Page 1 of 2 12 LastLast
Results 1 to 10 of 17
  1. #1

    Join Date
    Aug 2012
    Posts
    7
    Location
    North Carolina
    Mower
    model 917.258523

    Riding mower wont start. Flywheel turns full turn and stops.

    Ok, I have a craftsman riding mower, model 917.258523. It ran fine a week ago. I had to replace the flywheel because the plastic one that came on the motor started cracking and messing up the starter gear. I replaced the flywheel and now when I turn the key the motor turns over a full turn and then stops. If I hold the key it will continue to make a full turn and stop. the motor pauses for about 5 seconds then rotates again. I can spin the motor both ways by hand fine. I checked the spark plug and there is plenty of spark. I also thought it might have been the battery but used jumper cables and hooked it up to my car and it did the same thing. I checked the key on the crankshaft and it is still entaced. What am I missing or what can I try. Thanks

  2.  

  3. #2

    Join Date
    Aug 2012
    Posts
    822
    Location
    California
    Mower
    TMW REPAIR & THE MUSICIANS WORKSHOP RECORDING STUDIO

    Re: Riding mower wont start. Flywheel turns full turn and stops.

    I am certain that the flywheel is NOT plastic. Perhaps the fan or fins are plastic. If you removed the entire flywheel, did you remember the flywheel key? This is what times the ignition

  4. #3
    pugaltitude's Avatar
    Join Date
    Jan 2012
    Posts
    948
    Location
    Scotland
    Mower
    Lots

    Re: Riding mower wont start. Flywheel turns full turn and stops.

    What engine is fitted?
    Is there any model type or code numbers?
    The "best" engine you will ever own!

    Briggs & Stratton MST.

  5. #4

    Join Date
    Aug 2012
    Posts
    7
    Location
    North Carolina
    Mower
    model 917.258523

    Re: Riding mower wont start. Flywheel turns full turn and stops.

    The key that you are talking about is the one that holds the flywheel assembly to the crankshaft, correct. If this is the one your talking about I did put it in and just checked it to see if it was sheared and it isn't.

  6. #5

    Join Date
    Aug 2012
    Posts
    7
    Location
    North Carolina
    Mower
    model 917.258523

    Re: Riding mower wont start. Flywheel turns full turn and stops.

    The engine model number is 28N707. It is a 15.5hp briggs and stratton

  7. #6
    pugaltitude's Avatar
    Join Date
    Jan 2012
    Posts
    948
    Location
    Scotland
    Mower
    Lots

    Re: Riding mower wont start. Flywheel turns full turn and stops.

    What happens if you take the spark plug out and turn the key to engage starter?
    The "best" engine you will ever own!

    Briggs & Stratton MST.

  8. #7

    Join Date
    Aug 2012
    Posts
    7
    Location
    North Carolina
    Mower
    model 917.258523

    Re: Riding mower wont start. Flywheel turns full turn and stops.

    If I take the spark plug out then the motor spins just fine.

  9. #8
    pugaltitude's Avatar
    Join Date
    Jan 2012
    Posts
    948
    Location
    Scotland
    Mower
    Lots

    Re: Riding mower wont start. Flywheel turns full turn and stops.

    Check your valve clearances.
    Valve Clearance | Briggs & Stratton

    If ok then the decompressor on the camshaft could be broken and not allowing engine to turn past conpression stroke.
    A decompressor lets excess pressure out of engine to allow starting.

    Inlet should be 0.003"-0.005"
    Ex should be 0.005"-0.007".
    The "best" engine you will ever own!

    Briggs & Stratton MST.

  10. #9

    Join Date
    Aug 2012
    Posts
    7
    Location
    North Carolina
    Mower
    model 917.258523

    Re: Riding mower wont start. Flywheel turns full turn and stops.

    I will check the valves. I need to buy a gauge for it. In the mean time. Where is the decompresser and is there any way to test it.

  11. #10
    pugaltitude's Avatar
    Join Date
    Jan 2012
    Posts
    948
    Location
    Scotland
    Mower
    Lots

    Re: Riding mower wont start. Flywheel turns full turn and stops.

    Quote Originally Posted by William2146 View Post
    I will check the valves. I need to buy a gauge for it. In the mean time. Where is the decompresser and is there any way to test it.
    The decomp is on the end of the camshaft which is in the engine.
    The only way to test it is checking valve clearances.
    With the rocker cover off and turning the engine by hand the valves should go up and down.
    Looking closely 1 valve should open then close and then it should open/close ever so slightly like a small bump.
    Thats the decomp working.
    If it doesnt bump then the decomp may be broken and you would need to replace the camshaft.
    Read the attachment i posted about setting valve clearances carefully.
    You only need feeler guage.
    The "best" engine you will ever own!

    Briggs & Stratton MST.

Similar Threads

  1. CubCadet Riding Mower Wont Reach Full Idle
    By JimT in forum Small Engine & Mower Repair
    Replies: 5
    Last Post: 06-22-2012, 10:15 PM
  2. Craftsman riding lawn mower wont start. Drastically need help.
    By CraftsmanProblems in forum Small Engine & Mower Repair
    Replies: 9
    Last Post: 11-21-2011, 01:39 PM
  3. Repairs Riding Mower wont start again
    By red69viper in forum Craftsman Forum
    Replies: 11
    Last Post: 11-15-2011, 03:16 PM
  4. Murray Riding Mower wont start.
    By bjohnson85 in forum Murray Forum
    Replies: 4
    Last Post: 05-12-2011, 03:16 AM
  5. Replies: 15
    Last Post: 04-17-2011, 02:08 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •