Starter? Motor running on.

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MetBlue
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Model: Elite 74 & Excel 92 (SEish))
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Year: 1974
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Starter? Motor running on.

Post by MetBlue »

An intermittent issue today.
Cold start, bit reluctant to fire. Holding key in crank position for maybe 5 seconds, but when key released, I could still hear a motor running in engine bay. Engine not yet running, and not being cranked, just a motor running. I THINK it was the starter motor.
Switched key off, even removed key and motor still running. !!! Starting to panic now, fearing something might be getting damaged.
Into boot, aiming to disconnect battery, but after about 10 seconds, it stopped - before I could disconnect battery. Time seemed about the same as the courtesy light delay.

Maybe a minute or so later, plucked up courage to switch key on again. All normal. Turned to crank and fired up immediately, completely normal. Quick drive and nothing seemed wrong at all.

Not fully studied wiring yet, but there's a link of some kind from the light delay to the Start Relay. My guess Is I've got a dodgy start relay that stuck, but happy for any other thoughts or confirmation.

Tony
What goes together.... Must come apart.

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MetBlue
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Model: Elite 74 & Excel 92 (SEish))
Colour: Metalic Blue
Year: 1974
Location: Northampton

Re: Starter? Motor running on.

Post by MetBlue »

Been thinking. If it was the starter motor, why wasn't the gear thrown out to the fly wheel? Unless I have two problems?
What goes together.... Must come apart.

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rbgosling
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Re: Starter? Motor running on.

Post by rbgosling »

That's odd. I take it you have an original starter motor, not some aftermarket one? It should only be able to spin when the solenoid has engaged the starter motor gear with the flywheel. The ignition switch activates the solenoid, but the solenoid itself closes the circuit for the starter motor. If the starter motor is spinning with the solenoid not activated, there's likely something dodgy in the solenoid, that's enabling it to close the circuit. Or a stray wire somewhere else, probably in the wires connected to the starter motor, that is bypassing the solenoid to activate the motor directly - but if that is happening that wire will get very hot, as the starter motor draws a lot of current. Hmm... maybe that's why it stopped after 10 seconds, whatever was causing the short just burned/melted?
"Farmer" Richard

1990 Lotus Excel SE (Lilith)
2022 MG MG5 EV (not due to be a classic for quite a few years...)
2011 Nissan Leaf (Ragly - EV pioneer, must be due to be a classic one day)

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