3-bottom too large for JD 520?

[Coyotefred]

I'm looking to buy a 3-point moldboard plow to use with either my JD 60 (5300 lbs 37 HP) or JD 520 (4960 lbs 34HP). I don't have a manual for the 60 but I believe the 60 was rated as a 3 or 4-bottom plow tractor. The manual for my 520 has a 3-point (non-John Deere) implements page that lists both a 2 and 3-bottom moldboard plow and the appropriate load control yoke setting.

I'd prefer to use the 520 since it's in better shape and easier for me to use and maneuver. But I wanted to see if anyone thought I might have issues with a 3-bottom on this size tractor. 2-bottoms are more available but I'd like to be able to plow a wider area with each pass.

My soil is very fine sandy loam with no obstructions so that would be easier on the pulling than other soil types, but I would appreciate any opinions on this.

Thank you!

 

[Farmwithjunk]

The 60 would toy with 3 bottoms. The 520 SHOULD pull 3 in sandy soils, but would be at it's limit. Never saw a 50/520/530 pull 3 around here. Most used 2X14"'s.

 

[Coyotefred]

I know there are many variables involved, but what do you feel would be a more fuel economical choice in these times of high gas prices? I think the fuel consumption (* at "max load") on the 520 is 2.83 gal/hour compared to 3.32 for the 60.

Are you better off trying to run the widest (usually heaviest) plow you safely can at higher load/most gas consumptio since you're plowing more area per pass, or are you better off with a more modest plow that won't run the tractor at "max load" to maximize fuel economy even though you're plowing fewer inches per pass?

The 60 would toy with 3 bottoms. The 520 SHOULD pull 3 in sandy soils, but would be at it's limit. Never saw a 50/520/530 pull 3 around here. Most used 2X14"'s.

 

[milkman636]

How many acres? With smaller acreage a 2x16 would be a nice option that shouldn't tax your tractors too much. Fuel consumption will be lower than published max if your draft load is less on either tractor. As your torque reqirement drops off it takes less fuel (throttle) to maintain engine and ground speed.

If your regular plowing is a multi-day project, than you might want to take a shot at a 3 bottom and see how it does. There are some brands of plows that will convert from 3 bottom to 2 just by unbolting and reconfiguring some of the frame work. My Ford plow is like that.

 

[Coyotefred]

Which model Ford do you have that converts like that? That would be handy!

I'm trying to convert some heavily weed-infested areas to a mix of pasture grasses, and I plan on only plowing 3-5 acres per season so I can have manageable amount of seeding and following-up (weed control).

How many acres? With smaller acreage a 2x16 would be a nice option that shouldn't tax your tractors too much. Fuel consumption will be lower than published max if your draft load is less on either tractor. As your torque reqirement drops off it takes less fuel (throttle) to maintain engine and ground speed.

If your regular plowing is a multi-day project, than you might want to take a shot at a 3 bottom and see how it does. There are some brands of plows that will convert from 3 bottom to 2 just by unbolting and reconfiguring some of the frame work. My Ford plow is like that.

 

[Farmwithjunk]

A number of factors come into play. Way back in the 1950's and on into the 1960's, John Deere (among others) did studies that proved pulling a slightly smaller implement at a higher ground speed netted fuel savings. This is what led Deere to make the change to 4 and 6-cylinder engines with a wider operating RPM range, as well as adding more gears in the "field speed" range. In order to make the most of that potential savings, you had to have a tractor that is capable of operating at a wide range of speeds. For all their assets, 2-cylinder Deere's weren't exceptionally gifted at varying speeds.....VERY limited engine RPM range, and limited gear selection....

The theory of the day for Deere back in the glory days of the 2-cylinders was pile on ballast on an already heavy tractor and pull as big of an implement as possible at a relatively low speed. SOME consideration was taken as to fuel economy, but that was ALSO relative to what was common with-in the industry at that time. As fuel economy came front and center, Deere had already realized a change had to be made. (4 and 6-cylinder tractors had already started being developed in the early '50's)

Bottom line is, you won't notice a LOT of fuel savings one way or the other on such a small amount of plowing.....You aren't looking at more than 3 or 4 hours plowing AT THE MOST if using no more than a 2-bottom plow.

The only advantage I'd be considering is, making life easier on a 60+ year old tractor. What little time you MIGHT save by using the biggest plow possible is all but wiped out by the wear and tear you're placing on the old horses.

If it were me, I'd stay well below "maximum load" and go with which ever tractor is in the best shape overall, and a smaller plow than what is the most it can lug.

 

[Uncle Wayne]

The old timers in my area have told me the way to figure plow size for a tractor is to allow 1 hp per inch of plow pulled. If the plow has 3 sixteen inch pans then 3 x 16 = 48 hp required.

That ratio worked well for me with a CUT 4320 (48 hp) and plowing through red clay.

 

[grnspot110]

I used a 2-14" JD #810 plow on my 58-520. I bought it as a 3-bottom, but after using it, took it back to two. Three was just to big of a load in this area! 2-16" would have been better, but 14" is what I could find & parts interchanged with the #F45- 4-14" I had for my 720D. The 810 is made to unbolt the back frame & add or remove bottoms. ~~ grnspot

 

[Farmwithjunk]

The old timers in my area have told me the way to figure plow size for a tractor is to allow 1 hp per inch of plow pulled. If the plow has 3 sixteen inch pans then 3 x 16 = 48 hp required.

That ratio worked well for me with a CUT 4320 (48 hp) and plowing through red clay.

That'll "ball park it", but doesn't account for plow depth, ground speed, nor soil conditions in a given area. Around here, it'll soak up ALL a 60hp tractor has to offer pulling 3X16"'s @ 8" deep/5mph (+ or -) And I'm talking rated PTO hp at that, not engine hp.

 

[dreamer]

Coyotefred,

When I was a kid we had a JD 620 that I did alot of plowing with a two bottom plow. I don't know if it was 14" or 16". It would pull it great usually in 4th gear. I'm thinking a 3 bottom plow might be too much for your 520? Good luck.

dreamer.