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Discussion Starter #1
I have a craftsman gt6000 (2012) model and I had a question about what is suppose to be the norm.

What should happen when I release the gas going just about any speed? On my model when I release the gas the tractor halts. The engine is still running and everything but its like the wheels lock up. Im and not sure what the purpose of the break is in this case. I have never really used the break because if I let off the gas it slows down. If I let off completely it halts ( almost enough to whiplash ) so much that my wife is afraid to even use it.

So is the break really just for emergencies or is this thing suppose to coast like a car when I let off the gas? if so what could be the problem.

I bought this less then a year ago at sears outlet with only 5 hours on it. I have only put 20 on it.

Thanks,
Joel
 

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Sounds about right both of my hydros work that way....maybe not to the point of whip lash :) but I hardly ever use the brakes unless I stop on a hill....then it will roll ahead on its own slowly.
 

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that is the way hydro's work, they do not free wheel, i use the brake as a parking brake also if you lock the brake on you can get off with the motor still running.
 

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:MTF_wel2:

Here's a graphic demonstration of the basics of how a hydro works. Note the direction of rotation of the motor on the right compared to the position of the control lever on the left and what happens when the control is centered in the neutral position. Neutral is effectively a hydraulic lock. The oil can't flow through the motor when the pump swash plate is in the neutral position unless the bypass valve is actuated to move the tractor by hand.


The parking brake is for parking. The hydro is much more effective for braking from travel because the operator can control the amount of braking force used, once he/she becomes accustomed to it.
 

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Discussion Starter #5
Wow, thanks for all the replies. This is reassuring to hear; I ran the problem by a couple of the guys at sears and they said it was a defect and that the tractor should coast when releasing the gas. I was a little uneasy but have come to learn that most sales employees really dont know that much about what they sell.

So if I am driving at 8Mph and I just slip off the petal at full speed, should the rear tiers lock and stop the tractor almost instantly? This is pretty much the case at slower speeds and I have always been afraid to try it.
 

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When the pedal goes to neutral, the rear wheels stop turning. How quickly the tractor stops depends on how smooth the ice is. On gravel, it will leave 2 very short skid marks.

Keep your foot on the pedal and adjust your speed as you do in the car. More pressure on your toes equals more speed, less pressure equals less speed, except there is no coasting. Consider it as a direct connection to the rear wheels. The pressure that you apply with your toe or heel is directly proportional to the speed, in both forward and reverse.
 

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I don't have a GT hydro (my GT is manual) but both the DYT 4000 and the PYT 9000 will roll away if I don't set the brake - well no problem on level, but even a gradual downhill requires I set the parking barke - hum, that may be when the engine is off, but if I want to get off while the engine is running (say to move something out of the way) I have to shut the deck down and set the parking brake to keep the engine running.

I'd have to check to see what happens when I take my foot off of the "gas" but keep sitting on the seat. I clearly have never had the sense the tractor is coming to a brake on stop when I lift off the forward, say when I want to go into reverse.
 

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Maybe you should try reading the manual about how to properly operate it. If you don't have a manual you might be able to get one at managemylife.com.
 

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Other than cutting grass, which I think the GT6000 does quite well, I am not a big fan of our 2011 GT6000. Hence, this is a favorable response for a tractor I don’t think too much of.


In the photo below, this cart has 14 cubic feet of volume. With the pyramid of dirt, that’s about another 4.5 cubic feet of space. With the moisture content of the dirt, I’d guess that it’s roughly 90 lbs per cubic foot, so there’s 1,670 lbs of dirt in the cart, and the cart's roughly 175 lbs. I normally haul everything with the 1989 GT18 that’s in the photo, but the seat pan broke yesterday, so I’ve been begrudgingly using the GT6000. Today, I noticed how well it would brake loads, so I made a few runs on the driveway's 12° driveway slope, which is a lot steeper than it sounds. I made a few passes starting off very slowly and gradually increased speed. Eventually, I ran down it at full throttle until it reached maximum speed, and the load started pushing me faster, then I left off the go faster pedal, and the tractor came to an abrupt, but completely controllable stop. I wouldn’t even begin to try that with the GT18 and it’s manual because as soon as I push in the clutch, the tractor picks up a dangerous amount of speed fast, and the break won’t hold it back.




I can’t believe how well it brakes loads that would be impossible with the manual transmission. With the GT18, I always have to stop atop large hills, select low range, and use the engine to brake me as I gingerly decend grades with heavy loads. The GT6000 dumps the cart better too because I can shake the tractor a lot more with the hydrostatic than I can with the manual in the GT18.

The tires don’t lock up, what they do is go to near zero rotation, but still spin rather slowly. With my foot off the forward/backward pedal, the load will push it down the hill, but it crawls. This only seems to happen whilst the engine is running, and the foot brake is released. When the tractor’s turned off, I have to set the parking brake on a grade or the tractor will roll away rather quickly.
 

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Now you know the benefits associated with hydro use. Total control of the power going to the rear wheels.

On a side note, it takes very little power to pull a cart with a ton of dirt. My Husqvarna YT with a K46 can, and has, done that on several occassions on level ground. Bringing that load to a halt from full speed on a steep slope requires traction as well as power, and the lightweight YT with its 3 hp hydro will be in serious trouble.

Rule of thumb: If you can accelerate a load from a dead stop up a grade with a hydro, you can also stop the load when going down the same grade with that hydro.

I wouldn't push that issue with a K46. Fortunately, my neighbourhood doesn't have much by way of slopes.
 

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Wow, a ton in that garden cart?? Looks like my 20 year old Craftsman cart which I have loaded with hardwood splits/rounds, and driveway gravel/stones about 1/2 full, but I'd never consider putting operating with a ton load...when pulling with my GT6000, a MT (bullet proof tranny), a 1993 version, pretty close the GT18 I think - they look alike.

Seeing your old GT18 encourages me to replace a leaky gas tank (storm damaged) and keeping it going. It has terrible brakes, I don't recall the last time I tried to adjust but I think it didn't help.

Needless to say I don't pull any heavy loads with my DT 4000 (also storm damaged) or my PYT9000.
 

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Wow, a ton in that garden cart?? Looks like my 20 year old Craftsman cart which I have loaded with hardwood splits/rounds, and driveway gravel/stones about 1/2 full, but I'd never consider putting operating with a ton load...when pulling with my GT6000, a MT (bullet proof tranny), a 1993 version, pretty close the GT18 I think - they look alike.

Seeing your old GT18 encourages me to replace a leaky gas tank (storm damaged) and keeping it going. It has terrible brakes, I don't recall the last time I tried to adjust but I think it didn't help.

Needless to say I don't pull any heavy loads with my DT 4000 (also storm damaged) or my PYT9000.
My cart is 17 cu-ft, and heaped like bolillo_loco's, that comes out to a tick over 2000 lb of dirt for a payload.

Gravel weighs 120 lb per cu-ft and hardwood between 40 & 60 lb per cu-ft, depending on species and moisture content.

For hauling heavy loads, a hydro is superior since it also performs the braking function. One of my hydros has not had brakes for over 20 years. I simply ground the FEL for a parking brake. With 54" of cutting edge in the ground, that tractor is going nowhere unless the engine is running and an operator is in the seat.

A visitor next door saw me hooking up a trailer with my MF12H and said "That little tractor can't pull that big trailer!" After hooking up to the ball, I slapped the drive control full ahead, and then did the same with the throttle from idle. The engine stumbled from the sudden demand for power and then settled in for max acceleration to top speed, about 8 mph. That took less than 15'.

The trailer was an 18' travel trailer and weighed 3600 lb. Absolutely no problem stopping it. That "little" tractor weighed over 1300 lb with its FEL, about the same as a similarly equipped Suburban. You can't do that with a manual transmission in a GT.
 

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Discussion Starter #13
Well im starting to feel better about purchasing my hydro now. I use my gt for cutting an acre of grass (aggressive terrain), mulching leaves, towing hardwood, plowing (moldboard), and cultivating (disc harrow). Turn tight is pretty amazing for grass but it is a problem when doing heavy ground work and not having a manual makes me wonder how I should be towing and plowing.

Everything I find online for plowing and stuff says put it in second gear. The combo of the throttle and the gear give you a stable platform for the job. So, my question has been how to I plow/tow with a hydro? Im assuming full throttle but do I lightly press the petal and go slow or mash it and go fast? If I was in a car I would want slow speed high rpm so I could get more power but how do I accomplish this in a hydro? When Im towing 1500 lbs how do I get the same effect?

Thoughts?
 

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The only ground engagement work I've done (box grader/grader) is with my 6 speed manual and I always went as fast as I could while maintaining traction and getting the results I want.

Yes, operate at full throttle, that the maximum torque range (power range). Full throttle may also result in best cooling of the hydro - there is a cooling fan on the hydor, right? I believe it is spinning at engine rpm, not ground speed.
 

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Well im starting to feel better about purchasing my hydro now.

So, my question has been how to I plow/tow with a hydro? Im assuming full throttle but do I lightly press the petal and go slow or mash it and go fast? If I was in a car I would want slow speed high rpm so I could get more power but how do I accomplish this in a hydro? When Im towing 1500 lbs how do I get the same effect?

Thoughts?
That is dependant on the task at hand and the quality of the hydro. The hydros found in older GTs and in the heavy GTs can withstand a lot more abuse than the ones in LTs and light GTs.

A hydro has 2 speed controls, the swash plate which is controlled by the drive control pedal or lever, and the throttle which controls the the input rpm. It has one power control, the throttle.

Basically, adjust the throttle for the power required to do the job and the drive control for the speed range that is needed.

For precision movement of the tractor, a lower throttle setting is desired. This limits the top speed and the power that can be applied, but both can be applied in infinite increments within that lower range.

When high power at low speed is required, a high throttle setting and limited movement of the drive control will get the job done. For high speed, high power requirements, WOT and full drive control movement.

The options are endless. Refer back to my post on moving the travel trailer. The rig started to move with the throttle at idle and full forward on the drive control. It could have also started at WOT and slight movement of the drive control and that would have required much lower internal pressure in the hydro. I was showing off the capabilities of the tractor, but was also within the capabilities. The current crop of entry level hydros will not tolerate that type of power demand for long.

For short duration low power tasks where some precision is required, such as moving a trailer within the yard, hydro cooling is not critical. For long duration high power tasks, such as ploughing a field, hydro cooling is critical and high throttle settings are required to get maximum air flow over the hydro.

A hydro can deliver maximum torque to the final drive at any throttle setting and any position of the drive control. A gear drive can only deliver maximum torque to the final drive at maximum throttle in the lowest gear.

To get movement, you need both torque and horsepower.

Play with it. You will learn.
 

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Discussion Starter #16
That is dependant on the task at hand and the quality of the hydro. The hydros found in older GTs and in the heavy GTs can withstand a lot more abuse than the ones in LTs and light GTs.

A hydro has 2 speed controls, the swash plate which is controlled by the drive control pedal or lever, and the throttle which controls the the input rpm. It has one power control, the throttle.

Basically, adjust the throttle for the power required to do the job and the drive control for the speed range that is needed.

For precision movement of the tractor, a lower throttle setting is desired. This limits the top speed and the power that can be applied, but both can be applied in infinite increments within that lower range.

When high power at low speed is required, a high throttle setting and limited movement of the drive control will get the job done. For high speed, high power requirements, WOT and full drive control movement.

The options are endless. Refer back to my post on moving the travel trailer. The rig started to move with the throttle at idle and full forward on the drive control. It could have also started at WOT and slight movement of the drive control and that would have required much lower internal pressure in the hydro. I was showing off the capabilities of the tractor, but was also within the capabilities. The current crop of entry level hydros will not tolerate that type of power demand for long.

For short duration low power tasks where some precision is required, such as moving a trailer within the yard, hydro cooling is not critical. For long duration high power tasks, such as ploughing a field, hydro cooling is critical and high throttle settings are required to get maximum air flow over the hydro.

A hydro can deliver maximum torque to the final drive at any throttle setting and any position of the drive control. A gear drive can only deliver maximum torque to the final drive at maximum throttle in the lowest gear.

To get movement, you need both torque and horsepower.

Play with it. You will learn.

So If I wanted to pull a trailer or attachment or anything really and only wanted to go 2Mph (is this what you meant by precision?) I could pick lowest throttle with gas fully depressed, or med throttle with gas 1/2 depressed, or full throttle gas partially depressed? All these combinations would be full torque? My take from what you said is the biggest difference would be cooling.

I have a 2012 GT600. It is a heavy beast and has a 26 horse Kohler vTwin courage pro engine. It has blasted its way through anything I have put in its way except for plowing through 1in diameter roots, railroad ties, and concrete slabs. None of these were intentional. I discovered them after I ripped them up.
When I hit these the tractor was sitting there at full throttle, gas fully depress and the wheels were not moving at all. I was concerned that I could ruin the tranny at that point.

Do you think my tranny is cut out for the heavy work?

Thanks.
 

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Sounds TOO heavy to me. I'd never let a tractor sit for longer than it takes me to remove my foot from the peddle if the tractor hit something at full throttle, peddle and wheels stopped rotating.
 

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I have tractors with hydros at both ends of the spectrum and each gets used according to its capabilities. The light tractor is used at high throttle settings because it has limited power transmission capability, about 3 hp at the rear wheels. The heavy GT mostly at about 2/3 throttle due to its higher power transmission capabilities, about 11 hp to the rear wheels.

The actual horsepower delivered to the rear tires is directly dependant on 2 factors, the throttle position and the drive control position. Max power is only available at max throttle and max speed. If either control is reduced, so is available power. My 2400 lb, 16 hp GT typically breaks traction in dirt (compacted or otherwise) at about 5-7 rear wheel horsepower. Higher throttle settings are reserved for higher desired tractor speeds or tractor powered implements. The lighter YT with its less capable hydro needs a higher throttle setting just to deliver adequate power to the ground for the limited work that it can do.

Your Craftsman GT is somewhere in the lower end of that spectrum, above the K46 that is in my Husqvarna YTH 20B42T, and well below the Sundstrand Series 15 that is in my MF1655. You will note the horsepower discrepancy between the engines in those 2 tractors, the light YT with 20 hp and the heavy GT with16 hp. One is designed to deliver hp to its implements (and bragging rights), and the other to deliver power to the ground as well as implements.

Understanding the complicated relationship between engine rpm, drive control (gas pedal or fender mounted lever), and traction capabilities takes time and use to assimilate. For most, WOT and drive control adjustments for the task at hand. Once the relationship is understood, reduced throttle settings can be used to fine tune power to the rear wheels and travel speed.

Precision manoeuvering would be something like clearing the snow away from the side of your new Cadillac with a FEL and dragging a wider back blade behind the tractor at the same time. High speed does not enter the calculations. You want enough power to push and pull the snow while still having time to make steering corrections. Speed in this instance can be measure in very few inches per second. High power settings and a sneeze can result in several thousand dollars in damage... and one really ticked off wife.

Torque is the misunderstood child of tractor power. It is what is required to get a tractor moving so that horsepower can keep it moving. It determines the rate of acceleration, but it requires no motion to be measured. It is measured in a hydro at the maximum pressure that can be obtained for doing work. It is not there at idle or at full throttle if the tractor is doing no work.

Take the time to read this thread from another forum. I spent many hours writing my posts dealing with torque in this thread starting at Post #17.


When I hit these the tractor was sitting there at full throttle, gas fully depress and the wheels were not moving at all. I was concerned that I could ruin the tranny at that point.
Maximum load at maximum throttle with no wheelspin equals heat generation in significant quantity. That is also the maximum torque available... and it's not enough!


Is your hydro designed for heavy work? That depends on your definition of heavy, how much time is involved at that level, and how well it is maintained. Will it exceed the capabilities of a K46? ... Probably. Will it equal a Sundstrand? ... Nope. For that you require a top of the line tractor from JD or some other major player.

Hydros generate heat. The heat generated is consistant with the amount of work done and the time involved in the doing. Pulling trailers is not heavy work. A small group of children can do that. Pushing concrete slabs is heavy work. If the wheels don't spin and the slab doesn't move, it's too heavy for your hydro.
 
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