Replacement Kawasaki engine. STC

Discussion in 'Mechanic and Repair' started by poohboy, Jun 7, 2013.

  1. poohboy

    poohboy LawnSite Member
    from MT
    Posts: 14

    2003 Scag Tiger Cub. Scag STC48A-19KA.
    Looks like it has a Kawasaki FH601V-AS2 engine.

    It does still run. I think it lost oil.
    Put more oil in and it leaks out the top side real bad while running.
    I didn't look under the bottom side yet.

    I took off the top covers and the crankshaft has enough play in it that flywheel is rubbing against the magnetos.
    Are there bearing in these engines or is it only the crank against the aluminum case?

    What are my options for fixing this?
    Rebuild? New block?
    Change engine? Are there other engines will fit without changing out other components?

    How do I get the flywheel off?
    I got the big bolt out but I don't see any threaded holes or an easy way to get a puller on there.
     
  2. pjm123a

    pjm123a LawnSite Member
    from FL
    Posts: 141

    I helped my neighbor who had the exact same problem with the exact same engine. For a while we were going to fix it together then he got frustrated and took it to the dealer. Somewhere north of $2000 the dealer replaced the engine. I ended up getting his old one since the dealer did not seem to care (I would've thought the dealer would want it for something??). Anyway as I recall before the dealer took it we had replaced some kind of seal and had the leaking mostly under control. We took the flywheel off with a 2 jaw puller (the 3 jaw one I had wasn't big enough). If you go the replacement route, I don't think you will be able to get another FH601V. The dealer ended putting in a different Kawi model. I assume it is because the FH601V's are no longer available. There are other engines you can go with (Kohler is one) but some will require you to use different mounting parts. In my opinion you are better off sticking with a Kawi because it will make the installation easier and you will probably have lots of useful spare parts.
     
  3. poohboy

    poohboy LawnSite Member
    from MT
    Posts: 14

    I am having a bad time getting time to work on this properly. It is still out in the driveway and I haven't got room in the shop to set it up properly and I need to have it blocked up before I get under it.

    Is there a way that I am supposed to get the flywheel off? Looks like I have to find a big puller that spans the ~10" across the entire casting. I'm not seeing any nice threaded holes like some things.

    Same thing with the bottom PTO clutch: I got the bolt out of the bottom of the crankshaft but am not seeing a simple way to grab on with a standard puller. Is there a special puller that I am supposed to use or should it just fall off?

    I am looking at replacing the entire engine with a FH641V-AS52, 21 HP, if that is the right one. Looks like ~$1500. I have to get the bottom clutch off first to see what the diameter of my shaft is. I even see a FH721V that says it is 25 HP, an extra $300. I don't know if 6 extra HP is worth the extra $$.

    Suggestions? Ideas? WildAzzGuesses?
     
  4. beebop

    beebop LawnSite Member
    Posts: 20

    the 601v is very easy to rebuild. just did my first, and have put about 50 hours since. can find all of your parts on partstree or cte small engine repair parts websites. cost me about 300.00 for parts using old crank (polished) and original block (cleaned and honed lightly). to get the flywheel off, i screwed the crank bolt back in most of the way,and hit it with a 2 ib. sledge while prying up on the flywheel carefully, don't mean hit it hard, just a good solid tap. as far as the clutch, kept prying and tapping around the pulley on top and it FINALLY started coming down. know these are not the correct way, but they worked for me. if you need another block, saw one on e-bay for around 150.00. best of luck.
     
  5. pjm123a

    pjm123a LawnSite Member
    from FL
    Posts: 141

    I have had good luck with a 2 jaw puller on the flywheel and a 3 jaw puller on the clutch and the pulley on the engine drive shaft that is above the clutch. Some amount of judicious tapping is required as well as patience. The parts must come down evenly. If something gets cocked it will hang. You need to be prepared to tap things back up to even them out. Remember, tapping - not banging or you will bend or break something. When I re-assembled things I used anti-sieze lubricant on some of the parts. Look at the "save the scag" thread. It may help you out since in that thread a 6h01v was moved from one tiger cub to another. There is a picture in there of the pulley above the clutch with a puller on it. I tried to include the picture here but lawnsite will not allow me to upload the same picture twice.
     
  6. Sharpcut 1

    Sharpcut 1 LawnSite Senior Member
    Posts: 450

    He's gonna need a new block because his top bushing is worn to the point flywheel hits coils. Or search on here for the bushing replacement thread, will tell you how to do it. If you ever ran these older FH series engine low on oil, that did'nt have the oil passage at the top of the crank, they will wipe out the top bushing.
     
  7. Roger

    Roger LawnSite Fanatic
    Posts: 5,917

    Maybe the experiences in this thread will be helpful,

    http://www.lawnsite.com/showthread.php?t=406889

    The symptoms sound exactly the same.

    I inquired about a new engine, and was told "not possible." A rebuild is done through a short-block, which is easily available.

    See my experiences in getting off the flywheel. No puller, ... beebop described the procedure exactly.
     
  8. poohboy

    poohboy LawnSite Member
    from MT
    Posts: 14

    I ended up getting a NEW engine:

    I had the bolt out of the crank to get the clutch off the bottom of the old engine.
    I tapped on the edge of the clutch a little bit and pulled on it but it didn't come off easy.
    I found a thin crowbar that had the right bend on it. One little barely pry and the clutch came right off after that first movement.
    I ended up, finally, borrowrenting the right size puller from O’Reilly’s to get the hydraulic drive pulley off.
    The pulley was not real tight on the shaft but it was a pull the whole way to get it to come off.
    Verified that I had the 1-1/8” shaft.

    Ordered from: http://www.engine4less.com/shop/21....x-about-3-15-16-length-crankshaft-engine.html
    THEY didn’t have a new FH601V like what was in it. That was a 19 HP model.
    I got a FH641V that is a 21 HP model.
    They said it should just bolt right on. It was mostly a direct replacement.
    The new one comes pretty much ready to run, just add oil and go.

    The starter that came on the new engine is different, I just used the old starter.
    The new starter looks like it is supposed to have an external electrical solenoid - only one big electrical connector on it.
    I had to change to my old electrical connections harness but that was easy because it just plugs in.
    The new engine only had a threaded plug in the oil drain. My old one had the valve and drain tube. That was easy enough to swap.
    The throttle and choke cable connections were the same as the old one.

    I wanted to run it a while before I updated this in case it didn't charge the battery or I found some other problem.
    So far, no problems.
    The old engine had ~2000 hours on it.
    The new engine starts easier, runs smoother, has noticeable more power, probably a combination of NEW engine and more HP.

    I'm happy to have my mower back. :dancing:
     
  9. Roger

    Roger LawnSite Fanatic
    Posts: 5,917

    poohboy, ... you didn't say anything about the exhaust/muffler connection. Was this simple? Was the old one difficult to get off?
     
  10. larryinalabama

    larryinalabama LawnSite Fanatic
    Posts: 16,464

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