straight grade 30 motor oil in it ..
When the engine is running, all the gears are spinning .. in neutral, the output gears are spinning on the stationary output shaft..The shift cone is stationary. When you put it into "Forward" the drive cone moves into the recess of the left side gear and begins to slip slightly as it contacts the gear; the spiral thread under the cone pushes the moving cone harder into the gear cone until it does not slip. The gear and the cone are then turning at the same speed, driving the output shaft..
You can see from the right hand drawing of the drive cone that it has grooves .. Those grooves are designed to channel the oil away from the contacting surfaces so that they don't slip while driving.. heavier oil or oil with more "slickity" may not let the cones lock together properly..
I go along with what Ted and kloudie say. A few years back, I thought I was doing right by using "transmission" oil even though the literature clearly said use grade 30 motor oil. A year later I had my KM2-A re-built because the cone wasn't engaging consistently.
Prior to using the transmission oil, I thought the engagement was a little "rough" at times and there were a few occasions when I would shift into gear at idle and it wouldn't engage until I throttled up a litte. It also took a little time for Sue to realize that after warming the engine with slightly higher than idle rpm's means that you have to back down to idle before shifting. I tried explaining to her that she doesn't shift the car into gear when she has her foot pressed on the gas, but it took some time to register ... and the tranny took some abuse in the process.
After I used the transmission oil, the symptoms definitely worsened, and I decided to re-build. It wasn't cheap, that's for sure. I took it to Mack Boring and it was north of $600 if I remember correctly.
Actually, I think it would be a good idea to have a lock-out button that prevents anyone from shifting into gear from anything other than idle. It's standard on power boats so I would think it could be a standard feature.
After I used the transmission oil, the symptoms definitely worsened, and I decided to re-build. It wasn't cheap, that's for sure. I took it to Mack Boring and it was north of $600 if I remember correctly.
Actually, I think it would be a good idea to have a lock-out button that prevents anyone from shifting into gear from anything other than idle. It's standard on power boats so I would think it could be a standard feature.
Scott, sound like you have separate throttle and gear shift. That reminds me, a hired skipper wreck my friend's gearbox on her 38footer power boat. Engine was still running forward and the hired skipper just geared it into reverse. Whoa! Smashed the gears. Plenty ouch!
Ok back to my gearbox, each time after several days, i get grinding noise whenever i put to forward or reverse. But if i run it at a little higher rpm, the noise goes away for the day. But i have to do it for both fwd and reverse. Some said its due to barnacle growth in shaft log and cutlass. I hope its not the gearbox.
Ok back to my gearbox, each time after several days, i get grinding noise whenever i put to forward or reverse. But if i run it at a little higher rpm, the noise goes away for the day. But i have to do it for both fwd and reverse. Some said its due to barnacle growth in shaft log and cutlass. I hope its not the gearbox.
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