full throttle?

[pinecone 26]

newbee wh 312-8 this year and quite pleased. i was looking at new and old listings here and there about oil changing. would like to do it myself along with all the required maint.. being 65 and never changed the oil or a plug in anything i ever owned (mowers, snow blowers and the works), always ran great, will be a reward. renewed when the wheels broke off for the second time. not many hours on the oil but will try to do it right. the real question i have is the articles i read about oil temp.. most sugested running at full throttle to keep the oil cool as more air passes over the engine with other benifits. high revs, more air. - I figured more revs-equaled less engine life. i putt around at 2/3 throttle and do fine even with higher grass. am i doing anything wrong with this approach?

[rmaynard 14,922]

More important for keeping the engine cool is a little yearly maintenance to remove grass clippings, mouse nests, and other obstructions from under the engine shrouds, and cylinder fins. Got to keep that air moving. But man, change the oil once in a while.

[Wheel-N-It 2,967]

I've always done pretty much the same thing. I first run the throttle wide open, then back it down just a tad. Its always worked for me, with never a problem. I only run the engne wide open for work when I have to.

[toolmaker40 6]

i was also taught to idle the engine all the way down for a few seconds before turning off, dont shut your engine off at a high idle leaves unburnt fuel in the chamber and valves

[Tankman 3,515]

After every mow, I vac or blow the screen (air in) out.

Clean the deck.

My Horses are indoors, after each use clean the air circ and mower deck.

I often park the Stallion being used with the hood up, a reminder to check

the :wh:'s oil level before next outing.

I'm 65, retired, plenty of time on my hands. :smile:

[boovuc 1,090]

Wheelhorse/Toro and most manufacturers will stress that the recommended way to run your small engine equipment and especially your tractor is to run it at full throttle. This results in the recommended cooling and lubrication of the engine, the correct implement speeds off your PTO and the proper RPM's for the transmission. (Especially hydros).

Not running at or very near full throttle simulates lugging or drag on your engine, transmission and implements. Picture this....................it's a hot day and high humdity so you mow your grass with the throttle half way open. Without your engine running wide open, you are not achieving the horsepower the motor is rated at. You are turning a mower deck that is not rotating at the RPM it was designed to run at and thus is not cutting the grass efficiently. The transmission is dragging since it too isn't turning the RPM's it's rated at causing an effect not unlike being driven uphill or under a heavier load and the biggest thing is you are not providing the cooling air passing through the engine's cowling to disipate the heat the engine is creating. Over time, this will kill the engine more so than if you just run the motor at full throttle when you are doing any kind of work with it and that includes simple moving from point A to point B.

[MalMac 1,328]

boovuc is right on the money. The engines are designed to run at full rpm and so are 98% of the attachments. Like said if your not running at 100% or close to it, you are not doing that engine any good. Also cause more wear on the the attachments. Take a mower deck for example. The blades have to achieve the designed rpm to accomplish what they are designed to do with the most efficiency. They cant do that ruining at less an rpm than what they were designed at. Unless your governor has been altered to run way up there full throttle is where it will work the best at.

[Martin 2,130]

like others have said, when working these engines its best to run them at full throttle. they are splash lubricated internally and to get the best internal lubrication the crankshaft needs to be turning at full throttle. the connecting rod is the engines best friend, throwing oil to lubricate the internal components.

Edited February 19, 2013 by Martin

[pinecone 26]

tks for the info. will rev it up come summer. guess it time to change the oil on my snowblower and small mower.

[leeave96 487]

I would add a few more comments.

 

When I bought my 314-8 new, I was always wrestling with a low battery and almost got caught in the far corner of the yard with a tractor that wouldn't start.  I was running it at 1/2 and 3/4 throttle.  My FiL also had the same problem with his 520-H, it drove him crazy and unlike the Kohler on my 520-H, he did not have a manual rope starter - so if his tractor died far from the garage, it was a problem!

 

An old dealer straightened me out on that and said the following:

 

1.  Run the tractor full throttle - always.

2.  Use the gears (or hydro) to control the ground speed

3.  If you run at full throttle, you'll never have to worry about your battery.

4.  The engine running at 3600 rpms is good for cooling as cooling is not necessarily linear with the heat load generated by the engine.  The only way to ensure the engine is running cool and be sure of it - is run full throttle.

5.  Max lube internal to the engine is at 3600 rpms - speaking of Kohler splash lube engines.

6.  When you are using the tractor, like mowing grass, and you are tooling around at 3600 rpms, you hit a tall patch of grass, when the engine lugs down, it is likely to go down to around 3200 rpms.  This is the max torque of the engine.  So when you hit a load, running the engine at full rpms/3600 rpms, it set's-up your tractor for when you need power and torque the most.  If you are running lower rpms, you've already fallen off the peak torque curve when you need it the most.

 

The only time I run my tractors less than full rpms is if I'm driving across some gravel and/or a dusty patch of ground when mowing or loading the tractor on the trailer/truck or going in the shed.

 

Thanks,

Bill

[artfull dodger 329]

About the only engines that will tollerate lower rpm work are the Onans, they come from a gen set enviroment and move alot more air for the given crankshaft speed.  Most Onan gen sets run at 1600 or 1800 rpm.  That being said, at lower rpms engines can overheat, blades wont spin fast enough and if hydro drive, you wont get the output pressure from the pump.  I normaly throttle down to mid rpm before kicking off the pto or kicking it on.  Helps save on belt/clutch wear.  After kicking off the pto, I idle down to 1/4 throttle for the short drive back to the garage, then drop to low idle to back into the garage and then shut it down.  Never have issues with back fires ect.  I also dont start it at full rpm, usualy somewhere between 1/4 and 1/2 throttle, but on some with combined throttle/choke controls this isnt possible, so soon as it starts you have to throttle down quickly.  You dont start your car with the peddle to the floor do you?  The Onans have issues with the hardened valve seat coming out of the alum block.  The jury is still out on why, some thought it was the belt guard blocking cooling air on the rear cylinder(one that most usualy has the issue) but real world temp checks proved this to be incorrect. Its my opinion that hard shut downs with no cool down time before shut down is heat soaking the valve area, combine this with out of adjustment valves causing hot spots or overheating the valves would lead to this problem.  Keep the chaff off th, e intake screens on the engine, espicaly Onans.  If your getting lots of chaff coming out from under the front of the deck, why?  is the deck plugged up, rust holes ect.  You can get cylinder head temp gauges on ebay, made mostly for air cooled snowmobile engines, they work on our engines as well.  They have a temp thermocouple that mounts under the spark plug like an electrical ring terminal.  I am going to put a twin needle gauge on my 518 with the Onan twin in it.  Then I can keep an eye on my engine temps.  Cheers  Mike

[pinecone 26]

thanks again all. wished you lived in my town to rub elbows and have a few brews while you give me some maint. lessons. mostly landscaper crews here on the area lawns. zero WH tractors sited. will rev it up full and change the oil every months, prob. will lose some sleep over this. now all i have to do is figure out how to change it. no hints, let me do the down and dirty. i might check back though.

[artfull dodger 329]

Its not to hard, post up if you cant figure it out.  Straight 30wt if it doesnt have an oil filter, otherwise 10w30 or 15w40 in the Onans.   Mike