(Scag) kawasaki Fc420v swap???

Discussion in 'Mechanic and Repair' started by flattoplawncare, Jun 3, 2007.

  1. flattoplawncare

    flattoplawncare LawnSite Senior Member
    Messages: 321

    :usflag: Hello I have a Scag sw48ka belt drive walk-behind i think it is a mid 90's and i am wanting to upgrade the engine right now it is a recoil start (actually i rap a rope around where the recoil used to go) but anyways i want to know what engine i can just unbolt/bolt on. The blades are manually engaged and there is nothing electric on it. I want a 17 hp or maybe even another 14hp recoil start. what engine's do you know of that i could just swap out? any help would be greatly appreciated thank you.:usflag:
  2. khouse

    khouse LawnSite Bronze Member
    Messages: 1,465

  3. ctyyoung

    ctyyoung LawnSite Member
    from Tulsa
    Messages: 1

    I ran the exact same engine on my Scag hydrostatic drive out of oil and should receive a Kohler 15 hp Command engine in the next day or two. Tulsa Engine Warehouse or any similar engine supplier will supply you with the correct engine or, in your case, an upgrade.

    As you may know, the Kawasaki engine that you have is no longer available. That's okay, I wasn't too impressed with the FC420V to begin with. Mowing with 48 inchs of swath out front the little Kawasaki loaded up at times. Kohler offers an 18 hp Command series engine that may or may not fit. It might seem like I'm pushing Kohler but that's not the case. Kawasaki makes a fine engine as does Honda, Onan, and a few other small engine manufacturers. You should be able to find an equivalent or upgrade from any of the engine makers.

    The actual wrench work is easy. I pulled my old engine in ten minutes and a half a beer. I anticipate the install will take 30 minutes. Next time you walk into your local Scag dealer thank the Almighty for making a stinky mower that works and you can work on!
  4. dartland

    dartland LawnSite Member
    Messages: 21


    I have the dreaded and much-debated surging problem on my Kaw FC420V on a 36" Ransomes Bobcat walk behind. This engine is 30 yrs. old, and has done well, but is unusable at the moment. The mower it powers is in fine shape; I only used it to mow a large lawn once a week where we lived for about 20 years.

    Don't want to throw out the mower, but I think the best thing to do here is re-engine the unit. Anyone know of a good replacement for this Kaw, or where to send me to find an engine that I could drop in, plug and play as much as possible? This engine was no world-beater to begin with, and more horsepower would be desirable.

    Thanks for your help.
  5. Walker56

    Walker56 LawnSite Fanatic
    Messages: 5,140

  6. dartland

    dartland LawnSite Member
    Messages: 21

    Thanks; will give them a shot, and will report the results.
  7. The Green One

    The Green One LawnSite Member
    Messages: 7

    Hi Dartland,

    Did you ever try running the unit with the air cleaner cover off, in a clean environment of course, to see if the surging stopped?

    I know of a time when an Intake Valve was not seating correctly on a FC420, and those extra pressure pulses, had a negative impact on proper carb function. The engine surged.

    Worth a shot.
  8. dartland

    dartland LawnSite Member
    Messages: 21

    I've heard about that issue, and will certainly give it a try.
  9. Walker56

    Walker56 LawnSite Fanatic
    Messages: 5,140

  10. dishboy

    dishboy LawnSite Fanatic
    from zone 6
    Messages: 7,110

    Generally lean surge is either crap in a fuel passage or a intake leak. A lot cheaper to fix your mower if you have good compression and are not a oil burner. IMO a belt drive is not the place to throw good money, you have a $200.00 mower in its present form. Buy a hydro .
    Kohler confident 21 hp is your best repower IMO$1050 with a muffler at your local dealer.

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