Sensitive Starter motor Woes !!!

Hi all...
Can anyone make anything out of a problem I've got..
Basically an Intermitent starter motor..(defender 300tdi)

Exciter wire (signal wire) has a constant 10.3 volts on the multi metre when ignition key is against the spring.
Terminals all good etc .

Sometimes it starts sometimes it doesnt. When it doesnt start, if I leave it for an hour and come back, it sometimes starts...

If it doesnt start, bridging the terminal on the solinoid to the main live going into the starter motor and it starts on the button every time....

Are the solenoids that sensitive to the odd couple of volts ???

This is the second starter (all be it second hand) I've tried..
Does the same with both...

any suggestions ?

Thanks all.

Solenoid needing cleaned/rebuilt.

Connections to solenoid loose dirty.

Had this with the Disco a number of years ago - kept a stick in the car, if it didn't start I would give the starter a belt with the stick and then it would start everytime.

sounds like the switch is faulty to me, or the wirign - 10.3 volts is very low. With a high impedance multimeter on it, this doesn't seem that low. Put the solenoid in place, which will draw some current, and the voltage will be much lower - measure it with the connection in place see what it shows.

Thats my thoughts anyway

Mucky or corroded conections. Take em all off and clean em up.

Yeah all clean etc. Arsed if I know why the exciter wire has an intermittent voltage drop... checked, rechecked connections, changed relays (several times!)
Batteries all good etc.

Took a feed directly from the ignition barrell to the solenoid..Good as gold.

hmmmmmmmmmmm ( head scratch!!!)

I'll assume there's a relay somewhere between the ign switch and the solenoid... if so, check the contacts on that

Yeah did all that, put new relay in etc etc. Just can't trace it ! ho hum !

ive found that the rubber that protects the the live wire from my batt to the starter motor had perished and consequently the terminal had become corroded, gave it a jiggle around and tightened it up and it fixed a problem similar to yours.

Thanks for that...
If it doesn't start from the solenoid, jumping the solenoid from the live cable going into the starter motor starts it instantly, which means the cable to the battery is all good.

it's Def a voltage drop somewhere from the relay to the solenoid but am arsed if I know where or why ! lol