Run at Full Throttle?

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Tried_it

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I bought a new Cub Cadet XT2 Enduro Series GX54D lawn tractor with the 25-hp Kohler engine.

According to the owner's manual, the engine should be run at the fast setting of the throttle, a/k/a full throttle, wide open.

It goes against the grain with me to run an engine wide open if I don't need that much power for the job at hand.

Why is it recommended to run at full throttle? I know the engine is air cooled, and there is a fan atop the transaxle. Is full throttle recommended for engine and/or transaxle cooling?

I'm not much of a small engine mechanic. I'm using this thing to mow and to pull a 50-inch wide, wheel-powered sweeper to pick up pine straw.

It was expensive, and I want to take good care of it. If full throttle is the way to go, then so be it. I just don't understand why?
I didn't need the manual to figure out my Scag 61" Turf Tiger w/same engine had to be run at full throttle. Otherwise it failed to keep all 3 blades spinning fast enough to cut, plus hydraulic pump required RPM, and it cooled better.
 

tadawson

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Don't know much about engines, do ya.





But of course, you know way more than these guys......
I know I am a licensed pilot, and can read both Continental (Lycoming is the same) and Cessna's docs, and with both, you are told to generally avoid full RPM/throttle other than takeoff . . . and I trust them a lot more than these derps . . . (who I also note are from the eperimemtal world, where some things are viewed differently . . . I'm talking amout commercially produced aircraft, whether it be jet, turboprop, or piston . . . and even if the claims are true for the engine alone, youmdom't fly just the engine, you fly the entire aircraft where,
again, due to air resistance, etc. you dom't get best fuel economy at higher speed . . . the physics says so.

Then there is the minor little detail that purported "efficiency" is largely irrelevant in power equipment, since you can't seriously be saying that a machine that can do a job at say, 2400 RPM and part throttle will burn more fuel than running wide open, at who knows what speed? (The typical 3600 still isn't wide open, it's governed . . .true "wide open" would likely overrev and blow it . . .) So, it's really comes down to part throttle vs. part throttle, and I find it comical at best to claim the superiority of one over the other . . .

I stand by my statement (and published docs) that non adjustable throttles are in the same category as limiter caps . . . EPA mandates that have *ZERO* to do with use cases! And, why do folks always seem to duck the point that EFI engines, with thier far more accurate metering and ability to meet emissions over a far wider range of settings, don't seem to have this restriction, rather tending to have full throttle control. If the argument thr full speeders are making is true, induction system type should benirrelevant, hut it appears to not be the case either . . .
 
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heyinway

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I bought a new Cub Cadet XT2 Enduro Series GX54D lawn tractor with the 25-hp Kohler engine.

According to the owner's manual, the engine should be run at the fast setting of the throttle, a/k/a full throttle, wide open.

It goes against the grain with me to run an engine wide open if I don't need that much power for the job at hand.

Why is it recommended to run at full throttle? I know the engine is air cooled, and there is a fan atop the transaxle. Is full throttle recommended for engine and/or transaxle cooling?

I'm not much of a small engine mechanic. I'm using this thing to mow and to pull a 50-inch wide, wheel-powered sweeper to pick up pine straw.

It was expensive, and I want to take good care of it. If full throttle is the way to go, then so be it. I just don't understand why?
Do as the operator manual says. Period, end of conversation.
 

RevB

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I know I am a licensed pilot, and can read both Continental (Lycoming is the same) and Cessna's docs, and with both, you are told to generally avoid full RPM/throttle other than takeoff . . . and I trust them a lot more than these derps . . . (who I also note are from the eperimemtal world, where some things are viewed differently . . . I'm talking amout commercially produced aircraft, whether it be jet, turboprop, or piston . . . and even if the claims are true for the engine alone, youmdom't fly just the engine, you fly the entire aircraft where,
again, due to air resistance, etc. you dom't get best fuel economy at higher speed . . . the physics says so.

Then there is the minor little detail that purported "efficiency" is largely irrelevant in power equipment, since you can't seriously be saying that a machine that can do a job at say, 2400 RPM and part throttle will burn more fuel than running wide open, at who knows what speed? (The typical 3600 still isn't wide open, it's governed . . .true "wide open" would likely overrev and blow it . . .) So, it's really comes down to part throttle vs. part throttle, and I find it comical at best to claim the superiority of one over the other . . .

I stand by my statement (and published docs) that non adjustable throttles are in the same category as limiter caps . . . EPA mandates that have *ZERO* to do with use cases! And, why do folks always seem to duck the point that EFI engines, with thier far more accurate metering and ability to meet emissions over a far wider range of settings, don't seem to have this restriction, rather tending to have full throttle control. If the argument thr full speeders are making is true, induction system type should benirrelevant, hut it appears to not be the case either . . .
So...you must be that guy that just stays below 3000 feet MSL, never venturing above to watch the ambient pressure decrease requiring more throttle to maintain a climb or cruise at 8 to 12k feet until you're at full throttle anyway. I also find it comical that you either can't read and learn or refuse to do either.
 

Tiger Small Engine

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So...you must be that guy that just stays below 3000 feet MSL, never venturing above to watch the ambient pressure decrease requiring more throttle to maintain a climb or cruise at 8 to 12k feet until you're at full throttle anyway. I also find it comical that you either can't read and learn or refuse to do either.
We went from outdoor power equipment, to airplane engines.

Most of the push and self-propelled mowers I check RPMs on, are running from 2800-3000 RPM. I bump it up to about 3150.
 

Scrubcadet10

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This question was practically answered on the 1st page. It's served its purpose. Now we're on to airplanes....on a lawnmower forum.
 
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