Heisler 9 Speed - Farmall M

[Lfdfireman]

Just curious to get some opinions on the Heisler. I have the chance to pick up a Farmall M that has the Heisler 9 speed in it. I am not familiar with either the M&W or Heisler, but have heard they are pretty nice to have. The M wouldn't be used for anything other than occasionally mowing and maybe pulling a hay wagon for parades and such. No big field work or hard work for it. Just wondering about benefits and how easy they are work on and if it has issues, can you still utilize the tractors normal gear range. Appreciate any thoughts and/or opinions on it.

 

[glennster]

one of my m s. has the m+w 9 speed. makes the tractor a lot more useful. it gives you 4 more higher gears between the standard 4th and road gear, never had any problems with it. one thing to keep in mind when the 9 speed is in high range, the pto speed is doubled so be careful.

 

[used red MN]

I have no personal experience with them but I can tell you a little about hoe they work. If you know how most manual transmissions are set up and how they move the power through it is pretty simple. So most manual transmissions prior to the prominence of overdrive transmissions have a gear on the input shaft to the transmission that the shaft connected to the clutch turns. This gear is always in mesh with a gear on the lower shaft of the transmission often called the counter shaft. So when you let you foot off the clutch the lower transmission shaft is alway turning. Now the back part of the upper transmission shaft is connected by gear mesh to turn the wheels. So being as the Farmall transmission is pretty simple when you move the shifter to select a gear you are sliding a gear on the top transmission shaft to engage into its mating gear on the counter shaft. Then when you let the clutch up the machine moves power driven through the input gear, to the counter shaft and back up to the main shaft by the gear you selected. In a Farmall and many other pre-overdrive transmissions the highest speed is direct through the transmission by some sort of teeth or splines that connect the input shaft and the main shaft together so they turn the same speed. Because of this 5th gear in your tractor has no interaction with the counter shaft. Now hopefully you understand that. What the Heisler and M&W 9 speed do is change the ratio between the input shaft and the counter shaft. So when you select the the optional higher speeds it provides it is shifting the gears added during its installation to speed up the counter shaft in relation to the engine speed. When you shift out of the optional gears the transmission returns to the stock ratio between the input ..engine.. speed and the counter shaft. Even though this is done through a set of gears that are part of the installation. This is because the stock ratio has to be shift to ..neutral.. so to speak so the optional faster gears can take over. So as mentioned earlier 5th gear or road gear does not rely on power moving through the counter shaft so the speed it moves the tractor remains the same.
One thing those setup do when they are engaged is speed up the PTO speed. Also they raise up the speed the LiftAll belly pump turns because it is also driven by the counter shaft as well. So maybe this helps, maybe it was just garble. I will attach a video someone took in a museum in the county where the M&W version was manufactured. All the silver gears are the ones that were changed during the installation.
Display video

 

[Olyj1947]

Made that mistake splitting wood! But I realized my screw up in short order!

 

[Olyj1947]

I have a Hiesler in my M. I had already gone thru my diffential and just wanted the kit but the guy said to take it all. And glad I did. An old M that has been used on the road will have wear, a lot of wear on the 4th gear. When shifting down from 5th, 11 mph to 5 mph is a long way to go. My 4th was toast and ended up changing a lot from the doner tractor.

 

[BarnyardEngineering]

I have been on this, and other forums for many many years, and I can not recall ever having heard of anyone ever having any operational trouble with one of these 9 speed transmissions.

They are nice on an M because 4th gear is 5MPH wide open downhill with a tailwind. Excruciatingly slow if you're trying to get somewhere that you can't run in road gear, or are raking hay or doing some other task where you really don't need the tractor to be screaming the whole time and using all that fuel.

 

[TractorDad3]

Far from garble! Very interesting to read, especially for an untrained garage jockey like me. Thank you for posting.

 

[D Slater]

Hisler 9 speed has a shift lever like in picture located on left side of transmission housing. Shift lever located on left near clutch pedal with rod sifts the lever. See no sign of those in pictures on your other post. M&W used one model that shifted on left but not there. M&W used a shifter out on right side of Transmission housing and a cable shift. Cable passed through a hole drilled in center housing. Don't see in picture. Can you take picture on area below belt pulley and to rear of it? Looks like something different there. Not common but a gear box the replaced the belt pulley gear box was made. It only give one gear speed between forth and fifth. Don't see one of those.