I have an issue I never thought would happen.

[BubbaJr]

I was mowing yesterday, got down in the ditch by my mailbox and tried going up out of the ditch, and it just spun the tires. Put it in 4WD, and it spun all 4 of them. I grabbed the 3PT lever to raise the mmm, heard a big clunk that shook the tractor. Finally I got out of the ditch and got out to check. Couldn't see anything wrong at that point.

So I took off down the road to mow about a 1/4 mile of berm along my woods, got to the rest of my property, went down the ditch perpendicular like I always do, and heard another loud bang. Shut it down and gave it a closer inspection and discovered that the lift arm for the mmm rides on top of the 3PT arm on the left side was bent enough so that the lift arm would slip off the 3PT arm so that raising the mmm would only raise the right side of the deck.

I took it off, thought about trying to heat it up and bend it back, then 2 issues popped up in my head. One, this thing is made out of 1/2' steel, and my little propane torch would never phase it. Two, if I did manage to get it hot enough to bend I would also lose the temper in the metal. So I got online and found out that it will cost me at least $164 + shipping to replace this arm.

But I can't figure out what could have happend that would have caused this failure, any ideas?

BTW this is a 1 year old B2650 cab model with a 72" mmm.

Joe

 

[SDT]

I was mowing yesterday, got down in the ditch by my mailbox and tried going up out of the ditch, and it just spun the tires. Put it in 4WD, and it spun all 4 of them. I grabbed the 3PT lever to raise the mmm, heard a big clunk that shook the tractor. Finally I got out of the ditch and got out to check. Couldn't see anything wrong at that point.

So I took off down the road to mow about a 1/4 mile of berm along my woods, got to the rest of my property, went down the ditch perpendicular like I always do, and heard another loud bang. Shut it down and gave it a closer inspection and discovered that the lift arm for the mmm rides on top of the 3PT arm on the left side was bent enough so that the lift arm would slip off the 3PT arm so that raising the mmm would only raise the right side of the deck.

I took it off, thought about trying to heat it up and bend it back, then 2 issues popped up in my head. One, this thing is made out of 1/2' steel, and my little propane torch would never phase it. Two, if I did manage to get it hot enough to bend I would also lose the temper in the metal. So I got online and found out that it will cost me at least $164 + shipping to replace this arm.

But I can't figure out what could have happend that would have caused this failure, any ideas?

BTW this is a 1 year old B2650 cab model with a 72" mmm.

Joe

More than likely, your MMM was caught on something when you tried to raise it, which is why you could not drive out. The 72" MMM is not a suspended deck, but rather, uses gage wheels (best MMM, BTW). If one is not paying attention, one can high center the tractor onto a single wheel, forcing the wheel into the ground. Attempting to continue forward can damage the wheel or deck. If one is attempting to force forward direction while lifting the deck, I can see how the lift mechanism could be damaged.

The 72" MMM is quite rugged and forgiving but there are always limits.

Any good welder/fabricator can straighten your bracket.

SDT

 

[diesel85]

Yes, find a welder in your area.

There are like 10 around in my neck of the woods, including me.

 

[sixdogs]

More than likely, your MMM was caught on something when you tried to raise it, which is why you could not drive out. The 72" MMM is not a suspended deck, but rather, uses gage wheels (best MMM, BTW). If one is not paying attention, one can high center the tractor onto a single wheel, forcing the wheel into the ground. Attempting to continue forward can damage the wheel or deck. If one is attempting to force forward direction while lifting the deck, I can see how the lift mechanism could be damaged.

The 72" MMM is quite rugged and forgiving but there are always limits.

Any good welder/fabricator can straighten your bracket.

SDT

That's probably what happened.

It could be straightened but if you want to buy new that would be OK as well. If something won't look just the way I think it should and I can afford it at the time, I buy new.

 

[BubbaJr]

I've been gone all day. When I got home I went out to look at the area where it happened and found some ruts in the dirt where the mmm wheels dug it up. The above scenerio sounds very plausible.

The strange thing is that i've been mowing that exact area the same way for over 16 years without any issues. Must have been the luck of the draw.

By taking it to a welder, do you mean using a blue nosed wrench to heat and beat it into submission? Won't that destroy the temper of the steel. I would think that quenching it afterward would make it brittle and more apt to snap it off rather that bend it.

Tomorrow morning I'm going to take the part to the dealer and see if it is still in warranty before I do anything else.

Thanks very much for the comments.

Joe

 

[sixdogs]

Let us know what they say.

 

[Dave M7040]

I've been gone all day. When I got home I went out to look at the area where it happened and found some ruts in the dirt where the mmm wheels dug it up. The above scenerio sounds very plausible.

The strange thing is that i've been mowing that exact area the same way for over 16 years without any issues. Must have been the luck of the draw.

By taking it to a welder, do you mean using a blue nosed wrench to heat and beat it into submission? Won't that destroy the temper of the steel. I would think that quenching it afterward would make it brittle and more apt to snap it off rather that bend it.

Tomorrow morning I'm going to take the part to the dealer and see if it is still in warranty before I do anything else.

Thanks very much for the comments.

Joe

If there is no warranty, which is what I expect, then take the $ you would pay a welder to straighten it and buy a low cost hydraulic press and straighten it yourself.
Having a press is a valuable addition to any shop.

Dave M7040

 

[rbargeron]

I.........do you mean using a blue nosed wrench to heat and beat it into submission? Won't that destroy the temper of the steel. I would think that quenching it afterward would make it brittle and more apt to snap it off rather that bend it........

The lift arms are likely not tempered - not high enough in carbon to even respond to heat treating. All the steel linkage parts I've ever worked on our K machines have been low carbon steel (dead soft) that can be tied in a knot, cold straightened and work just fine. Heating them red does make them easier to bend, but the residual effect is near zero. The blades on a rotary cutter are a different story. Dick B

 

[mcfarmall]

Low carbon steel can be heated and quenched to your hearts content and will do nothing to the grain structure...High carbon steel on the other hand is a very different story.

 

[BubbaJr]

Good news, I went to the dealer this morning and the part is under warranty. They are going to have to order it, but they say they will request rush shipping, and I should have it by tomorrow or Wednesday. The parts manager said he has never seen that happen before.

Now that I have some time, I'm going to go out to the barn and go over all related parts and make sure I didn't miss any other damage.