Are 3 cylinders better than 2?

[California]

I'm used to high rpm bike motors and car engines, where a change in bore size, even by fractions of a millimeter, is something to fret about, since it changes the balance of the reciprocating assembly. I guess the lower rpm and more durable lower end of these machines make it a non-issue.

So far as I know the recommended replacement for now-unobtainable YM1700 pistons and cylinders is to use the (larger diameter) YM2000 versions. No rebalance or anything, just slap them in and go. Tell this to a bike tuner and his hair would probably stand on end.

 

[Neat 1500]

mine is noisy but i wouldnt call it deafening,certainly my ears ring after slashing for a few hours straight but thats all in the fun of it . i will do some video footage of it and see how mine compares if i remember to take the camera with me

 

[shawnjvl]

I aimed my muffler forward like California and that makes thing a little quieter. I know my 2000 is a little loud, But about 1800 rpm is the sweet spot. It sounds smooth and pulls like crazy, I can bury my 5' box blade, and it just seems to pull harder and harder until I loose traction.
One other comment, I have used some other tractor brands (HST) and notice how loud the gear noise is. The gear box on my 2000 is very quite, or maybe I can't hear it over the motor.

 

[clemsonfor]

The 2000 may be louder than the 1700 cause there is more metal in the block around each piston! :laughing: Only fractions of an inch probably but more metal to deafen the sound?

 

[California]

I think you're on to something there. 1700's sleeves have same OD and smaller ID. That additional metal must help reduce the clank.

 

[Ginormous]

I remember that mine got quieter when I changed out a dirty fuel filter. The restricted flow was making it run rougher and more loudly.

 

[Car Doc]

No rebalance or anything, just slap them in and go. Tell this to a bike tuner and his hair would probably stand on end.

Chainsaw tuners are oblivious to reciprocating imbalance also........

There is no better feeling than holding a 16k rpm bomb apparently.

A 2600 rpm engine is a different story true.

 

[California]

...
However - the two cylinder tractors have an advantage that they are designed to be simpler and a lot easier to work on. For example, on my YM240 I can reach under the dash to replace the tach (or anything under there) in maybe 5 minutes tops.

I just found a photo I made illustrating this. Somebody had asked what belongs under there.
http://www.tractorbynet.com/forums/...47857-wiring-ym240-p1580202ym240underdash.jpg

The difference is significant to me right now because I'm in the middle of rebuilding the steering box on my more-complex YM186D. It's column shift goes through the dashboard and *everything* between the driver and the engine has to be taken apart to pull the fuel tank under the cowl, in order to get the steering box in. Grumble.

 

[284 International]

California, I hope you're taking pictures as you go along doing your steering box, for when mine does the same thing. My shifter is on the transmission tunnel, so that may be different.

 

[California]

You probably saw the thread I started on rebuilding the YM186D steering box. Mostly I was asking dumb questions - I'm not much of a resource for helping others yet.

On yours without column shift, the dash will come apart easier.

I'm still dinking around with the steering box on the bench as I find time, and haven't disassembled the dash (or pulled the fuel tank) which will be needed to install the box.

The Hoye text description, and their vids showing rebuilding the box, are the best resource after you get the box out.

The only tip I can add is what someone told me in my thread: to shrink a bearing shell so you can pull it, weld a bead around inside the ball track. I did that for the bottom of the steering column this afternoon after trying everything else. When I wiped the bead with a wet rag to cool it, the bearing rotated; the weld made it that loose relative to the still-warm housing it was in.

I'll update my thread when I can add something useful.