'81 GS650G Starting

[tom203]

"The solenoid does not click when I hit the starter button."

What about that clicking from ignitor? Still there?? If yes, try unplugging ignitor and see if solenoid will click in when you press starter button.

[Rijko]

you only see 12.8 volt on the signal wire when pressing the starter button, right ... not all the time ?
Just checking ..

[Spirit380]

GS Starting

you only see 12.8 volt on the signal wire when pressing the starter button, right ... not all the time ?
Just checking ..

I have 12.8 volts at the signal wire, but it drops to around 3 volts when I hit and hold the starter button. The solenoid is now clicking with the igniter disconnected, I have tried tapping it with a small hammer, but no change, solenoid clicks and starter does not turn over.

Sounds like the solenoid is stuffed.

[tom203]

That drop to 3 volts when solenoid clicks in could also mean starter motor is drawing excess current causing battery to weaken. Have you tried "bridging" the big contacts on solenoid to see if starter motor will now turn? Current draw on normal starter is about 80 amps, so you'll see some sparking on your bridging device

[Steve]

It drops to three volts???? The obvious thing is that the battery can not supply what the starter is demanding. The not-so-obvious thing is that you still don't know if it's the battery or the starter at fault. The easiest way to determine which is at fault is to connect jumper cables to a NON-RUNNING vehicle and try again. If the voltage still drops below 10, your problem is likely the starter, but I'll put my money on the battery.

The suggestion to use jumper cables as a diagnostic tool has been suggested in posts #2 and #7, have not seen any results from that test. Until we see those results, anything else is just guessing.

.

[Spirit380]

I have charged the battery, it is new, and tried using jumper leads across the solenoid terminals and the starter does not turn. The solenoid clicks when starter button pushed. Starter motor must be stuffed?

[Rijko]

it starts to look that way.

You can remove the starter motor cover, connect the negative jumper lead to the chassis or negative battery terminal, and tap the connection on the starter motor with the positive jumper lead to be sure.

If the starter motor does nothing, you could whack the starter motor with a wooden hammer a few times, sometimes the carbon brushes are fouled and start working.

If all that fails, the started motor needs to be checked.
It can be cleaned and overhauled.

[tom203]

At this point, I would remove left side stator cover to check that nothing is jammed up in starter drive system..this would let you remove small idler gear and see if starter motor could now spin. Try tapping motor to wake it up!
Removing starter motor is nasty business, as carbs and camchain tensioner need to come off first. The shafty 650's share starter motors with the gs450 and 300 models (at least in usa versions)

[Spirit380]

Have removed the starter motor and it will not turn, by hand or with the battery, anyone rebuilt one?

[tom203]

Have removed the starter motor and it will not turn, by hand or with the battery, anyone rebuilt one?

If it is really stuck, I'd look for replacement. A competent auto place can replace bearings, brushes, turn commutator,etc. but sometimes these things are beat.

[Rijko]

agreed with Tom, if it's stuck you may need a replacement.
They are not hard to take apart and clean, so if you want to check
why it is not turning here's a nice movie from Rick's Motorsport Electrics.

[Spirit380]

Pulled the starter out and the problem was two of the magnets had come loose, one has broken up and seized the motor. Managed to get a second hand one from a GS650E but needed to change the mounting, not sure which way the motor should be running as it is going the wrong way and will not turn the engine over.

[tom203]

Holding the starter motor shaft facing you, the motor turns counterclockwise when the motor case is grounded and positive 12 volts is applied to terminal.

[Spirit380]

GS Starting

Holding the starter motor shaft facing you, the motor turns counterclockwise when the motor case is grounded and positive 12 volts is applied to terminal.

Must have put the armature in the wrong way round after dismantling it to check everything over and change the mounting, need to turn it around.