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Do You Guys Always Mow at Full Throttle?


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I always mow at full throttle. My "lawn" sounds like yours. I always mow after a good rain to deal with the dust.
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If it means anything to you, I always give my wife and kids hell when they mow at less than full throttle. Proper cooling means less maintainance and longer engine life. The only time I mow at less than full throttle is when using a sickle mower because the sickle mowers wont stand high rpms. I hate dust too, but hate costly repairs worse...
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What RPM would you consider to be "full throttle" ???? (I just installed an hour/rpm meter) Firewalling a 19HP to mow grass would seem a bit excessive.
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I just bought a hand held RPM guage (the type with a rubber boot on the end that you place on the end of a moving shaft) and the full throttle speed was about 2500 RPM. Does that sound right to everyone? I have a 1963 MW gardenmark (same as a simp 725). I need to figure a way to measure the RPM of my AC 710 with a 10 hp kohler because the hood gets in the way. John H
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Full throttle should be 3600 rpm. My Sovereign runs around 3450 to 3550 when mowing. Most small engines are designed to run at 3600 rpm max. My 2 cents. Roy
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I don’t have a perfect lawn- grass is thin in places (lots of trees), bare spots, etc., but my Broadmoor owner’s manual says to always mow at full throttle. I know that under maximum loading you need to develop the full hp, and that the deck was designed for optimum performance at maximum air flow, and that proper tranny cooling is dependent on adequate fan speed. But, it would nearly seem preferable, in dry/dusty conditions, with grass sparse and thin, to mow at less than full throttle to minimize creating so much dust- hard on man and machine. My question is, under minimum load conditions, would it hurt or damage the machine to mow at half to three-quarter throttle? What are your thoughts? Thanks.
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Guys, McMaster Carr catalog: Economy (Contact Type) Dial tachometer 0-4000 rpm $54 12" extension shaft for above $20 Vibrating Reed Hand Held Tach 1000 - 4000 rpm range $234 1000 - 5500 rpm range $439 A digital read-out panel mount that uses wither magnetic proximity or photo electric is $143 + sensor proximity sensor $31 Photoelectric sensor $99 The average guy can purchase from them using a credit card, post a reply with your location if you want a phone number for the location near you. From Grainger catalog, Non-Contact Photo Tach Adapter hooks to digital multimeter $109 from 100 - 19990 RPM Anybody got a better idea for my Diesel Magnatrac ?? I was thinking photoelectric untill I looked up the prices.
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I run at partial throttle most of the time. I go to full throttle only in heavy grass. If you have one of the newer engines with an oil pump, you should always run at full throttle. With one of the older flathead, one cylinders that has a slinger type oil pump you do not have to run at full throttle. Rule of thumb: If the engine starts to labor any at all when cutting, give it more throttle. Never lug down an air cooled engine. By the way, the Simplicity/AC decks that I have used are not low profile, high vacuum decks, and they cut fine at part throttle if the blades are sharp. Throttle position is a fine line between wearing it out at full throttle or burning it up at part throttle. If you don't have the feel for what your engine is doing, then, by all means, use "full-throttle" Rod H.
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Rod, I agree with your thinking.We mowed with a B-210 and 48" deck for nearly 20 years.We used approx.3/4 throttle and geared down with the vari-drive in the tough spots.I only replaced the piston and touched up the valves once.That old Briggs is still running fine,although we did retire the old girl last fall due to the vari-drive being worn out. Jim
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This PM was the first chance I have had to try out my new tach/hour meter (1 wire raps around a plug wire). Running a 42" mower with three 14.5" blades, and with my usual speed setting, it registered around 2200-2280 rpm. The 19 hp Kohler Series II was running as fast as I care to run it. The engine certainly doesn't lug, and spins the sharp blades plenty fast enough. The secret is SHARP blades. Better cut, = happy wife. Is the 19 hp overkill ??? I think not. I would rather run a Chev 454 than a Chev 350. Less strain = longer life. Just my .02 cents.
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Rod, Click the link. I got mine at the local lawn mower shop. It's called the Vibratach. Find it at the bottom of the page...Woody[A href='http://www.perr.com/tecstore.html']http://www.perr.com/tecstore.html[/a]
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John H, how much did your hand held tach cost you??I've priced them at local napa and they want over 100 bucks fot one. I have 2 tiny tachs and really don't trust them cuz of thier delayed reaction. Sure would like to find dial tach/hour meters somewhere..MPH
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According to Briggs the top no load rpm for an engine is determined by the length of your mower deck blades. They state that the maximum speed for the blade tips is 19000 feet per minute. Their service manual has a chart for all the different blade lengths and the maximum no load speed of the engine. So what this means is the mower deck determines your maximum engine speed not just 3600 rpm for everyone. Maybe Pocodano no load speed is set too high for his deck. 18"---3800 rpm 19"---3600 20"---3400 21"---3250 22"---3100 23"---2950 24"---2800 25"---2700 This is from Briggs repair manual and I believe them. Safety first!...And I always RTFM...Woody
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John, MPH, The best tack that I have seen, although I don't have one, is the vibrating wire type. We use them at our tractor pulls. It is nothing more than a coil of stiff wire in a housing. The length of a wire determines it's vibrating speed. All you do is set this on top of the engine when it is running, turn the dial till the wire is vibrating to its maximum and read the dial. They work great and you can even use them on your hood and will get the same reading. Next pull (late June) I will try to find out where to purchase, because I want one myself. By the way, I used to turn a BS 10 Hp at 6000 rpm on a pulling tractor and the same engine is now on my AC716 chassis working fine. Rod H.
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That tach really does work Rod. I have one. When I first bought it I thought it was a joke when I opened the box. Looks like parts are missing...Woody
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Woody, Do you know where you got it? I have seen them around quite a bit, but nobody seems to remember where they got them. Every time I ask someone about one at a store, they just give me a dumb, puzzled look, like I'm talking German. Rod H.
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Woody, Thanks for the info. I just ordered one. I got a little worried when I saw the price of the vibrating reed tack in message 13 above. Rod H.
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If I had a diesel it would be hard not to pay john deer whatever they want for the tach they use in the 4100 series compacts. They only go to 2500rpm so not much good on my ole 1 bangger briggs, but they sure are sweet..MPH
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