Lewis badger excavator electrical problem

[Exsquaddie]

Hello all, I have a problem, I turn the ignition key, dash lights up, I turn to start and one big click near the starter motor housing and then nothing, then the ignition wont reset and lights on the dash wont illuminate, UNLESS.... i disconnect the battery and reconnect, this seems to reset the system but again the same thing CLICK!

I bench ran the starter motor (all good), and the battery is good, checked all fuses, Any ideas before I start to strip the beast apart?
Thanks all

 

[V8Druid]

Hello all, I have a problem, I turn the ignition key, dash lights up, I turn to start and one big click near the starter motor housing and then nothing, then the ignition wont reset and lights on the dash wont illuminate, UNLESS.... i disconnect the battery and reconnect, this seems to reset the system but again the same thing CLICK!

I bench ran the starter motor (all good), and the battery is good, checked all fuses, Any ideas before I start to strip the beast apart?
Thanks all

starter relay (which makes a connection between the key and the solenoid -
not all machines/vehicles have this) sticking/(latching?) and disconnecting all but the crank circuit (this provides total available power to only the cranking circuit)
will be a flip/flop relay - one circuit normally closed (open when energised) for the dash/ancillaries -- one circuit normally open (closed when energised) for the starter solenoid ..
something, either mechanical or electrical is causing it to latch -
most likely electrical as it disengages/de-latches when power is removed by disconnecting the battery ..
look for a short between it's coil's power source and probably the solenoid's feed from it (may even be an internal short in the relay itself )
most Automotive relays are flip/flop

 

[V8Druid]

I assume that after the click, the starter doesn't actuate/crank -- would suggest to me a fault internally in the starter relay, not feeding the solenoid - again assume your bench test included the solenoid on the starter, presumably a pre-engaged variety ?

 

[CPS]

What's your battery like first off?

 

[V8Druid]

What's your battery like first off?

says it's good Aiden ..... and presumably all the usual earth checks have been done

 

[bobthebuilder]

says it's good Aiden ..... and presumably all the usual earth checks have been done

Is ot good under load ,had one test perfect last week but put a single bulb on it , battery faded to 8v

 

[V8Druid]

Is ot good under load ,had one test perfect last week but put a single bulb on it , battery faded to 8v

have had the same Bob -- meters at 12.8v+, 'til you add a load - usual sign of a cell about to let go ... can be very confusing (and annoying)

 

[Mick-the-fitter]

Bad connection at terminal?