Bush Hog BH25 yokes breaking

[Boatman62]

I take care of some equipment for my neighbor, fixing broken things and maintenance. He has a BH25 that has broken the yoke bars a number of times and I was trying to figure out why and it seems a manufacturing defect. Where they stamp the bend at the factory it seems its somewhat shearing the steel. 3 of them have broken this summer. This last one only made a couple laps around the field. So I investigated the break a little closer and can see there isn't much metal left to break.

Anyone else had/have this issue?

The pics of the broken ends are two different yoke arms.

 

[Gee Ray]

There seams to be a to be two fold problem. First I would weld some reinforcement on the arms, then paint them up and run them. Second I would remove the top link. I would guess the field is very rough or the mower is being forced against a solid object. Perhaps the field has a ditch and as the rear tractor tires drop into the ditch the bar becomes overloaded because the movement allowed by the top link is not enough.

Use a piece of chain to replace the top link so the mower can still be lifted.

 

[ptsg]

Ditch the flat bars, replace those with chains and be done with it. And doing this way, the top link can stay connected as it will still be able to float just fine.

Something like this:

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[LD1]

I hope they are being replaced under warranty.

Is the flexible A-frame and toplink working as it should and have plenty of travel? Or is it bottoming out on uneven terrain and causing extra stress on those links.

If being covered under warranty I guess I'd keep trying the OEM ones until the issue goes away. If you are having to buy the parts....Go to a steel supply place and have them make you some out of hot rolled bar. Those look like they are cold rolled and by nature is a little more brittle and breaks alot easier if it gets bent.

 

[Boatman62]

I hope they are being replaced under warranty.

Is the flexible A-frame and toplink working as it should and have plenty of travel? Or is it bottoming out on uneven terrain and causing extra stress on those links.

If being covered under warranty I guess I'd keep trying the OEM ones until the issue goes away. If you are having to buy the parts....Go to a steel supply place and have them make you some out of hot rolled bar. Those look like they are cold rolled and by nature is a little more brittle and breaks alot easier if it gets bent.

No warranty..... both the dealer and BH have said its user error. That top pic is the latest failure. You can see it's partially broken before even being used.

 

[Boatman62]

It's quite possible that there isn't enough free play. He has about 200 acres he cuts twice a year. Part of it was an old apple orchard that the pulled the trees.

My question was more geared to if anyone else has the yokes break and noticed they seem to be compromised right from the start.

I think the best solution is to go with chains. I can reinforce and weld the bars but if hes breaking the bars from bottoming then something else will have give at some point.

 

[LD1]

Was that pic of the one partly broke happen on the same day it was installed.

Or was this a second mowing with it on...and it was partially compromised already?

If that stress crack happened....and he waited only a few days or a week them went back at it and it broke.....good chance it wasn't shipped like that, rather it was compromised by something he did the first time he mowed

 

[Boatman62]

Was that pic of the one partly broke happen on the same day it was installed.

Or was this a second mowing with it on...and it was partially compromised already?

If that stress crack happened....and he waited only a few days or a week them went back at it and it broke.....good chance it wasn't shipped like that, rather it was compromised by something he did the first time he mowed

Same day.

 

[Boatman62]

Also point out hes not new to mowing. Been doing for 20+ years. Breaking the yokes is new. First one was replaced maybe 2 years ago. Since then it's been an ongoing issue.

 

[wirlybird]

Can we get more pictures of the setup? How the top link attaches?
In my opinion I'd say 1 breaks it is a manufacturing issue.
3 break in one season and it is more likely to be a set up or use issue. Unless the 3 came from the same batch, manufacturer, etc.

I's take them to an experienced welding/machine shop and see what they say the cause of the break is.
To snap a bar like that is highly unusual.

Also, were those bars replaced and where did they come from? Was the first break an original one?
Looking at a picture of the BH25 the bar looks to be angled where it bolts at the rear and not straight like his appear to be.