For those who are looking for details on how to adjust the clutch on the old Master Mower Yazoo front mower 3 wheel units (the 60's and 70's old wheel in the back machines), here's what you adjust. See photo: Here is how I did it. Have fun and if you're doing this do it at your own risk!! The instruction Manual PDF found on the web says use two screwdrivers and pry against something (the shifter sleeve-see manual's diagram below) that'd be impossible to pry against without taking the transaxle apart. I didn't do that. I bent a 90 at the tip (heated red hot with a torch and bent it) of a small flat head screwdriver in order to get under the end of the lock spring clip. Once this is pulled out of it's current tooth on the adjusting wheel, the adjusting wheel teeth are a separate unit from the spring even though it looks like it's just a spring wrapped around a bunch of teeth. Go ahead and turn the adjusting wheel once the end of the locking spring clip is pulled out of it's current tooth. Before you do this, look at it a little bit and move the shifter and you'll figure out which way it needs to go to tighten or loosen the clutches. Take a picture of your original position just incase you need to go back to it if you mess up. The manual says this: Lastly, I took the belt off the input shaft pulley before I did this. It makes moving the clutches and gears much easier since you're not fighting against the engine anymore. Good luck. Supposedly you can loose the lock spring clip if you're not careful. I heard of one guy putting a rag behind it so if it did fall it would be trapped and not end up in the bottom of the transaxle case. This would be bad! Just be careful and take your time. Keep 30 weight oil in the trans and it should last well. The clutches are supposed to be half submersed in 10W30 non detergent motor oil.