benbenukuk Posted October 4, 2009 Posted October 4, 2009 Hello, I have a couple of questions about the cut off switch, Can I wire the resistor to the battery earth? Where it says Ignition Coil do I take my fuel pump there? Do I have to put the Ignition switch on the other side or can I leave it out? And do I have to put the main electrical feed on the last remaining spade connection? cheers. Ben Quote
mmgemini Posted October 4, 2009 Posted October 4, 2009 Do a search under FIA battery master switch. I've put the wiring diagram up somewhere. Yes the fuel pump solenoid is the ignition. HTH Quote
LandyManLuke Posted October 4, 2009 Posted October 4, 2009 The resistor needs to be connected to negative earth, the battery would be a better choice than a rusty bit of chassis, assuming you don't isolate its negative terminal. The other side of the '1' pair of contacts can just be daisy chained on to the switched side of the main contacts - it needs to be able to earth the alternator. The '2' pair of contacts should go in series between the stop solenoid and the ignition switch. Quote
benbenukuk Posted October 4, 2009 Author Posted October 4, 2009 Do I have to connect the ignition switch or can I leave it out? Quote
LandyManLuke Posted October 5, 2009 Posted October 5, 2009 I don't know about the MSA rules, but if you're happy wiring glow plugs,fuel solenoid and start relay yourself, then I don't see why not. Normally, fitting an FIA master switch doesn't require re-wiring the ignition switch at all. Likewise, you don't need an FIA master switch to wire your own starting circuits, so the two are quite separate. Quote
benbenukuk Posted October 5, 2009 Author Posted October 5, 2009 Do I need to connect the fuel pump to both the coil side and Ignition switch side? Quote
Orange Posted October 5, 2009 Posted October 5, 2009 Ben, If you are up in the Maidstone/Aylesford area, you can pop in and look at mine if you like... It's on a 300 truck cab 90, so might give you a bit more of a hands-on idea. Drop me a PM to arrange if you like... Cheers Adrian Quote
LandyManLuke Posted October 5, 2009 Posted October 5, 2009 Do I need to connect the fuel pump to both the coil side and Ignition switch side? What are you doing? rewiring 'standard' wiring to just add the kill switch, or starting from scratch? If you're adapting from standard; - cut the fuel solenoid wire - take one of the newly cut wires to one side of the '2' terminals - take the other wire to the other side of the '2' terminals. In practice, I'd run a new wire from the Kill Switch to the solenoid, and extend or replace the original feed. If you're wiring from scratch, you'll have to tell us a bit more about your plans. Quote
white90 Posted October 5, 2009 Posted October 5, 2009 I guess you mean Fuel Injection pump? the stop solenoid needs to be interupted on the switch the other terminals are for the resistor to protect the alternator the large connections for the battery. Quote
p38rr Posted October 5, 2009 Posted October 5, 2009 As i understand it the MSA requirements are that the engins stops when the isolator is turned off. A very easy way to do this is fit a good quality cut off switch and wire the alternator charge to the battery side. This will stop the engine when the switch is turned to the off position and eliminates the need for fancy expensive switches and diodes and all the additional wiring!!. The alternator will not be damaged as the alternator remains live as the charge wire is still connected to the battery positive. Simples!! Quote
white90 Posted October 5, 2009 Posted October 5, 2009 But the correct switch fitted correctly isolates the battery as well as stopping the engine this is far the better idea. and the switch at £15ish is not to Pricey? Quote
p38rr Posted October 6, 2009 Posted October 6, 2009 So does the above, Just means less wiring, no diodes and less to go wrong. Oh, and you can fit a proper isolater, not one of those plastic body ones Quote
LandyManLuke Posted October 6, 2009 Posted October 6, 2009 Your proposed method still involves significant re-wiring, as the alternator output is only taken to the starter motor as standard, and still results in a heavy-current non-isolated wire in the engine bay, which might not be an issue with a diesel, but certainly could be a issue with a petrol engine. It's a resistor, not a diode. fairly significant difference! Quote
ltwt1981 Posted October 7, 2009 Posted October 7, 2009 MSA rules are the isolator should cut all power to the vehicle, it should be on the power side of the battery not the earth. In practice just cut it into the live cable from the battery, alternator should not be damaged unless you switch off when revving, but use a diode system if you feel better about it. It's to prevent fire from earthed lives in the event of an accident. National A scrutineer. Quote
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