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Full throttle for all operations?

  • Yes

    Votes: 73 46.5%
  • No

    Votes: 84 53.5%
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Discussion Starter #1
Regularly I see mentions of "how much power my tractor has pulling at idle..." "I was only running half throttle when pulling the plow" "I engage my mower deck at idle to prevent broken belts" etc

I am interested in how many people operate their tractors at less than full throttle and why. I looked at my Kohler Courage 26hp motor and see that peak torque is a little above idle, but I don't see anywhere in the manual where it mentions running at anything less than full throttle.

In my case, whenever the tractor is moving, I have it at full throttle. The only time I allow the motor to idle is right before I shut it down (which is against what Kohler says, they say to shut it off at half throttle)

Chris
 

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Retired Aug.31 2007
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I run mine at full throttle due to being a hydro. If it was a manual there would be times that I would not run it at full throttle.
 

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15,000 +posts!
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I run my MTD at full throttle,the hydro doesn't pull as good otherwise,and I feel an air cooled engine lives longer with the RPM's up near the rated maximum,as more air is blown over the cooling fins,and also the oil pressure (on engines with a pressurized oil pump system) is also higher at higher RPMs..

I have "putted" around on my tractors with manual trannies though,without any apparent damage,and see no need to run them much higher than 2500 RPMs or so,they seem to have sufficient power at that speed,and the govenor will kick in anyway,if more is needed..sometimes you cant take off smoothly when the engine is going 3600 rpms with a manual tranny,you'll end up popping a wheelie!..it beats on the belts and tranny too,dumping the clutch at full tilt when there is no need too..
 

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Kind of a useless poll if asking about "ALL the time". I run full throttle 98% of the time so I had to vote NO.

I don't start the engine at WOT.
I idle it down before killing the ignition.
I engage the PTO at half throttle.
I don't run it WOT inside the shop, driving into or out of the shop, or when shuttling around to hook up implements.

When the tractor is working however, it does so at WOT.
 

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Interesting how more people voted YES. Do you guys start your engine a WOT? Shut it off at WOT? I cringe thinking of the damage a splash lubed engine suffers going to WOT on a cold start.

If the manufacturer wanted WOT "ALL the time", they wouldn't have bothered to put a throttle control on it.
 

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Discussion Starter #7
Kind of a useless poll if asking about "ALL the time". I run full throttle 98% of the time so I had to vote NO.

I don't start the engine at WOT.
I idle it down before killing the ignition.
I engage the PTO at half throttle.
I don't run it WOT inside the shop, driving into or out of the shop, or when shuttling around to hook up implements.

When the tractor is working however, it does so at WOT.
I should be more clear, who runs full throttle when the tractor is moving.

As far as damage to a splash lubricated engines going straight to full throttle when cold, I doubt it. I have too many Honda and Briggs engines in my possession that only run at one speed, full throttle.

Chris
 

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Interesting how more people voted YES. Do you guys start your engine a WOT? Shut it off at WOT? I cringe thinking of the damage a splash lubed engine suffers going to WOT on a cold start.

If the manufacturer wanted WOT "ALL the time", they wouldn't have bothered to put a throttle control on it.
My Bolens 14 is a 1987 tractor and the throttle has been used so little that,right now,it isn't working,I've owned the tractor for 9 years.It's a 14hp B&S 400707 engine,the tractor is hydrostatic drive,I start it at full throttle,and as I mentioned in a previous post B&S used to recommend that an engine with a splash oil system be brought up to operating speed asap after starting.It takes me about 45 minutes to an hour to mow after which I shut it down from full throttle,I used to idle it down some and it backfired everytime that I did,so now I shut it down from full throttle.It usually takes me a couple of minutes to get from where I finish mowing to where I park the tractor,so the engine does have that much time to cool down and I very seldom mow in the hottest part of the day,usually in the evening when it's hot out but I live in western NY so our hot is usually only in the 80s.If this weren't a hydrostatic tractor,it would probably be throttled more,when I use my Bolens 900,it usually is,except when I'm blowing snow.Even that tractor,when it's working is at full throttle.
 

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JD Green all the way~!
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For my 300 with a 16hp Kohler, I will start it at around 1/2 throttle, and once its running go ahead and push in the choke, and open up the throttle some more when I am just moving it out of the garage. Once out, and before I am ready to start work full throttle she goes.

Makes since that you want to run one like mine full throttle, cause like said above its air cooled, and the fans really do move some air for both the engine, as well as for the transmission.

Before I shut it down, I will let it idle at 1/2 throttle, or less for a minute or two then go ahead and shut it down. Why? I don't know...many always recommended doing that every time, so I am taking their advice.

~F~
 

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AKA Moses Lawnagan
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For mowing and ground-engaging work, yes, I run mine at full throttle, and also if I'm pulling a load of more than a 100 lbs or so. It's harder on the HST than the engine to work it at partial throttle, because the tranny may not be working at full pressure with the engine at less than full boogie. Basically, the engine is just spinning a pump, and the HST is doing the work, and must be at its rated pressure to perform well.

If I'm just driving around from place to place, or have a light load, I still run at about 2/3-3/4 throttle. I always start up at idle, then advance to about 1/4 and let the engine warm up about 30 seconds, get everything circulating. I always drop to idle and let it run 30-45 seconds or so before shutting it off. That's more a habit from driving a turbocharged diesel truck, to allow heat to get carried out of the turbo bearings before shutting down.
 

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Guess I'm in the minority here, I start mine on a fast idle and leave it there till I feel warm air blowing out the grill. Now that's on an old Kohler K engine and my Onan. Once warmed up I run them 2700-2800 rpm's (I have tacs on my tractors) for mowing or tilling or etc. If I'm just pulling the lawn sweeper or roller, etc I run them at about 2000 rpm's. Guess it works, the Onan has over 2500 hrs on it and the two Kohlers are 1982 models still going strong, don't burn or leak oil and plenty of power.
 

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Snapper Lover
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The snappers run at WOT when I'm mowing but the one hunts really bad when not under a load so I ususally half throttle it when I"m just driving around to empty grass etc. The Cub rarely runs at WOT. I just use it mainly for the blade and pulling things around. It's too fast with throttle open and way to loud!

T.C.
 

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I fire up my 26hp Kohler at idle. The manual says to let the hydro warm up for a minute or so, depending how cold it is out side. I was always told never rev an engine until it gets to operating temp and all the metal pieces expand to their correct clearances. I idle it down at shut down or I get the big backfire.
Same goes for my 16hp Briggs in my 990, the engine and hydro gets warmed up before being put to work and if you don't idle it down at shut down, that Briggs will go boom like a 357 mag.
 

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I mowed this big lawn for a Napa auto parts back 16 years ago. I only had a Snapper 21" commercial wb with a Robin commercial 4hp 2 stroke. The lawn took me about 1:32 to mow. The grass was not very thick. Since the disc drive on the 21" wb were much like a hydro I did some experimenting and throttled the engine back and turned up the drive disc speed. I went from using 1-1/2 small tanks of gas to just one. And my mowing time did not change.
 

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Landscaper
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Always run my 604 at full throttle. Previously i used a Kubota g21...again always at full blast.

But also used a huskie zero-turn mower, had to engage the blades at half throttle, otherwise the belt would pop off. Used to forget sometimes, a right devil of a job to put back on.
 

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an effin canadian
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no. not all the time. (my tractor is used for winter only) I run the snowcaster usually pretty close to WOT, but rarely all the way - i just don't need it. when snowplowing, i stick er down to about 1/2 - 2/3. with a gear tractor i have buckets of balls at idle, and being used primarily in the winter, i don't worry about cooling.
 

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Start at idle and set the throttle for the job at hand. WOT for tilling, mowing, snow blowing and travelling down the road. Half to two thirds for loader, backhoe and towing as required. Try running a back hoe in close quarters at full throttle. The faster an engine runs or is loaded the more cooling it needs. Fuel consumption equals heat, low RPM doesn't use much fuel and doesn't require as much cooling. Cold starts are hard on rotating parts, but once the oil pressure is up (about 30 sec.), the fastest way to warm everything up is to burn fuel (work it), or just let it idle for a while depending on the price of fuel and time constraints. Either way works, and experts can be found to support both. Hydrostatic transmissions only build enough pressure to do the job being done at the time and only make appreciable heat when they are working. The only way to warm them up at 20 below is to work them. Throttle back when parking and shut down at part throttle. I don't run my truck at full throttle all the time either.

Works for me.

Bob
 

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The Magnificent
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I have to agree with lligetfa on the poll choices not reflecting actual usage. I think you are assuming most people have an air cooled consumer grade engine. The fan in my Onan is big enough that it moves more than enough air at lower RPMs.

I start mine at idle to 1/4 throttle and get it off choke as soon as possible. I will then go to about 1/2 to 2/3 throttle to move the tractor around to whereever I need it. Full throttle for mowing, plowing, and using the loader. Other tasks I do at a lower RPM.

After a serious workout, it runs full throttle for a minute or two, then down to idle for a minute, when the fuel valve is closed and the carb is partially drained before shutoff.
 
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