Run at Full Throttle?

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TJohnD

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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?
 

7394

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Yes full throttle for air cooling of the engine, but also if you have hydro trans, they need the revs to run proper with the fluids.
 

MParr

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When the engine manual say run at full throttle, there are reasons for that. Engine cooling is one reason. Maximum rated horsepower being reached at full throttle is the other.
 

Tiger Small Engine

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When the engine manual say run at full throttle, there are reasons for that. Engine cooling is one reason. Maximum rated horsepower being reached at full throttle is the other.
Wide open throttle.
Period.
Do some additional research and reading as to why if you are interested. Older men are notorious for running equipment at say 3/4 throttle.
 

MParr

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Wide open throttle.
Period.
Do some additional research and reading as to why if you are interested. Older men are notorious for running equipment at say 3/4 throttle.
This doesn’t apply to me. I always run at full throttle. My Gravely was delivered running at 3,300 rpm at no load. I adjusted it to run at 3,600 rpm with no load.
 

StarTech

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And we all do a cool down of the hydros. Personally I replace to many plastic fans especially on the Hustler Raptors. I got to where I just stock them and the drive belt they break.

Running them at lower speed just allow the blade to heat up, curl up and set, continue to do this each time until they get into belt path.
 

bullet bob

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And we all do a cool down of the hydros. Personally I replace to many plastic fans especially on the Hustler Raptors. I got to where I just stock them and the drive belt they break.

Running them at lower speed just allow the blade to heat up, curl up and set, continue to do this each time until they get into belt path.
Hmmmm, first I've heard of this. How do you do this?
 

etbrown4

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At full throttle the engine is not wide open because for the last 75 years all modern engines have used governors. A governed engine is running 500-800 rpm below what would be wide open. You can relax, and don't give a thought to plastic fans.
 

StarTech

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Hmmmm, first I've heard of this. How do you do this?
Air pressure and plastic softening on the side next the hydros so it stretches.

And apparently you have never work on Hustler Raptors. I am constantly replacing fans on them when drive belt are broken along that little 2 inch idler pulley that bearings are failing in.

And I came across a new problem to compound the problem transaxle mounts breaking. Loose screws was bad enough now the brackets are breaking too. Hustler is selling a beefed up repair kit but should be doing a recall instead. Of course these are out of warranty unit so they don't care.
 

thesilentone

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We don't always run full throttle when mulching in damp conditions. As long as the cut is good, we run as slower engine speed as possible, we find the deck clears much better than flat out.
 
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