wystad

Help...............
I'm a time served electrical engineer (Power) pulling his hair out over an intermittent fault.
I have a completely rebuilt 1968 GT390 Eleanor recreation.

1) The car will not start on the key, all that is heard is the click of the starter solenoid.
2) Battery okay but jumper battery also used - no effect.
3) The starter motor was removed and run up and bench tested satisfactory.
4) A short from the battery +ve on the motor to the starter connection finally got the motor started after a few attempts.
5) +ve battery to starter, -ve battery to chassis and engine earth checked for mechanical integrity okay.
6) Checked 12V onto starter solenoid upon key activation
7) Replacement starter bought and fitted, starts and runs for a week then reverts to no starting.
8) Happens when engine is hot or cold
Happy to take any ideas, suggestions and theories

Gun Jam

well if its not voltage sag due to a bad battery or cable its probably a crap starter.

Are you running a mini starter like for a t5 trans or is it a fullsize starter?

I had a crap mini starter that would do the same thing when the engine was hot. I spent like 300.00 on a ford racing mini starter with like 3:1 reduction and its been excellent for many years.

Starfury

Have you checked connections for looseness or corrosion? It's odd that a replacement solenoid worked for a while before the problem resurfaced, which makes me think that a connection was wiggled appropriately during install, then worked it's way loose.