no spark on 631

Larharm · Regular Joined: 07 Nov 2011 Posts: 80 Report to Moderator

purchased new switch it has two lead wires both connect to terminal block one on each side of block.
there is no connection on switch to run wire direct from switch to coil like it said on early post Ford dealer faxed me a electrical diagram and it shows a relay with 2big post and 1 small. then i went there and bought a relay they sold me one with 2big post and 2small like the parts book shows anyway still no spark to coil

old · Posted: Wed Oct 10, 2012 7:00 am Post subject: Re: no spark on 631

Sounds like you got it wired wrong still. If you can run a hot wire from the battery to the ignition side of the coil and it runs then you know your wiring is wrong. To be wired right you should have the one side of the ignition switch hooked to the map gauge and the other wire going straight to the coil

Larharm · Regular Joined: 07 Nov 2011 Posts: 80 Report to Moderator

will the coil take a direct 6v hook up for test from battery without damage

awhtx · Posted: Wed Oct 10, 2012 7:46 am Post subject: Re: no spark on 631

The 4 post relay is correct for a 631.
One big post to battery, other to the starter. It doesn't matter which one goes where.
One small post to the starter button on trans, other to the switched side of the terminal block. It doesn't matter which goes where.
One side of terminal block- wire from key switch and wire from battery.
Other side of terminal block (the switched side)- other wire from key switch, wire to small post on starter relay and wire to coil. When the key is turned ON you have power to the starter relay and power to the coil.

Larharm · Regular Joined: 07 Nov 2011 Posts: 80 Report to Moderator

it is and was wired the way you mentioned i am not trying to rewire just trying to find out why no spark it run okay before the way it is wired. i will replace the relay and see if that does it

old · Posted: Wed Oct 10, 2012 8:18 am Post subject: Re: no spark on 631

YES a 631 uses a round can coil and they are made to handle the full 6 volts of the system. Your tractor is not the old front mount weak square coil that burns out easy. As a matter of fact a round can 6 volt coil will handle 12 volts for a good long time as long as the switch never gets left on with out the engine running so YES you can safely hot wire it

awhtx · Posted: Wed Oct 10, 2012 8:24 am Post subject: Re: no spark on 631

The starter relay has nothing to do with spark.
With the key ON do you have power to the coil?

Larharm · Regular Joined: 07 Nov 2011 Posts: 80 Report to Moderator

found a bad wire to coil so now have spark

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