I throttle down some in dusty areas. The only possible problem I see is cooling. The flywheel fan on top of an air cooled engine will be turning slower and moving less air. But, the engine should be a little bit cooler anyway. I'd like to do a test with an infrared thermometer to see the difference in engine temps at WOT and less than WOT.

 

I came home today and the old guy next door was mowing on his rider and it was very very low speed. One thing was it was quite.

 

Well cooling is very important and running wide open keeps the engine cooling better and the oil circulating...The hydro pumps probably need wide open too

 

Mower engnes should always be run wide open.

I've done the infrared thermometer test and the engine actually runs hotter at half throttle than at full throttle. Runs coolest at idle for some strange reason as that's when it has the least airflow, but the load is negligible also.

 

Mower engnes should always be run wide open. I've done the infrared thermometer test and the engine actually runs hotter at half throttle than at full throttle. Runs coolest at idle for some strange reason as that's when it has the least airflow, but the load is negligible also.

At low throttle it'll overheat the most always run your engine at full throttle to keep it nice and cool your blades are designed to spin at your manufacturer's recommendations which is 3600 rpm to kick crap out your discharge chute

 

Yes, that makes sense with cooling issues and all. Its 102 here today and I sure would not want to risk overheating an engine or pumps. Thanks!!

 

No always run your Engines at Full throttle. The engine and transmission need to have the RPM's to keep the oil Film on the bearings and other internal parts. This is what I have always been told.

 

I lower the rpm's in sensitive or dangerous area's regardless. Very rocky soil in some area's and I use care when the chute is pointed at something like an expensive window or car. I can buy and engine for the price of some things that could be damaged. The power chute helps a lot in these area's. But even with the chute blocked I want to minimize the chance of damage to certain area's of liability. Not to mention if you are cutting commercial and there are people near by. I'll take my chances lowering the rpm's for short periods of time in those situations. Take a 24 hr a day business. When are you going to cut and trim when there are no auto's or people. Never. Best to lower the speed of the engine and trimmers in my book. I know I'm going against conventional thinking but that's the way I'm going to do it. I sure can by a trimmer cheaper than an expensive window or paint a Mercedes. I'm not talking about running around for an hour with the equipment at half speed, just dangerous area's. I do things according to my best judgment.

 

So a rock flying at a Mercedes at 90mph instead of 120mph makes a difference??

 

I cant run my toro wheelhorse at less than full throttle otherwise the blades start to make funny noises. and i think it might ruin the engine if i run it low at throttle.

 

No you should not run your engine full throttle or ‘wide open’ all the time. This can cause unnecessary wear on the crankshaft and rods. Your battery can charge just fine at 1 quarter or half throttle. While running an engine at full throttle can cool it better it decreases the life span of the engine. It also causes the engine to get hotter than it needs to be, when the engine stops running oil can get dirty much faster and sometimes start to evaporate bc of the eminence heat created. It creates more wear on the crankshaft and connecting rods. The reason mowers have the ability to go wide open is for t̲h̲i̲c̲ g̲r̲a̲s̲s̲/̲t̲a̲l̲l̲ g̲r̲a̲s̲s̲. After a year of a engine running full throttle will wear the crankshaft to the point where there is play on the rod(s), this will cause a knocking sound. Beyond this point if the engine is still ran full throttle during operation the crankshaft will be beating on the connecting rod(s) due to space between the two, this will wear the rods even more eventually causing the rod to snap bc it got so thin. You can expect 2 and half years of life, most people prefer this as engine abuse or disrespecting said machine. It is not recommended to run your engine at full throttle unless you are in tall/thic grass.

 

No you should not run your engine full throttle or 'wide open' all the time. This can cause unnecessary wear on the crankshaft and rods. Your battery can charge just fine at 1 quarter or half throttle. While running an engine at full throttle can cool it better it decreases the life span of the engine. It also causes the engine to get hotter than it needs to be, when the engine stops running oil can get dirty much faster and sometimes start to evaporate bc of the eminence heat created. It creates more wear on the crankshaft and connecting rods. The reason mowers have the ability to go wide open is for t̲h̲i̲c̲ g̲r̲a̲s̲s̲/̲t̲a̲l̲l̲ g̲r̲a̲s̲s̲. After a year of a engine running full throttle will wear the crankshaft to the point where there is play on the rod(s), this will cause a knocking sound. Beyond this point if the engine is still ran full throttle during operation the crankshaft will be beating on the connecting rod(s) due to space between the two, this will wear the rods even more eventually causing the rod to snap bc it got so thin. You can expect 2 and half years of life, most people prefer this as engine abuse or disrespecting said machine. It is not recommended to run your engine at full throttle unless you are in tall/thic grass.

I would know because I have over 10 years of experience with motors.

 

In dusty conditions I use sharp blades with no lifters. I rarely use full throttle under any conditions but the engine is liquid cooled. Doesn't seem to bother the engine, 3500 hours on it.

 

Yeah this is an old thread… almost made me laugh when I read through comments

 

I throttle for dry/dusty/sandy areas but not for long.

 

You can run less than governed RPM under light loads. It will save fuel and wear on the engine. just like over drive saves fuel and wear on your truck, but you wouldn't try to climb a mountain pulling a trailer in OD.

As long as the motor doesn't over heat, running less RPMs is fine.

Ed Wright in his video that was posted here about mowing from the makers of the Wright stander, says you can mow at less than governed rpm.

BTW, running at full RPM is the easy fool proof method, you don't have to worry about it. I don't think anyone can argue that running them at full governed rpm will damage the engine.

 

Yup. In fact Exmark mowers with RED technology allow you to run the engine at different RPMs for different conditions. I don't think they would do that if it meant you would burn up your engine and hydros.

 

My owners manuals have all stated to run the engine at WOT when mowing or blowing snow etc. No, you don't need WOT for tooling from one place to another or for going from front to back yard, nor even for towing a trailer around your property etc., but that is not what we are talking about here as far as running your engine at WOT while mowing. Running them below WOT under light cutting conditions will not harm anything on the engine really, but it just might cause more harm than good for your hydros which are designed to be cooled most efficiently by their fans with the at WOT.

When I say my pwners manuals, I am talking all the way back as far as 1969 manuals for JD and Jacobsen garden tractors that utilized single cylinder Kohler/Tecumseh/Wisconsin engines, which were very basic in design compared to today's engines.

 

Modulating engine speed for certain conditions (wet grass, sandy/dusty conditions etc) had been an SOP for multiple operations country wide since forever and had never done any damage to anything worth mentioning.

 

It's always been 'pedal to the metal' for me.......

 

 

let's please stick to the discussion at hand...there is no need to attack anyone personally, call someone names, degrade them, nor talk down or in a derogatory way to another member

thanks!

 

Most experienced/knowledgeable operators run their mowers full throttle in wet grass at a reduced ground speed.

 

No
They don't
Why don't you read some of the threads on this very site about cutting in wet grass and clumping.

the BTS of some of the modern mowers are much higher than they once were
Depending on your grass type and what deck type you have this is just causing a deck packing problem that keeps up all day long.
Causing people to rant and rave about this machine or that machine not working.
If the conditions are different than normal and you aren't getting the results you want or expect, try different things.

of course most people drive faster and crazier when it's raining or icy, so must people do exactly the opposite of this.

most experienced operators does mean "this is what I do", you aren't most experienced operators

now if you wanted to say "most hourly employees that don't know any better or care" then that would be accurate.
When you go back later in the lawn after it's started to dry and find all the smushed in mow muffins that will be rotting turds by next week, that's due to the mower running full power literally making vegetable grass smoothies
Operators don't notice if
It camouflages in with the lawn when wet and often gets run over after it falls from the deck.

thar chum you have to chisel off the deck with a Putty knife after it's dried and caked in there?
Yea
That doesn't all stay on your deck when you're cutting.

if/when you drop your BTS a bit , that vegetable smoothie doesn't happen
It's more of a salad
Easier to clean up and notice as it isn't made into a milk shake.
Far easier to cut the lawn a second time and not make such a mess than try to mow at max power and either clean your deck every other pass or make the problems I mentioned above.

most experienced operators have known that for years

 

Unless you have an electronic governor, your engine cannot respond to varying load unless it is at WOT setting. The throttle setting you set is going to be the power you make, no more than that, hit a patch of thicker grass, your RPM drops.

 

Old thread but I’ll put two cents in.

i use the throttle as a tool all day every day. As much as i use my sticks. Throttling down still cuts fine because the ground speed slows in relation to fpm.

 

I reduce throttle on my own lawn depending on how much growth there is and what time of year it is. It's a front mount JD with a kawi motor on it and it still cuts fine at 3/4 throttle which is generally what i will run it at when i'm trimminmg and cutting slow growth.

 

Everyone has opinions on all things associated with life. Do what you feel is best for your situation based on your ability to think, if what you think works best for you then go with it, if not correct you will learn from the negative experience you will eventually deal with. This is a learning curve that only comes with experience.

 

I don't mow wide open unless necessary. What I do is keep the fins clean of grass and dust on the cylinders. Remove the shroud and blow it off with compressed air from time to time.

 

Chiming in late here but I'll add that during the summer months, I always mow at full throttle. However, this time of year during leaf cleanup, I reduce my throttle to about 5/8 and run slow to maximize pickup and reduce blowout. I can't say whether or not this is harmful to the engine or hydro system but I'm hoping cooler temps, low ground speeds etc offset any potential damage.

 

The efi motors with the exception of the Kohler red tech are designed to run at 3600 rpm and the efi is programmed to keep the rpms there under various load conditions. That is why you burn more fuel under heavy conditions as the throttle body gives the engine more fuel. I can't imagine too many times where you would want to slow the engine and blade tip speed down. Lugging an engine is hard on it like driving a car in too high of a gear. When towing I put my truck in tow/haul mode to keep the ecoboost in its optimal power band. It reprograms the 10 speed to keep the engine from dogging down.