Mowing, full throttle or half?

[Jasen 10]

So I have a question. I'm used to running junk big box store mowers. The kind where I had to run them at full throttle to keep the deck going fast enough to cut grass. I noticed though that with my 310-8, it seems to do just fine at about half throttle. Is mowing at half throttle ok? Or should I be running it wide open? I don't usually let my grass get more than 4-5 inches high before mowing.

[doc724 925]

Wide open.  Remember, you are not just cutting grass, you are cooling the engine as well.  These engines are designed to operate at WOT.

[Sparky-(Admin) 22,083]

Doc's right about the cooling part......and full throttle is better for your splash lubed motor.

Mike............

[WH nut 553]

Wide open, 3600RPM

[Wheel-N-It 2,971]

Jasen, don't be surprised if you get differing opinions. I respect them all. For mowing and I run them wide open. For pulling a trailer or just driving from point A to point B, I run about 3/4 throttle or a little higher.

[cleat 7,030]

I don't think I have ever run my tractors at full throttle, maybe 3000 RPM to mow, less to drive around. I have ran my Ford LGT165 this way for years. My larger diesel tractor never sees over 2000 RPM.

 

Cleat

[pacer 3,175]

I'm like Cleat, I rarely run my tractors WO. For general grass cutting I run at (guessing here) 2000-2200r's For putting around the yard maybe 800-1000r's. My 1975 D-100 has led an active and productive life for all these years being run that way and it doesnt smoke or use oil - I do keep a watchful eye on it, chaff build up, oil changes, etc. I've also got a big box '92 Yard Man and it has really gotten used, along with grass cutting, it runs the Cyclone Rake vacuum, same story here, no smoke no oil use, runs like a top.

[Jasen 10]

I was just curious. I know my grandfather used to always say, don't run a horse hard unless it's working hard lol.

[Jasen 10]

Come to think about it. He used to always tell me that when I was running his Wheel Horses wide open around the pasture!

[DoctorHfuhruhurr 137]

Anyone have one of those infrared temperature guns?  I'd be curious to see what the temperature differences were (if any) at full and partial throttle.  Although that doesn't address the lubrication issue; it may be useful to know to settle the temperature debate (or not).

[km3h 543]

All due respect to those who run less than full throttle, but every small engine manufacture states in their literature that it is to be operated at full throttle at all times. Many of these engines do not have oil pumps and get lubrication from a splash. The faster the splash the more lubrication. The faster the flywheel turns the more air circulates to cool the engine. When you turn three blades as fast enough to cut grass it takes a lot of horsepower. Remember that the blades have an upward curve which uses energy and causes air resistance.   

[km3h 543]

I don't think I have ever run my tractors at full throttle, maybe 3000 RPM to mow, less to drive around. I have ran my Ford LGT165 this way for years. My larger diesel tractor never sees over 2000 RPM.

 

Cleat

I also have a Ford LGT 165. Since it has a single cylinder 16 hp Kohler engine, RPMs are not as critical as they are on the twin cylinder Wheel Horse engines. In the Wheel Horse design, the rear cylinder is always starving for cool air. Especially the Onan engine. Your 16 Kohler has a rod with an extension on the bottom that dips down into the pan and helps splash oil to the rest of the engine. My guess is that your diesel is water cooled.   

[Mike 6]

73 auto 14 hp I bet a guy at work this years ago. mines still running and his is  long gone.  Higher RPM means more heat also. I run mine little over half...keep the oil changed.

[876wheelhorse 46]

Oil slingers more rpm more they sling and better for motor

[js5020 111]

Full bore, keep those blades spinning, force max air over the engine and hydro, keep max pressure at the hydro, and keep the power blower spinning.

[km3h 543]

73 auto 14 hp I bet a guy at work this years ago. mines still running and his is  long gone.  Higher RPM means more heat also. I run mine little over half...keep the oil changed.

Another single cylinder. Evan so the book says full bore, 3600RPM for a reason. You think they want you to simply waste gas? I will always follow the manufactures instructions. The engineered the engine and know what is best for it. 

[shallowwatersailor 3,214]

Jasen, don't be surprised if you get differing opinions. I respect them all. For mowing and I run them wide open. For pulling a trailer or just driving from point A to point B, I run about 3/4 throttle or a little higher.

This is my opinion as well.

[kaiser 100]

full throttle and let the gear determine the speed.

 

the only tractor i run at partial throttle, and only occasionally, is my 48 farmall.

[Road-Track 39]

Some WH manual say 3600 on Kolher singles and the C series manual says 3400 RPM. Since I added Tachs to the herd. I run at 3400 WOT.

[Molon_Labe 731]

I've always adjusted the throttle to the job, from putting around with a garden cart to full bore when plowing. It's always worked out whether it's right or not according to the manufacturer.

[tbarnhart 240]

I don't get not running at full speed for cutting grass. Here in GA, our grass gets dry and tough and even with sharp blades can be hard to cut unless you drive slow.  I wanted to be able to cut grass in high 3rd with my 160 so I upsized the pto pulley to spin the blades faster.  I set the high idle speed to 3600-3650 with a tach and keep it that way when mowing. For other lighter jobs, its set to give enough power for what I'm doing. As far as splash lubrication in these motors, I can promise that there is plenty of oil flying around inside at the 1200 rpm idle speed if the oil is full. Imagine dipping into the oil 20 times a second. Oil everywhere.

[Geno 1,929]

I also wouldn't think of not running full throttle to cut grass.  I also know most manuals say to run higher RPM's but I never have, only for cutting.  I guess I would for tilling or snow blowing but I haven't done that yet. I wonder if the high rpm thing is just when they're working and under load, and is the high RPM for oil, or air to dissapate the heat?  

 

If I'm using one around the yard it's lucky if it ever gets to 1/4 throttle, and idles plenty.  I figured also that there was plenty of oil slinging around in there.  The 414 has been in the family for 27 years and that's how it's been used since it was new, it is completely quiet and there is zero oil use between changes. 

[C-85 726]

Like others have said, I have a lot of respect for the other views on this.

 

My take on this is different than many views though.  I don't run any of my engines at full throttle unless I need it for power or speed.  I have thought that yes, more cooling and lubrication happens at full throttle, but at the same time I've felt that the higher speed demands this, and by running the engine slower it doesn't need so much cooling and lube.

 

Recently I was talking about this subject with one of my old beloved neighbors, who is 88 years old.  He summed this up in different words than I ever thought about this, he said "ya know, these engines are only designed to spin around just so many times, so why subject them to higher speeds when you don't need to".

 

This kind of confirmed for me what I've always thought, that running engines full blast, may make them wear out faster.

 

I know this defies some of the logic, but I'm going to stick with only using as much speed and power as I need to do the job. Maybe this will make my equipment last a little longer, save a little fuel and possibly pollute a less.

 

C-85

[WH nut 553]

When in doubt read the manual

[Jasen 10]

Wow! I didn't mean to cause a big debate on this. Sorry guys.