Flail Mower Mott Flail mower repair advice

PRCWI · May 23, 2013

leonz said:
AH so it was the way you held the camera that distorted the photo.

I think its how the pic uploaded, when I look at it on my computer or when I click on the uploaded photo it rotates it to the correct orientation.

hawkeye08 · May 23, 2013

Take it to 4shorts in the north. He can fix it up better than new!

I would expect you could put the plate on the inside as you mention. You may not be able to have the end knives (loose one knife on each end). The way that looks, I am thinking you have a balance problem perhaps...

PRCWI · May 23, 2013

hawkeye08 said:
Take it to 4shorts in the north. He can fix it up better than new!

I would expect you could put the plate on the inside as you mention. You may not be able to have the end knives (loose one knife on each end). The way that looks, I am thinking you have a balance problem perhaps...

Haha, Its only about a 48 hour drive I'll get right on that.....LOL

On the knives I had another idea, I am going down this morning to measure, I think I can have the reenforcement plate cut circular just a bit smaller than the arc of the knives so that I don't have to worry about the knives hitting the added metal during operation. I think it will work but I need to measure to see how far out from the hole that will allow me to go.

PRCWI · May 23, 2013

Ok so on the subject of the blades hitting the sides here is how the math works out to keep the re-enforcement plate from hitting the side. The diameter of the blades circle is 15.75". The center hole for the bearing housing is 4.25" (actually slightly smaller) and the housing itself is 6" in diameter.

So my intention is to have a "donut" plate made that will have the center hole and will have a daimeter of 15" or 14.75". This will allow the "donut" to be welded in place to provide re-enforcement (5.25" of metal all the way around the hole) and still not interfere with the operation of the mower. I think it will work wonderfully and I intend to put a plate on both sides. That should ensure the other side doesn't suffer breaking issues as well.

Does that sound like it would work well?

Arc weld · May 23, 2013

All the Mott's I've ever seen, the side plates are welded on. A good welding/machine shop should be able to cut out the damaged section and weld a new piece in. Just make sure they take good measurements for the holes. They could most likely make a round plate which would make it a lot easier. Just welding new pieces in, I'd be worried about metal fatigue in the adjacent steel. I suspect the bad bearing(s) caused the problem.

PRCWI · May 23, 2013

They did take good measurements of the holes and I gave them the new and undamaged bearing housing to work from as well. so they have an exact example of whats going in and where the holes need to be.

As far as the break, there were no bad bearings, both bearings still spin well and freely. I think someone hit something hard or big with it before I bought it...or my better half did while mowing

Either way I, the bearing housing cracked where the grease zerk and line go in (basically its weakest point). I honestly think it had a hairline crack when I first got it because the first thing I did was look for all the grease zerks and grease it up, the manual said there should be a zerk and there wasn't so I found the hole were there had been a zerk, put a new one in and greased it up, but after running it when I went to grease it up again later the zerk was gone...I thought I hadn't screwed it in tight so I put in another one, but it wouldn't seat right and that was when I saw the small crack in the housing. I actually greased and used it a few more times last fall before parking it and the bearing was still full of grease and spinning fine this spring, but I didn't want to push my luck or cause worse damage.

Anyway, we'll see how good of a job the fabrication shop does and then how good the welder does on Sunday. Hopefully by Sunday afternoon or Monday we'll be laying down grass again in style.

2458n · May 23, 2013

I left my flail outside covered up. Someone of course had to see what was hidden underneath. Water and freezing weather are not your bearings friend. I feel you will be pleased with the results of your repair.

PRCWI · Jun 3, 2013

Well as it turns out the Mott changed the bearing style for the mower so I ended up having to order some spacers that you have to use with the new bearings. I also may have to fiddle with the belt drive pulley's to be sure they all are aligned after the change. We'll see. I wasn't able to get it fully put back together after getting the plates and having them welded in so now I have to wait till Friday to get it finished. Hopefully I'll be able to get it all put back together this Friday and be up and running for the rest of the season. I'll post some pics of the fix after it's all completed.