3-Point Hitch Kubota B3300SU + Zerco Check Chains + King Kutter Rotary Cutter

[jeff9366]

The Kubota B3300SU ( 33-hp / 1,800 pounds ) does not have POSITION CONTROL for the 3-Pt. hitch. Instead the B3300SU has 1/4"ing adjustment of the 3-Pt hitch, which is useful in its own way, but is NOT position control.

When using a rotary cutter ("Bush Hog") you wish the mower deck to return to the same height, exactly, after raising the mower or upsetting its position by bouncing over uneven ground. Height adjustment is critical on a rotary cutter where you want the revolving blade to cut in the arc near to the tractor and revolve freely as it passes through the arc at the rear of the tractor. For this reason you want the FRONT of the mower deck 1/2 to 1" LOWER than the mower deck at the REAR. When I mow that usually means 1-1/2" at the front, the grass cut height, and 2 or 2-1/2" at the rear.

On tractors without position control, such as the B3300SU, position control is accomplished with CHECK CHAINS. This post is an attempt to suggest check chains and make rigging mower-deck check chains simple.

Photo #1 + #2 Zerco Check Chains I purchased mine from Steven's Tractor in Louisanna; fairly close to Florida. Agri Supply in Virginia also sells Zercos. $30 + shipping.

Photo #3 Directions Zerco suggests two grab-link adjusting brackets should go on cross pin holding inboard end of top link. On the B3300SU there are two cross pins and not much room. Attached to one cross pin adjusting brackets are an awkward fit and the chains lie at too shallow an angle. I needed a higher grab-link bracket position.

Photo #4 View 48" KK Rotary Kutter in raised/transport position. Check chains slack.

Photo #5 Closeup of Check Chains Adjusting brackets mounted to pivot bolts for ROPS; required 1/2" longer replacement bolts. Brackets stay on the tractor.

Note lighter chain extension attached with one clevis on each side. This is to give finer height adjustment. Chain "Quick Links" would not be strong enough splice in this application.

(( Note aftermarket pin adjustable stabilizers by STABILWORKS have replaced Kubota turnbuckles. ))

Photo #6 Closeup of right Adjusting Bracket Extra chain dangling. Green cable tie marks link providing 1-1/2" cutting height.

Photo #7 Closeup of right Adjusting Bracket Extra chain secured.

Photo #8 + #9 Ready to mow/'hog - Ratchet Rake on the bucket.

Note: Kubota top link has been replaced by "Hydraulink" air over hydraulic top link. Hydraulink mechanism is excellent used with box blades. I am experimenting to see Hydraulink will be an improvement over King Kutter mechanical floating link. The Hydraulink provides shock absorption.

I hope this post assists others without position control for the 3-Pt. hitch.

LINKS:

Chain Limiter Kit

Kubota tractor stabilizers Kubota www.stabilworks.com - YouTube

[herringchoker]

Nice job and good write-up but it looks complicated to me. I'm cheap so I did this, it cost nothing (scrap steel) and it works great:

[jeff9366]

Works Great is key for both of us.

I wish I had the acquired welding skills before age 65 arrived.

My wife works cross-word puzzles. I write on T-B-N to exercise my writing skills.

[herringchoker]

Agreed. Glad it works for you. All the best.

[bikerdib]

Dang, I just had one of those DUH moments. I've been considering finding a way to make gauge wheels work on the front of my Bush Hog. Although I would still prefer the wheels since I mow some pretty uneven areas, the check chain idea is pretty neat. I have oxy/fuel torch and welder so I can make up my own check chains pretty easily/economically. I had just never seen it done before. Thanks guys!!

[jeff9366]

Although I would still prefer the wheels since I mow some pretty uneven areas, the check chain idea is pretty neat.

I actually bought two stiff springs, at $5.39 each, from local Ace Hardware with the idea of splicing one into each check chain, using a second clevis, for a little shock absorption.

Decided I should test current check chain rig thoroughly before complicating it. I returned the two springs. But I remember exactly where the Ace Hardware spring cabinet is.

[Baby Grand]

I think your ROPS is on borrowed time with that setup. The distance from where the chains connect to the ROPS to where the ROPS is bolted to the tractor is considerable, providing a long lever for a bouncing rotary cutter to start pounding on the bolted tractor/ROPS joint through that long lever arm. Personally, I'd try to cobble something together directly off the top link attachment point, or at least lower the check chain/ROPS attachment point to something like herringchoker shows. Not trying to be snarky and hope I'm not sounding that way, just wouldn't want to see you damage you ROPS - can't imagne what it would cost to replace. Then there's the whole safety thing, which I'll just avoid.

[jeff9366]

I 'hogged with two predecessor check chain arrangements from January 2012 to the present, without strain evident in the components or King Kutter. The predecessor was constructed from miscellaneous components sourced from TSC + Ace Hardware. Cost at least $30, equal to or more than the Zerco kit.

The Zerco arrangement is simpler. The Zerco chain is heavy gauge to support heavier rotary cutters than my 48" King Kutter. Were a chain to break, cutter would only fall max 5/8" (length of one chain link) before 3-Pt. lift arm supports it on that side. Note that I recommend clevis chain connecters and AGAINST threaded quick links. Not shown, but I use a strong bungee to tension each check chain away from PTO in unlikely event of check chain failure.

Zerco check chains were originally sold for the Ford 8N; they have proved over many years.

The new, longer ROPS pivot bolts are 5/8" Grade 8.

I can splice in a strong spring to each check chain as a shock absorber if I recognize the need.

Thank you for your view.

I respect your Randall Brown quotation.