28-05-2020, 07:38 PM
I'm dredging my memory a bit here, but I recall that the "earthy" starter brush connects internally to the starter body via a riveted connection. Its not impossible for this to look OK and be nice and tight but have corrosion under the mushroom head, which raises the resistance of the connection. Bear in mind that starters can draw hundreds of amps and you need to keep resistance extremely low if it is not to drop significant voltage.
The only way to reliably test such a low resistance is to pass a known medium current through it, say 5 or 10 amps, and measure the voltage drop with a sensitive voltmeter. A car battery in series with a spare headlamp bulb will make a crude current source.
I resorted to soldering a copper link across one riveted joint, to save taking it apart.
The only way to reliably test such a low resistance is to pass a known medium current through it, say 5 or 10 amps, and measure the voltage drop with a sensitive voltmeter. A car battery in series with a spare headlamp bulb will make a crude current source.
I resorted to soldering a copper link across one riveted joint, to save taking it apart.