2 cycle vs 4 cycle

Discussion in 'Shop Talk' started by gwithrow, Apr 8, 2006.

  1. gwithrow

    gwithrow Well-Known Member

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    what is the difference in these two engines? and which one is better? in a small tiller? I know the weed whacker and the chain saw are both two cycle, and the mowers are 4...but is there an advantage of one over the other? thanks..gw
     
  2. jefferson

    jefferson fuzzball in the Cascades

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    power to weight..2 cycle packs twice the punch. Power on every turn of the crank. 4 cycle power on every other rev. 4 stroke has the longivity.
     

  3. Cabin Fever

    Cabin Fever Life NRA Member since 1976 Supporter

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    I'm not so sure that 4-strokes have the longevity. I know of two 2-stroke LawnBoy mowers that are more than 25 years old that are still going strong. One of the mowers is mine.
     
  4. Columbia,SC.

    Columbia,SC. Thats MR. Redneck to you

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    Less gas, less noise, straight gas, not as loud, but more difficult to tear down to work on but I lean towards 4 stroke my self.
     
  5. Beeman

    Beeman Well-Known Member

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    A 2 cycle engine has less moving parts, is lighter, has no oil resevoir, needs oil mixed with the fuel for it's lubrication. They are usually high revving low torque motors. Because they have no oil resevoir they can be operated in any position and at any angle. A 4 cycle engine has more moving parts, has an oil resevoir but uses straight gas as oil resevoir does the lubrication. Can only operate in upright position and is heavier due to more moving parts and larger parts to withstand higher torque.
    Each has their purpose but 2 cycles are being looked at hard for pollution.
     
  6. dodgetkboy78

    dodgetkboy78 Active Member

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    If you are going to use your tiller a couple hours a year, I would get a two stroke, as stated before, they have more power for the weight, and dont have any oil revervoir.
    Which means no oil changes, no worries about it getting tipped over..................They start good too, better than a four stroke if they are inj good tune.
    If you are going to use your tiller a lot, get the four stroke, they are quieter, more eficcient, and should last longer. (requires more mainenance though)
    I agree on the lasting shorter comment, my 98 Polaris has 16,000 miles on it, and I am still waiting for it to blow up.......(runs like new)
     
  7. gwithrow

    gwithrow Well-Known Member

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    ok let me get this straight, the 2 cycle tiller would be lighter, and for using in the raised beds this would be good, we will not use it constantly, probably just to get the garden plots, in raised beds, going every spring and again in the fall to till in the mulch...and there is a hundred dollars difference ...the 2 cycle being cheaper...I will go and look them over again and see if they are constructed similarly, I do not want to buy a piece of junk that will only last a year or so...Sears has both of the ones I am looking at...though any other suggestions would be welcomed...thanks gw
     
  8. Beeman

    Beeman Well-Known Member

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    2 cycle tillers are usually small and light for tilling between rows or in flower beds. they are more of a cultivating tiller like a Mantis. they could easily be lifted into a raised bed, but I don't see the need for a tiller in a raised bed. 4 cycle tillers are the larger tillers used for completely tilling a large garden and will till much deeper in the soil.
    I have seen Stihl 2 cycle tillers at the store and would be inclined to buy one of those if a small lightweight tiller is what I was after.
     
  9. Oxankle

    Oxankle Well-Known Member

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    I have a Troy-Bilt four cycle tiller and it is hardly heavier than the Mantis it competes with. Every bit as versatile but as stated, it cannot run upside down.

    I have run both 2 and 4 stroke lawnmowers and edgers. Best edger I ever had was a Jacobsen 2 stroke. Generally you do not see a lot of large 2 strokes--all outboards, even the military 50 HP's that powered landing craft, were once 2 stroke but now I see only small 2-stroke engines.

    One word about present-day 2 strokes: They are down now to a 50:1 ratio of gasoline to oil. I believe this ratio is dictated more by environmental and regulatory concerns than engine life. True, engineers have learned to direct the incoming fuel spray to bearing areas, but even so 50:1 is pretty dry.

    Long ago when we used outboards to make our living my dad told me that a richer fuel would prolong engine life--in those days we were running a quart of oil to 4 gallons of gasoline, l6:1 mix. Those old engines were greasy, smoky and plug-foulers but they never wore out. The magnetos would generally quit before the bearings. Today when my chain saw calls for 50:1, I use 32:1. Sure 'nuff, when my old dirt eating brush saw quit last week it was the fire that died.
    Ox
     
  10. swamp man

    swamp man Well-Known Member

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    I was wondering about the little stihl tillers.Are they still 2 cycle?Lotsa' the stihlstuff has gone to their "four-mix" engines(a four stroke engine that uses mixed gas),and I'm not too crazy about them.I have a tiller attachment for my old two cycle stihl trimmer,and it works well.The only thing I dont like about it is the high rpm's the tiller turns.It really slings the soil,and would be difficult to use in a raised bed without tossing lots of soil out of the bed.
     
  11. dodgetkboy78

    dodgetkboy78 Active Member

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    Always use the recomended oil mixture, using too much oil will cause carbon build up, and detonation. Engine design, and new oil quality is the reason for the leaner mixture of oil. Running too much oil kills them quick.