The Green Industry's Resource Center

Thread Tools   Display Modes
Old 05-30-2015, 12:17 AM
pjm123a pjm123a is online now
LawnSite Member
Join Date: Jul 2008
Location: FL
Posts: 136
I have a different model Kawi engine (FH601V) on a Scag Zero Turn Mower. I had what seems to be the same problem you are having. Tried different things to fix it and was able to make improvements using some of the things that have already been suggested in this thread. In the end replacing the coils was what fixed it for me. It still starts and runs great hot or cold. You can read about it here:

Good luck and I hope this helps you out.
I am not a mechanic (except on weekends in my backyard on my own equipment usually with a cold one).
Reply With Quote
Old 05-30-2015, 02:58 AM
herler herler is offline
LawnSite Fanatic
Join Date: Apr 2012
Posts: 5,145
Originally Posted by View Post
Choke is closing fully. No corrosion in boots. Got it to run last night after a lot of cranking. Ran it 5 minutes shut it off. Would NOT start back up
Posted via Mobile Device
Spark plug gap gone wide.
What you describe is a typical symptom of spark plug gap erosion.

Over time spark plug gaps erode, causing the gap to grow wider, usually the process takes some years but the time limit is real.
For example in a car, I believe the erosion is .005" per every 10,000 miles or so.
Every time a spark plug fires, a teenie bit equivalent to some millionths of an inch of steel disappear from the electrode forever.
Thus over millions of crankshaft revolutions, the gap slowly but continually grows wider.

It is quite easy for spark plugs that were set to .030 to grow to .035 and later to .040...
Usually "hard" starts begin around .045"

When's the last time you checked the gaps?
Anytime a plug is pulled, the gap needs to be checked.
They should be set to .030 (thou setting them to .025 extends the re-gapping service interval).

Last edited by herler; 05-30-2015 at 03:04 AM.
Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Layout Style:

Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.
Copyright ©1998 - 2012, LawnSite.comô - Grand View Media
All times are GMT -4. The time now is 03:53 PM.

Page generated in 0.05221 seconds with 10 queries