pwright
Gold Member
It's normal for mine. :laughing:
It definitely doesn't like going up steep (20%) hills in high and not so keen on medium either. I usually change to low for them.
Attacking that power problem CT225
- Thread starter bbse
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It's normal for mine. :laughing:
It definitely doesn't like going up steep (20%) hills in high and not so keen on medium either. I usually change to low for them.
arnoldziffel
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When negotiating hills, do you press the HST pedal all of the way forward or just part way?
MtnViewRanch
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No, if anything you let up on the pedal. I believe that that is why many HST owners-users do not like HST transmissions, they don't quite get how that they need to be used, and end up getting frustrated.
arnoldziffel
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MtnViewRanch,
Could you please explain how letting up on the pedal improves hill climbing ability?
Could you please explain how letting up on the pedal improves hill climbing ability?
SSdoxie
Elite Member
As you push down on pedal to increase speed is equal to shifting into a higher gear in gear transmission machine. Letting off the pedal to slower speed is equal to 'down shifting" to a lower speed that will increase torque through the drive system and require less horsepower to get same job done.
arnoldziffel
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SSdoxie,
Does the increase in torque happen in all three ranges?
Does the increase in torque happen in all three ranges?
MtnViewRanch
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If you mean by letting up on the pedal do you have more power in each range, then yes that is how it works.
SSdoxie
Elite Member
The HST pedal controls volume of oil flowing out of the pump to the HST motor which then turns the gear box & differentials (determines speed). The pressure required to move depends on the load, resistance to move. Flow @ pressure determines the horse power required from the engine. When trying to do a specific job and engine starts to labor, reducing the flow (let up pedal) reduces the HP requirement to engine.
Quick example: I don't know what full pump flow capacity is but I'll use 15 GPM as example.
At full pedal 15 GPM, if load resistance requires 3000 PSI = 26 HP from engine to move. If you let up on the pedal to flow @ 13 GPM at 3000 PSI load= engine only needs to put out 22 HP to move the tractor.
Quick example: I don't know what full pump flow capacity is but I'll use 15 GPM as example.
At full pedal 15 GPM, if load resistance requires 3000 PSI = 26 HP from engine to move. If you let up on the pedal to flow @ 13 GPM at 3000 PSI load= engine only needs to put out 22 HP to move the tractor.
arnoldziffel
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My brain is wired poorly for topics like this.
I'm sitting here really trying to grasp this concept.
Don't I need MORE power to get up the hill? If I had a 40hp or 50hp tractor would I still need to let-up on the pedal?
I'm sitting here really trying to grasp this concept.
Don't I need MORE power to get up the hill? If I had a 40hp or 50hp tractor would I still need to let-up on the pedal?
art
Super Member
At a certain point of weight to horsepower you do overcome it. But other wise to down shift a hydro you let up on the petal.