Removing Blades from Rotary Cutter

[trook]

I need to change the blades on my JD MX6 rotary cutter, and the nut in question is 1.5". For those of you who have already done this, can the 1.5" nut be removed with a normal 3/4 drive socket and ratchet, or will a 1/2 drive air impact wrench do the job? Please don't tell me I will need a 3/4 drive air impact wrench.............

 

[BlacknTan]

Most nuts on rotary cutters are in the 450 ft/lb range.

Check the torque capabilities of your impact gun, make sure you have enough air pressure and go to it.

About a 5' cheater bar should also do the trick.

 

[Avondale]

I have a Bush Hog (5 ft) with twin blades. It has 1 & 11/16th" nuts. Pretty hard to find a socket but found a 3/4" drive one and a reducer to 1/2" drive for my impact. Worked ok after soaking everything with pen oil. Big problem was bashing bolt out. You need to support the blade while whacking the bolt (leave the nut on at the end of thread) to release the keyed shank from the boss. Good luck.

 

[jdtractor]

hi i would just use the cheater bar method,works for me everytime! impact would be nice but i dont have one at my convience, right now its at another job site.just my .02cts

 

[dex3361]

I have used my HF earthquake impact to remove the bolts on my King Kutter several times with no issues.:thumbsup:

 

[deere5105]

Just took the blades off my MX6 to sharpen this past weekend. Used 3/4" drive set with pull bar and about 3' cheater pipe. Had to put some pressure on it, but came right off.

 

[twoone]

Well now you know how to remove the bolt. Putting it back on is another story you will need a way to hold the other end(help) while you torque the bolt. to 450lbs as the blade swings free. Paul

 

[deere5105]

I was suprised that while using a breaker/pull bar and extension through the access hole in the deck that I didn't experience a lot of movement. Once I got the pull bar and cheater bar together and the extension against the access hole nothing else moved. The square head of the bolt kept it from turning when the nut is being turned and the bind through the access hole kept the stump jumper from turning. I put it back the same way I took mine off. I can't guarantee it is a specific amount of ft lbs. but it is equal to the pressure it took to get it off.

 

[gwdixon]

Well now you know how to remove the bolt. Putting it back on is another story you will need a way to hold the other end(help) while you torque the bolt. to 450lbs as the blade swings free. Paul

Hey twoone! Esparto - I'm just south of you in Allendale.

Anyway, a good 1/2" drive impact wrench will work just fine with a 3/4" adapter. Check the specs on it to make sure it will handle the torque requirements. The high torque models don't come cheaply. Mine was just under $300 some years ago.

Been taking off those nuts for 30 years with no problem. I do coat them once with anti-seize, which will get the safety police screaming, but never have had one come loose.

The weight of the blade will usually pinch the bolt enough to hold it in place while the nut is screwed in from the top through the access hole. Not sure exactly how a MX6 looks underneath but that method works on Bush Hog and Landpride.

 

[psj12]

I use a 3/4" impact. The problem with using a large impact on a small compressor setup is not the lack of pressure but the lack of flow or volume caused by the small hose and tank fittings. I temporarily screw a 1/2" ID hose directly into the drain hole on the bottom of my tank and then I have several second of full 3/4" power before I have to stop and let my compressor cath up. This is ususlly plenty to break the nuts loose.