Starter button

[Badger]

Whilst working on the wiring loom on the Landy, i think i found out a way to install a starter button due to a balls up on my behalf.

I couldn't for the life of me work out why the Landy wouldn't start after pulling cables away from the steering column, and after a fair few hours i found it was the red/white cable which plugs into the back of the ignition barrel & starter relay had popped off.

Anyway to get around it i fed a cable from a live to the relay ( red/white cable ) and this caused the engine to fire when the ignition was on.

So is it correct to run a live into a starter button, then onto the red/white input ( from starter motor? ) to the relay? This works by using just a cable, so i assume it'll work with a push button ??

The ignition has to be on for this to work, i tried it with the key out and it didn't work.

Ta

 

[Station House]

Can't think of a reason why it wouldn't work Paul - as you as long as the ignition is already on

All that 'final turn' of the key does is makes the circuit, so a push button would do the same

 

[Badger]

Good to hear SH

 

[bluehaze]

Paul,

Do you need to consider the rating of the switch?

 

[jai_landrover]

The red white wire is pretty beefy would have a complete gusetimate of around 40A but thats just a guesstimate. I need to do the exact same thing on my offroader next weekend most of the starters are rated at 20a but some with a bigger switch behind it are 30a but I'm stil not sure thats enough. I'd rarther go bigger and make sure it doesn't burn out cos at a comp that would be a ****er!!

 

[jai_landrover]

I know spyderman had a cheapy push button switch and it burnt out that was 20a I think he fitted a metal housing 30a one but mine needs to be semi water proof having no roof sides whatsoever.

 

[The Mad Hat Man]

I know it is stating the obvious, but it depends on the current going through it .

if it is directly connected to the starter motor, it will need to be a lot bigger than thru a relay.

 

[jai_landrover]

Lol cheer MHM I'm sure i was taught that somwhere with electronics lol. hehe. Must get my ammerter out scrap that must get my Big ammeter out!!

 

[jai_landrover]

Most I have seen are direct to the starter solonoid which is a bit mad really considering the possible current draw. Obviously its not as big as the main starter motor draw 100's of Amps

I guess it an argument for the later smaller starter motors on the RRC less current draw needed to throw the starter in and alot less current draw when starting

 

[jai_landrover]

These most definatly burn out direct to the starter solonoid Ask (Spyderman)
Quality Waterproof, Starter, Push Button Switch (722) | eBay

These look better quality but without measuring the current draw were all ****ing in the wind without a wind sock!
Push Button Starter Switch 30amp RACE RALLY KIT CAR 12V | eBay

 

[The Mad Hat Man]

Starter motor solenoids take (typically) 35 amps to engage the solenoid and then the holding current drops to about 10 amps. I would advise wiring the starter button to a 45Amp relay.

 

[jai_landrover]

Yup I'm about to get a 70A jobbie need it to be reliable ane I like the ring terminals

 

[jamesmartin]

op is using vehicle relay so doesnt need anything special

 

[jai_landrover]

Well My 90 hasn't got a relay the ignition is the switch

 

[jai_landrover]

Right I may well be talking crap I remember maybe wrongly that my switch has a seriously hd red white wire on the back of the switch same dia as the cable to the soloid maybe I missed the solonoid in the dash will have a look see tomorrow.

 

[jai_landrover]

Workshop manual for a 1993 def shows a relay so should be there somwhere.

 

[jamesmartin]

depends on age ,some ealier go direct like series ,some go from switch to relay ,op mentioned his went to starter relay,

 

[jai_landrover]

Think mine is the earlier type. Well spotted JM I was overthinking (more about my trialer tbh)

 

[The Mad Hat Man]

A starter motor from a normal 2 Litre petrol car draws between 60 and 200 Amps when turning over the engine when the oil is warm and thin.

Under winter conditions, this current can easily double when the oil is thick.

Diesel engines have a very high compression ratio e.g. 22:1 and require more powerfull starter motors. On average they draw between 300 and 500 Amps for average sized car engines 2 to 3 litre while on truck engines the current could easily reach 1000 Amps at initial turn over.

 

[jai_landrover]

Well OP if you go to your relay then a 20a or 30a jobbie will work for you.


Sorry to hijak for a wee sec but anyone know where I can get Cheaply bowden cables about 1.5 meters long?? ideally with a t handle?