electronic ignition question on 620lp

rick deere

Well-known Member
Never had this set up before just bought this tractor and not getting spark to plugs is there anything I can do or to ck to find problem? will test light help any?? thank you.
 
Don't know will use test light and ck it tomorrow, my email is open Ill see how it goes. do you have a contact number, Jf I do what next.
 
(quoted from post at 20:23:55 11/19/17) Don't know will use test light and ck it tomorrow, my email is open Ill see how it goes. do you have a contact number, Jf I do what next.

Email me at [email protected] if ya want. But I'd check to make sure first your getting power to coil.
 
Rick, you ask "will test light help any??"

IT SURE WILL

If you have a 6/12 volt DC test light, put the alligator clip ground clamp to a good clean metal part of the frame ground and the sharp tip probe end to the input (NOT to distributor but the one from the ignition switch) side of the coil. Turn the ignition switch on and see if the light glows indicating voltage is at least getting to the coil via an turned on ignition
switch.

There are other ways to test with your vision alone if you dont have a test light.

You also need to see if the coil itself is producing a HV spark independent of any cap or rotor or plugs or plug wire problems SEE MY TROUBLESHOOTING PROCEDURE TO DESCRIBE HOW TO TEST THE COIL orrrrrrrrrrrr see the links James Howell posted about coil testing on You Tube in a post below

While my Ignition Troubleshooting Procedure is designed for regular points ignition, much of it still applies its just that a properly wired and working electronic switch replaces the opening and closing of mechanical points.

THEREFORE if all is working you still have to have voltage on the coils input when the ign is turned on and then on the coils other output to distributor terminal the test light should flash ON and OFF if the engine is rotated slowly.

There's not enough info to say too much more now but my procedure can still help

John T
John Ts Ignition Troubleshooting
 
I know the coil, that's on there has one side grounded to tractor , I've never seen this before.And the distributor has two wires going to it. One from the switch I guess the other from the coil.
 
(quoted from post at 22:39:05 11/19/17) I know the coil, that's on there has one side grounded to tractor , I've never seen this before.And the distributor has two wires going to it. One from the switch I guess the other from the coil.

The coil shouldn't have anything grounded to it. One wire is positive and comes from switch, the other goes into distributor and goes through the ei, then that should be grounded. If you have a wire from your coil going directly ground that's why you have no spark
 
Rick, you're correct when you state "This set up has no points or condenser" The elec switch takes the place of those components. When the ign switch is on it sends 12 volts to the coils input (NOT to dist terminal) and then the elec switch replaces the points and condenser by providing a ground (when conducting) to the coils other output to dist terminal. The coils output to dist is grounded ONLY when the switch is conducting but then the circuit opens and coil current is interrupted and the coils HV tower produces high voltage to fire the plugs.

John T
 
I have printed that off before but I should send a copy to a former co-worker. The one that used my volt meter to test for spark. Grrrrrrrrr
 
Update the tractor was wired correctly the wire on the coil was to be grounded, the man I bought it from had the battery in backwards ive got plenty fire now thank you all.
 
CONGRATULATIONS, Consider yourself LUCKY as often if an electronic switch is wired at the wrong polarity ITS TOAST....The coils output is grounded via the elec switch (replaced mechanical points) as it closes to conduct coil current to ground and then opens when its time for the coil to fire.......

Best wishes, thanks for the feedback

John T
 
yep everyone I ask said the coil should not be grounded but they were wrong so I learned something today and I wont forget it. And you don't get instructions with a tractor you buy from someone else. But it starts and runs very good and I'm a happy camper. Thank you all , and have a great Thanksgiving.
 
Indeed the coil can NOT produce a spark UNTIL its output is first temporarily grounded (via closed points or switch) so it conducts current and stores energy, but then the current needs interrupted by points opening or an elec switch opening at which time ONLY THEN (current flows to ground then it stops) does it produce the high voltage capable of arc jumping current across the spark plug gap.............

Happy Thanksgiving to you also

John T
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top