As Doc tried to convey, the problem with most non-mower keyswitches is that they provide a 12 volt+ signal on the ignition wire when the switch is turned on. Putting 12 volts+ on the coil wire will likely cook the coil (I've done that).
What the mower engine needs if for the coil wire to be open (nothing + or -) while it is running. To stop the engine, this wire needs to go to ground.
I drew up a schematic for you, based on what you previously posted. This drawing shows a relay switching the polarity of the ignition to use as a kill switch, like most mower engines use. Please fully test the keyswitch pins' functions prior to using this diagram, as it assumes the functions of the pins as you drew them.
redlinemotorsportts Moderator
2500+ Posts
2500+ Posts!
2014 Build-Off Entrant
2014 Build-Off Entrant
Age : 27 Join date : 2013-03-18 Points : 7245 Posts : 3131 Location : raleigh nc
Well, I dug up the ignition switch in question, and there's simply no discernible part number on it. Sorry.
Thank you for looking its a shame it didnt have any marks as this is a simple route . I see The Rainbow boxer has given a relay way of using my purchased switch to drive the coil to ground . That is a brilliant sketch thank you so much for the time and effort you spent drawing it :-) I think the new switch will have differant modern positions . What I gave you was from the old ignition switch . Do you have a diagram to represent the switch internals so that I can use a meter to get the same pins when my switch arrives please.
I am thinking from what has been said
M -> GND on B ->S starter cranked released B->A
Is this correct?
TheRainbowBoxer Moderator
1000+ Posts
1000+ Posts!
Age : 49 Join date : 2012-04-23 Points : 5461 Posts : 1089 Location : Galion, OH
Not sure how I'd diagram that, but I can go over the specific tests. These tests would be done with no connections made, and using a multimeter on "ohms" or other continuity setting. "should read open" for this example means no connection to 12 volt+ pin or Ground pin/switch case (on "ohms" meter will rest as if not touching anything)
With key in off position: Accessory pin should read open Starter pin should read open Ignition pin should read open for "modern" ignition switch. (should connect to ground pin (and/or switch casing) on standard mower switch)
With key in on position: Accessory pin should connect to 12 volt+ pin Starter pin should read open Ignition pin should read connect to 12 volt+ pin on "modern" switch. (or read open on standard mower switch)
With Key in start position: Accessory pin will show open, or possibly connection to 12 volt+ pin. Starter pin will show connection to 12 volt+ pin. Ignition pin should read open on standard mower switch, or 12 volt+ pin on "modern" switch.
Its possible that the switch will not have a separate accessory pin or a ground pin.
Proud member of the Mower Cycle Gang... aka the "Mowrons!"
My build (Chaos is one of 3 built like this) Chaos Build
Thank you . You are correct the switch I have ordered is a 4 Position (Park/Off/On/Ignition). I presume this means it will not work either as I need an accessory feed as my existing switch has one?
No, you should still be ok... the accessory items in this case (assuming a 12 volt+ ignition) would just tie into ignition, rather than have their own pin.
Edited to add: Not sure what the "Park" position would be used for or how it would work
Proud member of the Mower Cycle Gang... aka the "Mowrons!"
My build (Chaos is one of 3 built like this) Chaos Build
No, you should still be ok... the accessory items in this case (assuming a 12 volt+ ignition) would just tie into ignition, rather than have their own pin.
Edited to add: Not sure what the "Park" position would be used for or how it would work
Presumably could be tied to lights to flatten battery :-p
As Doc tried to convey, the problem with most non-mower keyswitches is that they provide a 12 volt+ signal on the ignition wire when the switch is turned on. Putting 12 volts+ on the coil wire will likely cook the coil (I've done that).
What the mower engine needs if for the coil wire to be open (nothing + or -) while it is running. To stop the engine, this wire needs to go to ground.
I drew up a schematic for you, based on what you previously posted. This drawing shows a relay switching the polarity of the ignition to use as a kill switch, like most mower engines use. Please fully test the keyswitch pins' functions prior to using this diagram, as it assumes the functions of the pins as you drew them.
Hi I have received my relay and wonder if your diagram is wrong you quote use of 87a which i think should be 87. Further I am curious about the earths can these be connected together and wired to the earth that comes to the switch please? Is NC 87a earth supposed to be floating and not connected to anything?
I have made up switch like this:
Doc Sprocket Site VIP
2500+ Posts
2500+ Posts!
2018 Build-Off Entrant
2018 Build-Off Entrant
2021 Winner of Winners
2021 Winner of Winners
1st Place Build-Off 2016
1st Place Build-Off Winner 2016
Age : 50 Join date : 2013-04-21 Points : 7080 Posts : 2914 Location : Ontario Canada
As I understand it, the whole point of using 87A is that it (earths) grounds when the trigger coil is de-energized with the switch in the OFF position- thus completing the path from the engine's kill wire (terminal 30) to ground (earth). Remember that the engine's kill circuit must be "closed" (completed, continous to earth) to shut down. Hence the need for the relay in the 1st place to use the "incompatible" key switch.
All Earths may be interconnected.
Please note that in order for the system to work, 12v must be maintained at the relay or the engine will not run. Ensure the relay is powered up before attempting to start. If, for example- you were to try and jump start engine by applying 12v+ directly to the starter terminal, engine will crank over but not fire unless you feed the relay coil 12v at the same time.
As I understand it, the whole point of using 87A is that it (earths) grounds when the trigger coil is de-energized with the switch in the OFF position- thus completing the path from the engine's kill wire (terminal 30) to ground (earth). Remember that the engine's kill circuit must be "closed" (completed, continous to earth) to shut down. Hence the need for the relay in the 1st place to use the "incompatible" key switch.
All Earths may be interconnected.
Please note that in order for the system to work, 12v must be maintained at the relay or the engine will not run. Ensure the relay is powered up before attempting to start. If, for example- you were to try and jump start engine by applying 12v+ directly to the starter terminal, engine will crank over but not fire unless you feed the relay coil 12v at the same time.
I see a switch with a light in your future LOL, Also so you don't kill the batt when giving the relay 12v all the time.
Doc Sprocket Site VIP
2500+ Posts
2500+ Posts!
2018 Build-Off Entrant
2018 Build-Off Entrant
2021 Winner of Winners
2021 Winner of Winners
1st Place Build-Off 2016
1st Place Build-Off Winner 2016
Age : 50 Join date : 2013-04-21 Points : 7080 Posts : 2914 Location : Ontario Canada
As I understand it, the whole point of using 87A is that it (earths) grounds when the trigger coil is de-energized with the switch in the OFF position- thus completing the path from the engine's kill wire (terminal 30) to ground (earth). Remember that the engine's kill circuit must be "closed" (completed, continous to earth) to shut down. Hence the need for the relay in the 1st place to use the "incompatible" key switch.
All Earths may be interconnected.
Please note that in order for the system to work, 12v must be maintained at the relay or the engine will not run. Ensure the relay is powered up before attempting to start. If, for example- you were to try and jump start engine by applying 12v+ directly to the starter terminal, engine will crank over but not fire unless you feed the relay coil 12v at the same time.
Ok Here we go made up switch unit just need to plug it in and try it will let you know if it starts before cutting in 19mm hole into dash
TheRainbowBoxer Moderator
1000+ Posts
1000+ Posts!
Age : 49 Join date : 2012-04-23 Points : 5461 Posts : 1089 Location : Galion, OH
Doc is correct. The point of using 87A is so that the connection only happens when the power to the relay is off.
The relay works like this:
When coil is not energized 30 (which in the schematic is connected to ground) will be connected to 87A 87 will be open This causes the coil to ground out and the engine to shut down
When coil is energized 30 (which in the schematic is connected to ground) will be connected to 87 87A will be open This stops the coil from being grounded and allows the engine to run
Proud member of the Mower Cycle Gang... aka the "Mowrons!"
My build (Chaos is one of 3 built like this) Chaos Build
When coil is energized 30 (which in the schematic is connected to ground) will be connected to 87 87A will be open This stops the coil from being grounded and allows the engine to run
I think you mean 87 here not 87A.
I have connected with the following wiring B red red two wires BAT on new switch S red yellow stripe STR on new switch M red silver stripe. RELAY 86 G Black to RELAY 87A, 85 A red black stripe ACC on new switch RELAY 30 Common to coil on engine
I am not sure A red black stripe should go on ACC on new switch this is the park position for the switch G think it should go on IGN?
Last edited by FOSWMT on September 23rd 2013, 3:15 pm; edited 1 time in total
Doc Sprocket Site VIP
2500+ Posts
2500+ Posts!
2018 Build-Off Entrant
2018 Build-Off Entrant
2021 Winner of Winners
2021 Winner of Winners
1st Place Build-Off 2016
1st Place Build-Off Winner 2016
Age : 50 Join date : 2013-04-21 Points : 7080 Posts : 2914 Location : Ontario Canada
No- Stick to what TRB said. You NEED it that way. engine kill circuit must NOT be completed to earth in order for the engine to run. When circuit is complete to earth, engine will NOT run.
No- Stick to what TRB said. You NEED it that way. engine kill circuit must NOT be completed to earth in order for the engine to run. When circuit is complete to earth, engine will NOT run.
87 is not connected 87A is connected to earth as was taken from diagram above?
Doc Sprocket Site VIP
2500+ Posts
2500+ Posts!
2018 Build-Off Entrant
2018 Build-Off Entrant
2021 Winner of Winners
2021 Winner of Winners
1st Place Build-Off 2016
1st Place Build-Off Winner 2016
Age : 50 Join date : 2013-04-21 Points : 7080 Posts : 2914 Location : Ontario Canada
Correct. Instead of getting lost in potentially confusing verbal descriptions, simply wire the relay according to the schematic TRB drew up. While the actual "Drawing" of the relay could be a bit misleading, the termination numbers ARE correct. Ignore terminal 87, it's not being used here. 85 and 86 are the trigger coil in the relay, 30 and 87A are what complete the engine's KILL circuit to turn the engine OFF.
My Ignition switch didnt work . I took all the wires of the switch iyt still ran I connected all of the wires together it still ran has someone bypassed the switch
Gazelle actual Wiring Diagram the other one was wrong page 1 sorry google found it
From this the wiring colors would be different as would the switch poles: L Two red wires M Ignition switch light Red yellow stripe B Battery Red with black stripe S Starter Red with Silver stripe GND Black
The diagram just says Engine Cut off for this but the switch in the off position seems to be connected to M ignition switch.
Switch connections ign pos 1 -> B connects to L, Gnd Not connected to M goes to outside of switch. ign starter ->> S connects to Battery, B connects to L, Gnd Not connected to M goes to outside of switch.
I think therefore 87 should be M 87a should be earth on tractor 30 should be G 85 should be ground tractor
On new switch BAT should be B IGN should be 86 and L ST should be S
Can anyone help please?
Last edited by FOSWMT on September 25th 2013, 10:17 am; edited 1 time in total
Had one amber light no start but could not see to do much. Had pulled red ignition contacts off so need to check those tomorrow are on properly. Also could not see if I had petrol Starter clicked but no spin of starter was detected but that could be an earth issue as all tin ware was painted.