Flail Mower Mott Flail mower repair advice

[PRCWI]

Hi guys,

New poster but have been lurking here for a while and appreciate all the great help and advice that's given. I'm in need of some now.

I have a Mott/Alamo SD88 mower and the bearing housing on the drive side cracked. I didn't think much of it other than that I needed to replace the part. I ordered the new bearing and housing from Flailmaster and today was going to swap the old for the new and be back in business.

However when I was taking off the old bearing/housing I discovered the frame behind it is cracked/broken in several places. In fact 4 of the 6 mounting holes are broken. :thumbdown:

So now I am trying to figure out the best way to fix it. The only thin I can think is have a plate made and placed behind the existing frame with the proper hole cut out for the shaft and then after welding it in place then weld the broken bolt holes back in place on the frame and new piece. Then drill new bolt holes through the new piece and mount everything back up.

Does that sound like the right plan? I'm not a welder so I am going to have to get someone else to do all this for me and I want to make sure with all the force that's going to be there that we're doing it the best possible way the first time.

Any advice is appreciated. I will try to get some pictures up so you all can better see what I'm dealing with.

 

[aczlan]

Sounds like a plan that could work. I would take it into whoever is going to weld it and ask their opinion.

Aaron Z

 

[leonz]

Hi guys,

New poster but have been lurking here for a while and appreciate all the great help and advice that's given. I'm in need of some now.

I have a Mott/Alamo SD88 mower and the bearing housing on the drive side cracked. I didn't think much of it other than that I needed to replace the part. I ordered the new bearing and housing from Flailmaster and today was going to swap the old for the new and be back in business.

However when I was taking off the old bearing/housing I discovered the frame behind it is cracked/broken in several places. In fact 4 of the 6 mounting holes are broken. :thumbdown:

So now I am trying to figure out the best way to fix it. The only thin I can think is have a plate made and placed behind the existing frame with the proper hole cut out for the shaft and then after welding it in place then weld the broken bolt holes back in place on the frame and new piece. Then drill new bolt holes through the new piece and mount everything back up.

Does that sound like the right plan? I'm not a welder so I am going to have to get someone else to do all this for me and I want to make sure with all the force that's going to be there that we're doing it the best possible way the first time.

Any advice is appreciated. I will try to get some pictures up so you all can better see what I'm dealing with.

View attachment 318759View attachment 318760View attachment 318761

LUCKY YOU,

You will be able to unbolt the side weldment/side frame of your mower and take it to a machine shop and have them fabricate a new one which wil be much faster to do. I also think you should take the left side off and replace that one as well as the bearing as they are both bad or nearly so.

Stress cracks/breakage like this is not limited to one side of a flail mower.


Having both side plates replaced will cost you much less money than a replacement mower of that size.

IF it is an actual ALAMO CHOKE, GAG, BARF, you should be able to purchase the replacement side weldments from one of the regional ALAMO sales reps.


Thankfully Mr. Mott thought long and hard about building these beauties and the european builders will learn much from an old mott mower too.
_______________________________________________________________________
Once you go flail you never go back!
Pronovost or not at all!!!

 

[PRCWI]

I don't think the side plates just unbolt....I think they are welded on...but I'll look. If they did I would think they would be a part you could order or find online.

 

[PRCWI]

Yeah I just went and checked, the sides are welded on, not bolted. Maybe this is an older model and the newer ones bolt on?

Anyway if I was going to have a whole new side manufactured it would include cutting off the existing side and welding on a new one.

 

[BukitCase]

Your idea, "have a plate made and placed behind the existing frame" - I'm not familiar with your particular flail, but I would think that might change the distance between end plates enough to screw up the spacing where your flail's rotor sits - in that whatever thickness the added plate, the space for the rotor would be shortened by that amount.

Like I said, I don't have that model (have a 73" Caroni) but you may want to check into that before you get too far along... Steve

 

[PRCWI]

Your idea, "have a plate made and placed behind the existing frame" - I'm not familiar with your particular flail, but I would think that might change the distance between end plates enough to screw up the spacing where your flail's rotor sits - in that whatever thickness the added plate, the space for the rotor would be shortened by that amount.

Like I said, I don't have that model (have a 73" Caroni) but you may want to check into that before you get too far along... Steve

Yeah I was looking at that. I could put the plate on the outside but if I do that the bearing housing will be that much farther out and that is the side that the drive pulley mounts to. There is enough clearance on the inside though I may want to keep the plate small enough to keep it inside the rotating blade path as that will also make that clearance smaller if its outside of that.

 

[leonz]

Hi guys,

New poster but have been lurking here for a while and appreciate all the great help and advice that's given. I'm in need of some now.

I have a Mott/Alamo SD88 mower and the bearing housing on the drive side cracked. I didn't think much of it other than that I needed to replace the part. I ordered the new bearing and housing from Flailmaster and today was going to swap the old for the new and be back in business.

However when I was taking off the old bearing/housing I discovered the frame behind it is cracked/broken in several places. In fact 4 of the 6 mounting holes are broken. :thumbdown:

So now I am trying to figure out the best way to fix it. The only thin I can think is have a plate made and placed behind the existing frame with the proper hole cut out for the shaft and then after welding it in place then weld the broken bolt holes back in place on the frame and new piece. Then drill new bolt holes through the new piece and mount everything back up.

Does that sound like the right plan? I'm not a welder so I am going to have to get someone else to do all this for me and I want to make sure with all the force that's going to be there that we're doing it the best possible way the first time.

Any advice is appreciated. I will try to get some pictures up so you all can better see what I'm dealing with.

View attachment 318759View attachment 318760View attachment 318761

Sounds like a plan that could work. I would take it into whoever is going to weld it and ask their opinion.

Aaron Z

LUCKY YOU,

You will be able to unbolt the side weldment/side frame of your mower and take it to a machine shop and have them fabricate a new one which wil be much faster to do. I also think you should take the left side off and replace that one as well as the bearing as they are both bad or nearly so.

Stress cracks/breakage like this is not limited to one side of a flail mower.


Having both side plates replaced will cost you much less money than a replacement mower of that size.

IF it is an actual ALAMO CHOKE, GAG, BARF, you should be able to purchase the replacement side weldments from one of the regional ALAMO sales reps.


Thankfully Mr. Mott thought long and hard about building these beauties and the european builders will learn much from an old mott mower too.
_______________________________________________________________________
Once you go flail you never go back!
Pronovost or not at all!!!

I don't think the side plates just unbolt....I think they are welded on...but I'll look. If they did I would think they would be a part you could order or find online.

Yeah I just went and checked, the sides are welded on, not bolted. Maybe this is an older model and the newer ones bolt on?

Anyway if I was going to have a whole new side manufactured it would include cutting off the existing side and welding on a new one.

Are you sure you see weld bead there? I do not. I see at least two bolts and nuts in your
image at the 9 amd ten oclock positions that would tell me that that the side piece unbolts
and can be replaced.

The other issue is the steel plate that would be placed in the interior of the shroud;
The outside side slicers will most likely impact it at some or all points and render the knives
useless.


About adding a pice of steel to the outside to repair it will be problematic as the
rotor shaft stub is only so long in length.

Your idea, "have a plate made and placed behind the existing frame" - I'm not familiar with your particular flail, but I would think that might change the distance between end plates enough to screw up the spacing where your flail's rotor sits - in that whatever thickness the added plate, the space for the rotor would be shortened by that amount.

Like I said, I don't have that model (have a 73" Caroni) but you may want to check into that before you get too far along... Steve

Yeah I was looking at that. I could put the plate on the outside but if I do that the bearing housing will be that much farther out and that is the side that the drive pulley mounts to. There is enough clearance on the inside though I may want to keep the plate small enough to keep it inside the rotating blade path as that will also make that clearance smaller if its outside of that.

 

[PRCWI]

Are you sure you see weld bead there? I do not. I see at least two bolts and nuts in your
image at the 9 amd ten oclock positions that would tell me that that the side piece unbolts
and can be replaced.

The other issue is the steel plate that would be placed in the interior of the shroud;
The outside side slicers will most likely impact it at some or all points and render the knives
useless.


About adding a pice of steel to the outside to repair it will be problematic as the
rotor shaft stub is only so long in length.

Those bolts are for bolting on the skid plate for the mower, that is actually the bottom of the side and would normally be resting on the ground. The side is fastened on with one continuous weld all the way around. It is NOT a bolt on piece.

You may be correct on the outermost knife. I won't know until we get it fully fixed, but I don't see another option other than fully removing the entire side (By cutting it off and having another one manufactured. Worst case scenario I could always still do that so I am willing to take the chance on the inner plate.

Hopefully there will be just enough clearance there to be able to allow the knives to be useful.

 

[leonz]

Those bolts are for bolting on the skid plate for the mower, that is actually the bottom of the side and would normally be resting on the ground. The side is fastened on with one continuous weld all the way around. It is NOT a bolt on piece.

You may be correct on the outermost knife. I won't know until we get it fully fixed, but I don't see another option other than fully removing the entire side (By cutting it off and having another one manufactured. Worst case scenario I could always still do that so I am willing to take the chance on the inner plate.

Hopefully there will be just enough clearance there to be able to allow the knives to be useful.

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

 

[PRCWI]

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]

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]

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]

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]

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]

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]

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]

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.