QuestionQUESTION: I started the '96 all-wheel-steer John Deere 425, put the throttle up to full, lifted the dash-mounted PTO switch up and immediately, the engine killed. I tried to restart the engine-- it cranked as normal, but would not fire. I checked for spark with an inductive type tester. It showed no spark when the engine was cranked. This has been an intermitent problem for about a year, but this time it's permanent.
One other clue: when the engine started to die, I quickly shut the PTO switch back off. The engine continued to wind down. (I thought if there was problem with the dash mounted PTO switch, the engine had plenty of time to recover and come back on.)
Appreciate any help you can give. THANKS!
Roger
ANSWER: Hello Roger:
From your Description it Sounds like the Seat Safety Switch is Bad. When the PTO was Engaged, the Safety System Shut Off the Engine because the Seat Switch was Not Engaged and the Safety System Grounded the Ign Coil/Igniter and Stopped the Spark Plug/s from Firing. The Following is an Instruction File for the Safety Switch System. Any Input is Appreciated. The Color Code of the Wires May be Different than those I Use as a Reference in the Instruction File. **PLEASE REMEMBER THAT THE INSTRUCTIONS FOR CHECKING THE SAFETY SWITCHES IS JUST THAT!!! FOR CHECKING ONLY. I NEVER Suggest a Mower be Operated with a Safety Device or Switch Disconnected or Bypassed. Now. On Some Model Mowers you can Simply Unplug the Safety Switch from the Harness. On Other Models you have to Place a Jumper Wire Between the Harness Terminals (on the 4 Post Switch (Clutch/Brake) Jumper from Same Color Wire white to White First and then Check for Fire, Now Include the Black to Black Wires if No Fire. Check the Clutch/Brake and the Blade/PTO Safety Switches First. Check the Seat Safety Last. Usually the Seat Safety is Not in the System for Starting the Engine. Just to Ensure Someone is in the Seat when Engaging the Transaxle and/or Blades. Use a Paper Clip or a Short Wire to Make a Jumper.** If you Hit a Snag or this Does Not Correct the Problem, I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.
Good Luck
Respectfully
John
PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Comments and Ratings are Greatly Appreciated. Thanks.
Respectfully
John
---------- FOLLOW-UP ----------
QUESTION: John-
Not going well. Replaced the seat safety switch. No change. Dealer thought it was the "time delay module"? He replaced that. No change. He put on a new "ignitor". No change. Now he thinks it is the circuit board, which he will try today. Really frustrated, and I'm guessing my bill will be more than a new lawn tractor. Any ideas based on all this?
Thank you,
Roger
AnswerHello Again Roger:
There is a Pulsing Coil that is Usually the Cause of No Fire to the Plugs on this Model and it should have been Changed Before the Ignitor. Pulsing Coils on this Model seem to Go Bad about 3 to 1 of the Ignitors. Did they Test the Brake Switch? Depending on the Safety System Design, the Brake Switch will Stop the Plugs from Firing also. Please, Do Not Hesitate, If you Hit a Snag or this Does Not Correct the Problem, I am Here if You Require More Assistance. Hope this Helps. Let me Know What Happens, Please. May the All Mighty Bless You and Yours. Thanks.
Good Luck
Respectfully
John
PS: I am Allowed to Answer 10 Questions a Day. If you See I am Maxxed Out, then Try Submitting your Question at or Just After 8pm EST (US). My New Day Starts then. Comments and Ratings are Greatly Appreciated. Thanks.
Respectfully
John
