Losing belt on mott flail mower on bumps

[id_0]

I have two mower decks for my 1952 Cub, and both are giving me problems. The woods mower needs a new clutch assembly, but the mott flail mower is what is my trouble now. The blades seem to be very dull, and don't cut very well. However, I am not sure that new blades will improve the cut. I would appreciate any experience and suggestions on this. At this point I only use it to rough cut the acreage. However, the main issue is with the belt. The mounting assembly (belly) is custom in the rear for the belt to the PTO, but seems solid and well engineered. The rear bracing is to the rear hitch assembly. It is mounted to the hitch from below (would mounting it upside down change the angle of the mower to increase performance?). The front is mounted as designed, and only the lifting arm assembly is custom, but again seems appropriate for the task. It seems well mounted, and works on flat, smooth ground, where the roller does not come in contact with any roots or ruts, etc. The problem is that if I hit a root or go over rough ground the mower deck will take the impact, and bounce slightly (on the chains) but the rear hitch (the whole hitch to the tractor, not just the mower) comes loose after a short time, and pivots upwards creating slack and in the belt and it slips off the pulleys, leaving the PTO spinning on its own and the belt on the ground behind me. I have tightened the bolts as strong as I dare and it doesn't seem to help. Has anybody experienced this, and found a solution? I have tons of small roots lying just above the ground, and avoiding them is impossible. This is one of the reasons I use the flail mower in the first place, as I suspect the woods mower's clutch assembly wore out from hitting the roots too many times (The slip mechanism no longer has distinct steps, and are rounded so much they don't have enough bite to engage the blades.) I hope I have explained this well enough to understand. If necessary I can upload photos of the mower attached to the tractor, but I am hoping that is is a commoin enough problem that somebody has already solved it, and recognizes the description. I am hoping that there is a better solution than, just don't go over small bumps or roots.

[tst]

does the mower have the support brace that goes from the mower to the torque tube on the tractor?

[Eugene]

Up load your photos. Can't visualize how you have the idler pullies mounted.

When mowing rough ground, I set the roller into it's highest position (blades are lower to ground) then float the mower (suspended) so that the roller does not touch the ground.

You may need a new belt. Check the alignment of the left idler pulley and the mower deck pulley.

Edit: Lots of photos. There are a number of Mott flail mower owners on this site.

[Denny Clayton]

I have two mower decks for my 1952 Cub, and both are giving me problems. The woods mower needs a new clutch assembly, but the mott flail mower is what is my trouble now. The blades seem to be very dull, and don't cut very well. However, I am not sure that new blades will improve the cut. I would appreciate any experience and suggestions on this. At this point I only use it to rough cut the acreage. However, the main issue is with the belt. The mounting assembly (belly) is custom in the rear for the belt to the PTO, but seems solid and well engineered. The rear bracing is to the rear hitch assembly. It is mounted to the hitch from below (would mounting it upside down change the angle of the mower to increase performance?). The front is mounted as designed, and only the lifting arm assembly is custom, but again seems appropriate for the task. It seems well mounted, and works on flat, smooth ground, where the roller does not come in contact with any roots or ruts, etc. The problem is that if I hit a root or go over rough ground the mower deck will take the impact, and bounce slightly (on the chains) but the rear hitch (the whole hitch to the tractor, not just the mower) comes loose after a short time, and pivots upwards creating slack and in the belt and it slips off the pulleys, leaving the PTO spinning on its own and the belt on the ground behind me. I have tightened the bolts as strong as I dare and it doesn't seem to help. Has anybody experienced this, and found a solution? I have tons of small roots lying just above the ground, and avoiding them is impossible. This is one of the reasons I use the flail mower in the first place, as I suspect the woods mower's clutch assembly wore out from hitting the roots too many times (The slip mechanism no longer has distinct steps, and are rounded so much they don't have enough bite to engage the blades.) I hope I have explained this well enough to understand. If necessary I can upload photos of the mower attached to the tractor, but I am hoping that is is a commoin enough problem that somebody has already solved it, and recognizes the description. I am hoping that there is a better solution than, just don't go over small bumps or roots.

I think I'm reading you to say the drawbar loosens up on you and bounces up. Do the drawbar bolts look like the one in the below picture? If not, regular bolts will loosen up with vibration.


Image from DE Farmall Cubs

[id_0]

After looking online for phtots of the D9 and D95 Mott flail mowers I was able to determine what I think is the problem.

The custom made idler pulley assembly mounts on the Cub frame above the trailer hitch, instead of on the trailer hitch itself. The mowers tail assembly does mount to the trailer hitch (belly mower), but the pulleys are above it, and offer no force (good or bad) to the trailer assembly. So... My guess is that the original idler pully mount (H295 on the parts diagrams) allows tension from the belt to absorb the vibration and bumps. And if the mower deck bounces and shocks the trailer mount on the bolts, this tension provides downward force (as the belt would get tighter with upward movement of the trailer mount assembly) and would not cause the belt to loosen and slip off the pulleys.

Now... The major problem in fixing this is that I called around to places that sell Mott parts, such as flail-master, and the assembly has been discontinued. Therefore, I have to look for this part on For Sale sites, or have somebody fabricate that part again for me. The one I have now came with the flail mower, and is obviously fabricated, as the bolt hole are jagged and rough. It is solid and well designed, but I doubt they took into consideration this defect in design.

[id_0]

Just anotehr thought... Has anybody tried to mount the mower on the trailer hitch upside down, so that the force is downward, and not upward? That would change the pitch of the mwer deck slightly, and put the blades lower to the ground... MIght solve the issue with the belt and give me a better cut... Just a thought. Anybody try this and get good/bad results to share?

[Eugene]

Photos, would help in diagnosing the problem.

As I previously stated. My first problem with the Mott throwing belts was that I needed to move the mower deck about 3/4" to the left. This lined up the idler pulley with the Mott deck drive pulley. I had to move the mower deck even though the deck came off of another standard Cub

My second problem, when my Mott starts to the throw belt, replace the belt. The belt only seems to last 2 or maybe 3 years.

[id_0]

Here is a photo of the custom idler pully assembly I have for my Cub/Mott flail mower combination. Note it mounts on the left-side bolts above the trailer hitch assembly, not on the trailer hitch, as I see in most photos online.

I am almost positve that this was manufactured by a previous owner, as the bolt holes in the metal plate are rough and not perfectly round (as if they were pounded out, or torched out). This is not something I would expect from Mott. Perhaps it is for another model Cub (lo-boy?) or tractor, but I have not seen this design in any photo.

I am thinking that this placement is causing most of my belt slipping problems, as the mount on the trailer hitch assembly would give different forces against the belt and trailer hitch during bouncing of the Mott mower deck while going over roots, etc. Wouldn't the belt get tighter if the trailer hitch loosened and bounced upwards? The idelr pulley would drop, as the end of the trailer hitch went up. The belt would tighten, and stop the upward movement. Correct? In my design (see photo) the belt is not attached to the trailer hitch assembly at all, and is independent, therefore having no effect on the hitch movement.

[id_0]

Photo. Original was too big.

[Eugene]

Not a Mott idler pulley bracket. The Mott idler pulley mounts where the nut is welded to the draw bar and the bolt immediately to the right.

Thinking. Might be cheaper to buy a complete parts Mott flail mower than the idler bracket. Draw bar condition?

The adjusting lever is suppose to be flat. Might want to replace the pin in the adjusting lever with a bolt and tighten up the right arm.

[Scrivet]

To me, that picture of the idler looks like the original/early style pulley mounting. Possibly it has been flipped 180 front to back (don't remember for sure which way it mounted?????). The flat bar should continue across with an L shaped piece on the end of it bolted to the opposite final. Looks like it has been cut off and a brace welded in. Tried searching for a picture but can't find any, I know I've seen at least one on here before.

[John *.?-!.* cub owner]

The early mounts used a bar that was bolted to tabs welded to the drawbar brackets. The pulleys did look like the ones in the picture though. I do not remeber (not unusual for me) seeing that particular style mount before.

[Smokeycub]

Here's a pic of my Mott D9 mule drive.

untitled1.png (168.95 KiB) Viewed 746 times

It appears the angle of the dandle is wrong! lol Looks like Scrivet has it right, the mule drive looks to be cut off and installed back way around. Not sure if the angle of the idler on the right is ok or not, the angle looks too steep in the pic. Something looks odd with the tensioner too (besides the bent rod and the pin), that should all be tight and no play at all after the belt tension is set. The mower should have virtually no side to side play, otherwise the belt will get looser as you turn right. That combined with a misaligned idler would cause the belt to come off.

[John *.?-!.* cub owner]

I know it is a long ways from PA. but if you make it to Cubarama the end of this month (Fredericktown, Mo.) we will be doing a seminar on installing and maintaining the Mott flail mowers.

[id_0]

Results:

I have yet to find a standard idler pulley assembly, and suspect that this will be needed to completely remedy the situation. However, I took out the washers and used the bolts alone, and they sunk in deeper into the assembly and for now is keeping these from getting too loose to slip the belt easily. I have been a little reluctant to try it on the spots that seem to always toss the belt, but I think I can live with it this way for now.

On a second note, and to explain my reluctance to really test out the fix on rougher ground, I have replaced all the blades. I at first thought that the blades were old style and the new blades I saw on the internet from flailmaster were a slightly different design due to the changing times. However, the cut of the new blades is so good that I would easily say it gives a very manicured cut now. I therefore really think that the old blades were rough cut blades for brush. This is fine, as I have quite a bit of rough ground with brush that I was using this deck to clear, but now I prefer to use the new blades for the grassy areas. I have a gravely that I will now use on the rough areas, if I can get that to consistently run... So for those out there that have asked the question about how good the flail deck mows... The blades do really make a difference.

Still looking for the idler pulley assembly... but also maybe a second flail mower deck complete, so that I can have one for rough cut, and one for manicured lawns.