445

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Got a 445 John Deere that won't fire right cylinder. Installed new coils from John Deere new caps for sparkplugs new plugs all without making a change . Checked compression , 170 is min. I'm at 198 . Checked valve settings - ok. Checked while running by spraying gas down the throat and the cylinder came alive . Thinking electronic injector could be the problem so changed out throttle body complete with "known to be good" unit as the JD tech manual advises, no change . Was wondering if anyone could tell me if the pulsar coil which signals the injector is sequential alternating left and right signals to injector or it just fires every time the mag comes around on the flywheel ? Anybody got any ideas ? Any help would be appreciated.
 

StarTech

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If the RH spark plug is not firing and LH is firing. First make sure battery voltage is reaching the coil. Now using a test light. Connect one to the positive battery post. Now Right coil should have a Black/Yellow or Blue/Yellow wire. Put the test light other end on it and crank if it is getting its trigger the light should flash. The trigger wire is grounded to fire the ignition coil. If not flashing then the fuel inject module is bad.
 
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Hammermechanicman

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If you google "jd445.pdf" you can download the service manual from garden tractor talk website.
 

Tiger Small Engine

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Got a 445 John Deere that won't fire right cylinder. Installed new coils from John Deere new caps for sparkplugs new plugs all without making a change . Checked compression , 170 is min. I'm at 198 . Checked valve settings - ok. Checked while running by spraying gas down the throat and the cylinder came alive . Thinking electronic injector could be the problem so changed out throttle body complete with "known to be good" unit as the JD tech manual advises, no change . Was wondering if anyone could tell me if the pulsar coil which signals the injector is sequential alternating left and right signals to injector or it just fires every time the mag comes around on the flywheel ? Anybody got any ideas ? Any help would be appreciated.
Pull the kill wires on ignition coil and see if you get spark then.
How do you get a reading of 198 psi on a compression test? How can 170 psi be the minimum compression reading? Seems really high for both readings.
 

StarTech

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These are not magneto type coils They have 12v in and the control module is grounding them via the other terminal to fire the plugs.
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