demolition_man

My starter motor on my zetec mk3 fiesta seized this morning so it was spinning but not engaging the flywheel.

I swapped the starter for a spare i had in the shed but the wiring contacts on the starter motor were in slightly differerent positions as the one i took off was an aftermarket replacement.

I then wired up the replacement motor and turned the key and got....absolutely nothing. The solenoid was not popping and the motor was not spinning, nothing.

I guess i've wired it up wrong... here is a diagram of how it is wired up now:



I've checked all fuses in the fuse box and they are fine?

Many thanks

demolition_man

could it be that i've knackered the ignition switch relay as i forgot to disconnect the battery and sparked my spanner off the old starter when i was removing it?

Chopshop85

iTrader: (4)

I'm not to sure about wiring etc.
If I ever have a problem with a starter motor not engaging I give it a good tw*t with a hammer. Could try this with the old one if that was spinning?
You never know, the spare one might just be dead?

other thing you could do is get the starter and link it straight to the battery to see if it spins up. then you'll be narrowing down issues.

demolition_man

yeah, the one i took off was releasing when i hit it with a hammer, but then it just seized again straight away so i decided to swap it.

Unfortunately, i didn't hook it up to the battery to test it as I was in a hurry to get to work, wish i had now. I've got another one in the shed which is new so i'll bang that one on tonight.

I was just hoping someone could confirm whether the above wiring is correct before i pull it to bits again.

Thanks a lot mate

tabetha

The wiring you show is fine, having caused a spark I would have a look at the fuses, as you may have popped a fuse, usually on pre engaged starters such as yours the solenoid is arranged so that the lower 13mm connection is a little bit of braided wire that goes into the starter motor body, the other 13mm nut then holds the battery and alt wires, with the 1 remianing being direct from the ignition switch, they don't usually use a relay on the solenoid side of the sw, but I can't say for def on yours, just that they don't normally, normally a black/blue wire.
tabetha

demolition_man

i see, thank you for clearing that up i'll whip it off and use the other one then.

thanks a lot

tabetha

No probs hope you get it sorted, can't gauarantee it is a black/blue wire so might need to probe the switch to see.
tabetha

demolition_man

hello mate,

just done battle with it again, and it's won, again. I pulled the motor off and tested it, it turns out that it spins up when i bridge the power over the main threaded terminal and a small spade connector, rather than the smaller threaded terminal as I drew in the diagram above.

So on the floor next to the car i can get the starter working, but then i shoved it onto the engine and turned the key and there was nothing.

To fill me in on a bit of the theory behind it, is the ignition switch providing a live or an earth? It certainly seems that in order for it to work as i have it set up now the ignition switch will need to be live to make the motor work.

If that is live, i think i'll have to start playing with the voltmeter thing, although i've never really understood it :S

botters

iTrader: (2)

quite common on fiestas and escorts to have dodgy wiring connections on the starter and once disturbed start to cause problems! peel a bit of insulation back off the main starter wire (the thick one) and see what the wire looks like, these can go very brittle and give conductivity problems if that is ok get hold of a test lamp (one of those probes that you earth to battery and they light up when the other end is pressed to live) and hold it on the small exciter wire while someone attempts to start if it does not light the test lamp then there is a problem on that wire

tabetha

The ignition switch switches a LIVE current down to the starter solenoid, the small terminal, they will nearly always work without load, but not on load when duff.
The solenoid could be sticking, esp if it is a BOSCH starter ?, connect the leads as said, then take a wire from the main battery connection to the small terminalk that comes from your ignition switch, and switch it manually, NB make sure car is in neutral, before trying!!, leave the ignition key on so lights are lit up(position 2) the engine should start, if it is a solenoid problem you will not hear a LOUD distinctive CLUNK as the ring gear isa engaged by the drive pinion on the starter.
Have found a few here the solenoid connector has been bodged, these need to be 100% perfect, ie a crimped on terminal will not cut it, needs soldering and heat shrinking, recently done a escort diesel with this very problem, new starter new battery new alternator, and it was the solenoid connection, snipped old one off soldered new one on(with adhesive lined heatshrink) and 100% perfect in the cold winter snow we had, even after leaving 2 weeks.
The problem particularly with bosch is the solenoid internals are coated with varnish, fine when brand new but a few years old and the varnish comes off and jams up the solenoid travel, so it can't travel full length, the first part of travel is to engage the pinion(gear) then the next bit is to actually bridge the terminals(inside solenoid) to apply power to the starter so it turns the engaged engine.
tabetha

demolition_man

bloofy hell, you know ur stuff, i'll do some more testing tonight and solder the connector on as i have just crimped on a spade connector for the ignition :P typical.

really appreciate the help