Kawi FH721V carb questions and hard start

Discussion in 'Mechanic and Repair' started by Lightningtruck, May 16, 2008.

  1. Lightningtruck

    Lightningtruck LawnSite Member
    Messages: 3

    Have a 2005 Super Z Hustler with a 25hp Kawi (FH721V) that I am having some hard starting issues with. Hot or cold. Has 850 hours on it. Did a search of the forum here and got a lot of great info on things to check, which I am looking into. But right now I am planning to rebuild the carb this weekend, and have a quick question on that.

    On the carburetor, under the two welch plugs (part number 92066-7009), there are what appears in the parts diagrams to be needles (says Needle, Jet, part number 16187-7002 in the diagram I found on the 'net). I didn't pop the plugs and see what the needle materials are, but can I assume that they are metal and not something rubber or plastic? Reason I ask is because I want to disassemble and put the carb in that strong carb dip solvent, and that solvent will destroy anything plastic or rubber. Don't want to mess anything up that I can't see. Just curious if you veterans might know the answer to this without me having to open 'em up.

    The other thing on the carb is that the previous owner screwed up the little clips that hook the choke and throttle rods up to the throttle and choke shafts. According to what I can find in the parts books, it looks like those stupid clips only come with the shafts, which are about 28 bucks each. Any of you guys have any insight on where or if I can get just those clips?

    Besides the carb rebuild, the other things I will look at are:
    - Choke linkage: I made sure and pushed the choke full closed by hand (via the shaft) and it didn't help.
    - New battery. Measures 11.3V while cranking.
    - Fuel solenoid clicks when turning the key to "on"
    - Did find that the valve lash was loose....intake was on the order of .006" if I recall correctly. Will lash the valves tomorrow to 003 intake and .005 exhaust.
    - Haven't unhooked the B terminal from the switch to eliminate all the safety switches from the system yet. Need to try that tomorrow.
    - Will measure the coils (Ohm check in the manual) to make sure we got good jparts.
    - Am putting a new fuel filter on tomorrow, just for fun. I don't think this is the culprit, but they are cheap enough so why not.

    Any other thoughts on what I should check?

  2. thezaz

    thezaz LawnSite Member
    Messages: 58

    is the fly wheel contacts rusty what can make it do that. the magnet that is ?
  3. Lightningtruck

    Lightningtruck LawnSite Member
    Messages: 3

    Hmmm, I didn't pay attention to that, but I will check in the morning. They will be shined up in a hurry. :) Thanks for the tip.

  4. Tharrell

    Tharrell LawnSite Silver Member
    Messages: 2,967

    I know it sounds a little silly but, check the brushes in your starter. Do a search on my name and you'll see what I went through. Had the bottom replaced for about $24 and it cranks like a new engine. I thought it was a carb issue also. Tony
    Mine is a 601v
  5. Lightningtruck

    Lightningtruck LawnSite Member
    Messages: 3

    Well, it lives today, and starts with a quick twist of the key and purrs like a kitten!

    Ended up stripping and dipping the carb, installed all new seals and all inside. Re-made the clips/rivets for the linkage so those are perfect now, and got the choke shutting tight. Fuel solenoid checked out good. Good battery voltage while cranking (but will remember that tip on the starter.....I also have a Lesco Z2 with a slow cranking FH721 that probably needs this). But the big thing was, get this, the valve lash on both intakes was at .017, and the exhaust was .024!!! So now they are .003 and .005, respectively. Coils measured out good. Ended up shining up the magnets on the flywheel, and set the air gap on the coils to .010". One of them was really out to lunch. Didn't do a fuel filter yet because I fogot to buy one at the parts store this morning.

    Bottom line is that I'm happy as a pig in slop. Starts and runs NICE now. Amazing what a bit of a tune up will do.

    Now I have to go get my Lesco Z2 with the same engine starting better. But it cranks super slow (but with 11.0V battery during cranking), so I'll start with the starter. And all the other items on the list. Shouldn't be any reason it doesn't run like the one I did today.

    Thanks again for the help, even if it was not today, it was through the forum archives. The search function works!



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