Rear draft arm linkage problem - 4110 MMM

[MikeFromVA]

I am about to go nuts. I lost my third turnbuckle on my rear draft arms yesterday. The MMM is held up by a pair of rear draft arms. They adjust by a turnbuckle in the very back. The turnbuck is attached to the draft arm assembly with a pin that has a hole in it. When I bought the unit, there was a circular retaining pin through the hole to keep the pin from slipping out. That pin is not cutting it...

I lost my first turnbuckle when boxblading without removing the whole draft arm assembly. My own fault - a mistake I won't make again.

The next week, I lost my second one (as well as the yoke it attaches to) while mowing. Giving myself the benefit of the doubt, I'm allowing for the fact that MAYBE I hooked something up wrong. I didn't double check, so I cannot be sure.

This week (a week after #2), I was VERY CAREFUL with assemby and double checking and checking every 25 or 20 minutes as I mowed. Well, after about 2 acres of mowing the pin had slipped out and I'd bent the heck out of a THIRD turnbuckle. Now these things cost almost $60 each. This has already cost me over $200. I can't afford to mow my lawn at this rate.

The guy at the parts counter recommended that I use a cotter pin rather than the retaining ring, but the hole on the pin is too small for a cotter pin of any significance. The picture in the MMM manual shows using those pins that are straight on one shaft and curved on the other to hold in the pin - they seem less sturdy than the retaining rings so I decided against that.

Anyone else have this problem? Anyone have a solution that they've tried?

 

[bigpete]

Hey there, Mike. I had a similar problem with my 4110 and 60" deck. Luckily it only happened one time and I was able to straighten everything out. When it happened, the left turnbuckle lost its pin on the front end (toward the deck), which drove the turnbuckle assembly into the ground. Fortunately, the soil was damp and I was going slow thorugh a corner when it happened. Just backed up and wrestled with the deck in the yard to get it attached again. I cussed quite a bit at it and lost a day of work around the house. I had to straighten a few things but nothing serious.

I am currently using the "hair pin" hitch pins like you described on the back end of the turnbuckles and split ring clips (the ones like key chain rings) on the front end of the turnbuckles. I will probably replace the rears with cotter pins when I get around to picking up a bag of them at the tractor store.

Here are a couple of links to define the pins I am talking about:
Hitch Pin or "Hair Pin" Clips

"Split Ring" pins

Split cotter pins

I guess I am wondering why this keeps happening to your rig. Since these cotter/hitch/split ring pins suffer no real stress except to keep the 5/8" (I think) pin in the yoke, what lateral stresses are your pins suffering that would shear them? If they are vibrating out, I would certainly go with the cotter or split ring pins. I keep the split rings in the front yoke attachment becuase this is the end from which I do my side-to-side deck adjusments. My second question is whether you have the deck height suspension turnbuckle option on your machine. If you do, you can hold your deck lift frame up while you do light boxblading. That way you won't have to remove the suspension frame every time you do ground engaging work. If you knew all that, disregard. /forums/images/graemlins/grin.gif

 

[MikeFromVA]

Pete,

Thanks for the response and the links. I don't know what the lateral stresses are. My field is a little bumpy so I get bounced around from time to time. I noticed the most recent damage just after going up and down a fairly steep hill a few times. I'm guessing that as I crest the hill, the mower is not floating but riding on the wheels if that has anything to do with it. I have ordered one of the kits to suspend the draft arms in the up position when I'm not mowing, but the last two have happened while mowing...

I will experiment with the pins in the links - some of them look like they might be promising...

 

[beenthere]

Put a cotter pin in that will just fit the hole. You won't have any more problem. Those circular ones are a pain in the ***

Are you busting through brush that causes the pins to bend?
Are you putting a washer between the pin and the linkage arm? That is important.

 

[bigpete]

Are you mowing with the deck "suspended," or is it running with the guide wheels on the ground all the time?

 

[bigpete]

<font color="blue"> Those circular ones are a pain in the ***
</font> Yeah, they are. But they are a necessary evil sometimes. lateral adjustments to the assembly are done from the front of the yokes on this tractors. As much as I take my deck off and back on, I need to adjust the frame pretty often. It beats pulling cotters with a needl nose and replacing them every time. The cotters are perfect for the back of the yokes, though.

 

[MikeFromVA]

beenthere-

I will find a small cotter pin and try it. It just seems like the ones that would fit there would be too darn thin to hold much of anything.

No, I'm not taking on brush at all - I have kept the field mowed for about a year now.

I have not tried a washer there, there is not one in the manual so I hadn't thought of it. It certainly cannot hurt to try it so I will.

Thanks for the tips!

 

[MikeFromVA]

Pete, I try to keep the deck suspended just above where the wheels contact on hard surface. On grass, the gauge wheels do spin as I'm mowing, but that is usually from the grass hitting them rather than the ground.

 

[bigpete]

Hi again, Mike. Do you have the deck suspension kit/latch kit installed? I run mine just like you describe. It seems the guide wheels turn in tall grass for me too. When I set my mower deck height with the latch kit, I then adjust my guide wheels on pavement to be about 1" above the pavement with the 3-point control fully lowered.

 

[millsnhills]

Mike,

I just wanted to reply and let you know you are not alone. I have replaced mine three times. I have just got to where I remove the whole shooting match if I am not mowing. Running rear implements and backing will kill ya.

I think it should be a requirement for deere if that sell a MMM on a tractor to include the lift kit or whatever it is called. When I purchase my setup it was with a rear implement, loader and all and until I found this site nobody had mentioned what would happen after removing the deck and trying to lower a box blade in reverse /forums/images/graemlins/shocked.gif Ouch a few times over