Mowing Mower check chains on B7500 - problems

[dannyk]

I have been using a 4 foot rotary cutter with my B7500 (no position control). To avoid the occasional lapse when I lower the three point hitch too far and the mower scalps, I decided to order the check chains (mower height adjustment chains from SSB tractor) that have been recommended on this forum. What could be simpler, right? /forums/images/graemlins/smile.gif

To my dismay, /forums/images/graemlins/frown.gif when I tried to attach the front slotted links of the assembly to my top link pin at the tractor, I found they would not fit.

The B7500 has only two holes in the bracket for the top link pin. There are two problems. First, the mounting bolts for the bracket with the holes interferes and does not allow the slotted links to be mounted. Second, even if I were to grind down the links to get them to fit, the links hit the PTO shield when the mower is lowered.

A mounting bracket with three holes (the third hole being higher and out of the way of the bracket mounting bolts) would solve the problem (I haven't checked to see if Kubota offers this as an option), although this would limit access to the hydraulic fill hole. Alternatively, I'm wondering if anyone has come across a better mounting point for the slotted links. (Perhaps the bolts which pass through the base of the fixed ROPS?) Has anyone used these bolts to mount the slotted links? Other ideas?

I would sure like to hear from other B series users who have used the height limiter chains on a B-series tractor. Thanks,

Dannyk

 

[dwhite]

I had the same problem with a neighbor's Woods finish mower. I took off the PTO shield to make room for the chains. Now I've bought a Befco mower and need to replace the shield.

 

[mcycle]

Dannyk, Under the seat of my B7500hst, there is an adjustment bolt where you can limit the drop of the 3point arms. I've did this adjustment and now I do not need check chains. My brush hog is set at 3 inches off the ground in the front. When I lower the 3pt. , that's where it stops. Hope this helps.

 

[djradz]

Were you not able to also take advantage of the other use of the check chains, that is providing a constantly level cut over varying terrain? Your brush hog top link had to toggle, but with that feature, your deck did, or at least could have "floated".

 

[dannyk]

mcycle, yeah, I wondered about that "implement height adjusting screw." Even tried to turn it, but it wouldn't budge, and I was afraid I'd break something trying to loosen it. I also wasn't sure it would actually hold the weight of the implement because it seems like such a puny mechanism. Apparently it works, according to your experience. I'll have to try some acetone to dissolve the paint at the base.

djradz, could you elaborate a bit more about what you mean "the other use of the check chains?"

Thanks guys,
dannyk

 

[mcycle]

Dannyk, Yes, that adjustment bolt was extremely tight on mine also, but after working with it for awhile, it came loose. It's sort of a pain to get it adjusted for the right height you want, but after it's set, it works like a charm. I only use the 3pt. for the rotary cutter, so I never have to change that adjustment bolt setting. Just the first time & it's done.

 

[RickNC]

Danny,

See my post under "Attachments." Maybe it will help.

Good Luck

 

[djradz]

Danny, I'm probably getting to sound like an old broken record to may here at TBN about this topic, but to me, check chains are one of the greatest add-on, and probably the most underused improvement that can be made to any rear mower or rotary cutter. Having or not having position control on the 3-pt makes no difference. What happens, as long as you have a deck that has a toggle or otherwise moveable top link at the point where the tractors adjustable (or for some, hydraulic cylinder) top link attaches is this:

With the use of check chains, the deck is allowed to "float". The 3-pt adjustment lever is set to allow the lower links to go to there lowest position, but because of the chains, they never get there. The chains stop the deck from falling completely. Now this may seem like it's just for those that have no position control, or for other situations where maybe the 3-pt hydraulics are old or leak, but that's not what I'm talking about. With the chains now supporting the front of the deck, and the rear wheel(s) of the cutter following the ground, the deck truly does just float along. No more of the deck bouncing up and down with every little bump that the front of the tractor incures. The deck now rides along with the large, and usually very stable, rear tractor tires. I've been so impressed with this setup over the years that even if I ever invest in a new mower deck, I might just remove the front wheels and revert back to the check chains to support the front. You might also want to search for more info under "check chains" in previous postings.

Remember, for the chains to really do the job, you need a deck that has the moveable top link. Most now do, for other reasons, but without one, the chains only do half of what they can.

 

[dannyk]

Well, I GUESS my mower top link is moveable. It doesn't have the swivel link that yours does, but the mower front A-frame is connected to the rear A-frame by a short length (4") of chain. In addition, the lock nuts connecting the front A-frame to the mower deck can be loosened slightly so that the front A-frame will pivot at it's base. I don't really know if they are designed to be loose, however.

I've been thinking of manufacturing a third and higher hole to attach the check chains to the tractor, since my bracket for the top link has only two holes. I could do this by making two steel pieces with thee holes in each piece. The pieces would stand vertical on either side of the top link mounting bracket and the two lowest holes would align with the two holes in the bracket. The lowest hole would be held by a bolt and nut to the tractor bracket. The middle hole would be held by the top link mounting pin with top link attached. The highest hole would hold the check chains on another pin, and the chains would then be free and clear of the PTO shield. Any comments on this brainstorm, anybody?

Regarding the implement lowering screw on the B7500, I found that it was easiest to remove the entire rod asssembly from the tractor to adjust the locknut and hex bolt since this can be done by removing a rear slip washer and a front pin. I then put the assembly in my vise to loosen the lock nut and shift the bolt and nut assembly backwards on the rod before retightening. I just couldn't get enough torque on those nuts in the confined space under the tractor seat. Perhaps someone else will find this method useful. It is relatively easy to reattach the rod assembly to the tractor. Just raise the rear lift arms and everything will slip back into place.

Dannyk

 

[dannyk]

djradz, I notice that your check chains are attached to the front of your mower deck rather that to the pins on the mower for the lower lift arms. Any advantage to this method? thanks,

dannyk

 

[djradz]

Both my brush hog and RFM are set up that way. On my brush hog there was a hole already there and on the RFM I mounted the two large eye-bolts. The kit I made up didn't have a bracket to go over the link pins and I didn't like the idea of them attached there anyway, but I think that's the way most of the prefabbed kits come. Shouldn't be a problem. I just liked the idea of getting the chain as low as possible for the most lift.

I've seen the chain setup you're describing for your top link connection and that should work just fine. I believe it's just another way of providing a flexible connection so the tractor doesn't break the mower when starting to go up a rise. Couldn't you replace your top pin at the tractor with a longer pin or bolt so the chain brackets can go on the same holes as the top link connection. That's what I did.

 

[dannyk]

Djradz,

Thanks again for your response. Longer pins will not work, because a 5" pin would be required for the slotted tabs to clear the mounting bolts. A 5" pin will not fit into the hole because there is only 4.5" between the bracket and the ROPS base. Such an arrangement would also put the slotted tabs in very close proximity to the upper lift arms.

At the moment, I'm not sure it is practical to use the check chains with a small tractor such as the B7500. Is there any reason the top link could not be mounted in the lower hole? Then the slotted tabs for the check chains could be mounted on a pin in the center of the top hole. (The tabs would still have to be modified to clear the PTO shield.)

Dannyk

 

[djradz]

No reason I can see. As long as there's not interference between the chains and the top link, I think you'll be OK. Make sure you still get good lift of the deck with the top link in the lower holes. In general, on a smaller tractor, it's probably better to have the link in the upper holes, but if it works OK, I can't see it matters much.