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John Deere TiresWhen choosing the right tractor for your needs you will also be faced with making a proper tire selection. And when you are a first time tractor buyer it is difficult to know what is best. I know I struggled with this decision when buying my tractors. The tires are classified in the industry as R1, R3, and R4 which designates the construction, sizes, and treads.
The R1 tire is the “agricultural” tread which is the most aggressive in providing excellent traction and is superior in the field and muddy conditions. There are 2 different types of R1 tires, rice paddy found on the Japanese tractors and regular Ag tread found on most farm tractors. Rice paddy tires have deeper lug treads which help “paddle” the unit through very wet muddy conditions. Regular Ag is more of the field tire if choice. It does not have as deep of a lug as the Rice paddy tire and yet it still provides excellent traction. The R1 Ag tire provides a better ride on the fields and roads. R1 tires are also self-cleaning so when operating in muddy conditions the distance between the lugs is large enough that the mud has a difficult time sticking to the tire. R1 tires also are the narrowest of the three.
R3 tires are generally known as “turf” tires and are most commonly found on the golf course or the typical riding mower. Turf tires are grass friendly and tend not to tear the ground up, especially in soft wet conditions. They also have the most ground contact area since they have the shallowest tread depth. R3s do provide the smoothest ride compared with the other two types. R3 tires are also the widest of the three to help provide a large ground contact patch to yield a large traction area to the ground. This tread pattern is not very efficient in a muddy environment. Bear in mind though, one can still do damage to the lawn if the wheel is allowed to spin.
The last is the R4 or “industrial” tire. This tire is commonly used by contractors, landscapers, and now home owners as an all-purpose tractor tire. It has large, shallow, closely spaced lugs that provide traction and is still easy on the lawn. The R4 tread is designed similar to the R1 in that it tends to be self-cleaning. The R4 tire has a very sturdy sidewall construction capable of handling heavier loading. This means that if you have loader work, these tires will handle it unlike the R1 and R3 with softer sidewalls. R4 tires provide great traction and being that they are wider than the R1 tire, they gain the advantage of extra contact with the ground. Due to its large contact area with the ground the R4 tire is easy on the lawn. In 2wd, the R4 tire will be no more damaging to a lawn than a R3.

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Jul
10

Mower Deck Maintenance

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John Deere mower deckOver the past several years lawnmower manufacturers have been changing the design of the lawnmower deck and how it functions. Originally the decks were designed to rest on the ground with its gauge wheels supporting it. This allows the ground to completely control the contour and height of the cut directly related to the deck. The new designs now suspend the deck from the tractor with the gauge wheels set at about a quarter inch above the ground when the blades are set to the proper cutting height. The difference here is the tractor wheels now control the contour and height of cut. The gauge wheels only prevent scalping of uneven ground. I myself really prefer the new designs as I feel a much better finished result is achieved.
Now let us focus in on the deck maintenance. The majority of the deck maintenance is the same regardless of the mounting design. For example, cleaning, lubrication, blade sharpening, bearing and belt inspection and replacement are all the same as before. And basically, so is gauge wheel inspection and maintenance. The gauge wheels should need replacing less often without the deck being supported by them less often.
OK, now on to the major difference of these two designs. I was wondering if anyone else heeds the advice of their operator’s manual for their mower deck. I currently own a 62C and 72 John Deere mower decks. The 62C is mounted on a 2305 John Deere tractor and the 72 is mounted on a 2520 John Deere tractor. Both of my owner’s manuals have detailed procedures for leveling the mower deck front to back and side to side. I just did a recheck on mine and they were both in need of adjustment. The 62C needed the front to back tweaked and the 72 needed the side to side. I cannot recommend more highly the use of the leveling gauge sold by John Deere. What a great inexpensive tool. It really makes the job go so much more smoothly. Incidentally, I did check the level of both decks as delivered straight from the dealer when new and found that they did require some slight adjusting at that time as well. I am thinking that a level check is only needed every couple of years, or unless there is sufficient reason to do so sooner.
I find that doing my maintenance in the fall after the mowing season is finished works the best for me. I clean, inspect, and fix all that needs attention. I also sharpen and balance the blades at this time. Then come spring, all I have to do is mount the decks and mow. I do however check my level at this point rather than the fall. Having well maintained and leveled mower decks really yields premium results in a well groomed lawn.

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Jul
09

PTO Shaft Geometry

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John Deere PTO ShaftPTO vibration is caused by the universal joints and is especially pronounced when cornering. The output velocity of a single U-joint operating at an angle fluctuates, even though the input velocity is constant. This output velocity fluctuation becomes greater as the angle of the U-joint is increased. To eliminate the velocity fluctuation and hence the PTO vibration, two universal joints are used. The velocity fluctuation caused by the first U-joint is cancelled by the second U-joint, only if both are operated at the same angle and are in phase with each other.

Since most tractor/implement PTO‘s use the two U-joint system, why may there still be PTO vibration? It is because the U-joints are not operating at the same angle. Most tractors with a 540 rpm PTO have a distance of 14 inches from the end of the tractor PTO shaft to the hitch point. Most implements, however, have a distance greater than 14 inches from the hitch point to the end of the implement input shaft. This design is necessary to allow sufficient telescoping action of the PTO shaft, so the shaft does not bottom out on sharp turns and does not allow the two parts of the PTO shaft to separate when the PTO is in line with the drawbar. This geometry however, does not allow the U-joints to operate at equal angles, when cornering.

Many implement manufacturers are supplying a tractor hitch extension with their implements. This extension increases the distance from the end of the tractor PTO shaft to the hitch point. The implement and PTO shaft are designed around this new geometry so the U-joints will operate at equal angles. This geometry is commonly called the EQUAL ANGLE HITCH. Existing equipment can be modified to obtain an equal angle hitch. For example, a 540 rpm PTO driven machine is hitched to a tractor. The distance from the end of the tractor PTO shaft to the hitch point is the standard 14 inches. The distance from the hitch point to the input shaft of the machine is measured and found to be 20 inches, making the overall distance 34 inches (14 and 20). For the PTO to operate at equal angles the hitch point should be 17 inches (34 divided by 2) from both the end of the tractor PTO and the input shaft of the machine.
A 3 inch extension is bolted to the tractor drawbar and the machine hitch is shortened 3 inches. It should be noted the overall distance of 34 inches has not changed and the original PTO shaft can still be used. However, the machine cannot be operated unless the drawbar extension is bolted to the tractor drawbar.

As mentioned earlier it is important to phase the U-joints correctly. Proper phasing of the U-joints allows the velocity fluctuation caused by the first U-joint to be cancelled by the second. Improper phasing compounds the velocity fluctuations and will cause severe vibration. The two parts of many PTO shafts are designed to fit together the correct way only.

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Changing Oil in Your John DeereThere seems to be more and more first time owners of sub-compact and compact tractor owners. I too joined this ever growing group back in 2008 when I first purchased my 2520 John Deere with a 72 inch mower deck and 60 inch brush. And then, not to long after the front end loader, a must have if you own one of these machines. A lot of learning now faced me as I started to use my machine. You know, 4wd, differential lock, power steering, 3 point hitch, and not to mention all the cool hydraulics. It does seem like a daunting task but, just take one step at a time, master it, and then move on to the next. And before you know it you’ll know what every lever and foot pedal does.

If you again are like me, then you will be doing your own maintenance on your pride and joy. There is no better way to really know your tractor than to do your own maintenance. And as I already stated, there are some completely new systems on these machines. For example, all new to me is the hydraulics, not so much the hydrostatic drive, but the increased complexity and all the auxiliary options. Then there is the added fact these machines are diesel, which again, is all new to me, and lest we forget, a cooling system and 4wd to learn and take care of. This is just the maintenance to deal with just the tractor alone. Along with it come all the attachments that require their own understanding and maintenance. But, that is completely another topic.

Once you thoroughly learn all about your tractor you are ready to test your knowledge and put it to use. Suddenly you are finding tasks using your new powerful machine to do things you never dreamed of before. And the ones you did know of have become so easy and pleasant they are not enough to feed your desire to spend more time in its seat. Moving mulch, mowing the lawn, grading the lane, and re-contouring the landscape is actually become tasks that you are looking forward to doing. And now suddenly you have noticed that the hour meter is hitting that precious 50 hour mark. Why is the 50 hour mark so important? It is where John Deere recommends that the oils and filters be changed.

As big a company as John Deere is I must give them credit in that they really do a pretty good job with their owner’s manuals. Now mind you, the still make a few mistakes here and there, but on the overall they are pretty good. I know that from tractor to tractor some of the maintenance intervals very. But, my point being that the owner manual won’t let you down. So just follow it step for step and you will make for some happy tractor time. And if that still isn’t good enough, just come and join us at GreenTractorTalk.com.

John Deere Mower BladeThere is more to a mower blade than most people realize. At first glance they seem overly simple, yet there is a lot going on here with that single blade of steel. I will not get into the engineering details of material selection, hardness, or other specifications here. But, what I will cover is some important basic details that one should know about in order to properly care for their blades. I am not going cover all the blade types, high lift, mulching, and such. If properly maintained you will have a smooth running and cutting blade. The blades and the deck need to act as one to lift the grass, cut it, and then discharge it.

Let’s first discuss a brand new blade and its cutting edge and length. Have you ever noticed when looking at a new blade the cutting edge is what would appear to most of us not sharp? This cutting edge and angle is actually at the perfect configuration for a clean and smooth cutting blade. Contrary to what most of us think, the cutting edge does not need to be razor sharp. In fact, a slight 1/32 blunt face will cut just fine and actually maintain its sharpness longer. The angle of the cutting edge is also important. If it is too steep the blade will not cut the grass, but tear it instead. If it is too shallow, it will dull quickly and not push the grass around to the deck discharge chute efficiently. This is why it is important to maintain the cutting angle when you sharpen your blades. Also, blades are measured diagonally from cutting tip through the mounting hole center to opposite cutting tip.

Now, let’s talk blade sharpening. The first thing I do after removal is to thoroughly clean the blade of all old dirt, grass, and grime. I then inspect the blade for wear and straightness. If bent, I straighten it if I can. If not, it is time for a new blade. I then clamp the blade in a vice and use a 4 inch angle grinder with a flap wheel. I have found this to be the easiest and fastest way to sharpen blades. As mentioned earlier, you must maintain the cutting angle and it does not need to be a razor sharp edge. Once both cutting edges are sharpened you need to check balance. This can be done with a very inexpensive balancer or something as simple as a nail in a vice. You of course will need to remove material from the heavier side to get good balance. If you ignore balancing, you’ll find you will have a very rough running deck. Not to mention you may experience prematurely replacing spindle bearings. Make note that each time you sharpen your blade you are also making it shorter.

One other thing you should be aware of when inspecting the blade. Make sure that the turned up wing behind the cutting edge is in good condition. If the undercut is excessive, you’ll have a very dangerous situation where the wing could become a flying projectile.

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