Starter motor failure in a big way!

[Green Boy]

Hi,

(2004 1150 gsa)

Went to start the bike tonight to ride home. That worked but the starter motor would not disengage and effectively ran live even with the engine on or off.

I kicked it a few times to see if I could disengage it - it didn't. I then pulled every fuse out of the fuse box and some of the relays to try to stop it. That didn't work.

In fact the only way it did stop was when it flattened the battery!

My questions are this:

1. WTF happened?
2. Has this happened to anyone else?
3. Do I need to replace the starter motor? (i'm guessing yes)
4. Is it likely to have buggered anything else (fly wheel, wiring lume......)

Based on the fact that the starter motor is likely to be goosed, any suggestion where to get one from a few days before Xmas? (Not Santa)

Any thoughts greatfully received.

In a word......Arse!

 

[fatnfast]

Sorry to hear about your woes. I would say there is a fair chance you will be able to strip and clean the starter, theres a good thread at the top of the 1150 stuff. Sounds like its just gummed up.
Its easy to remove, and you can then inspect the teeth on the fly wheel, hopefully you will not have damaged them.

 

[daveg]

I've got a secondhand one if you're interested and can pick up from Reading.

 

[Green Boy]

Hi Fatnfast,

Thanks for the thoughts. I'll take it to pieces on Saturday morning and see what state it's in.

Daveg: Thanks, depending on what state mine is in, I may take you up on that. For reference, how much do you want for it and what sort of state is it in? PM me if easier

 

[Uncle Crumpet]

solenoid, starter relay or start button. Did it keep turning over the engine or just making noise?

 

[Green Boy]

solenoid, starter relay or start button. Did it keep turning over the engine or just making noise?

it kept turning over. Thinking about it this morning as walked to the station was probably solonoid. Sound reasonable?

 

[alistairl]

it kept turning over. Thinking about it this morning as walked to the station was probably solonoid. Sound reasonable?

I've only had the 1100 starter apart and it can goo up - if it was turning quickly enough then a nice clean up should do the business - don't put in anything heavy grease wise.

A.

 

[Timolgra]

Check the relay, it used to be a fault with F650s

 

[flatdog]

it kept turning over. Thinking about it this morning as walked to the station was probably solonoid. Sound reasonable?

Solonoid probably not.
(my understanding)
It's purpose is to fling the starter cog into the flywheel while the starter motor shaft is spinning.
If the S/M is turning the engine over with the ignition off.
I'd be more inclined to look for a short to earth on the S/M or the exciter wire - small spade connector next to the positive lead on the S/M

 

[Steptoe]

Check the relay, it used to be a fault with F650s

And the K series bikes.

 

[warmshed]

The fault is that the starter solenoid is operated. The solenoid engages the starter pinion THEN applies power to turn the starter.
This could be either a battery voltage on tag50 of the starter motor, (the thin black wire) that comes from the starter relay, or a fused contact in the solenoid,

Remove the black wire to the starter, if it still tries to turn the motor then the fault is the solenoid.

If it does not then you have a battery condition on the balck wire from the start relay. unfortunately this is an un-fused supply, so would not be affected by you pulling out the fuses.

The start relays can fuse their contacts so worth a check. Pull out the relay, if you prise open the relay cover you may be able to part the relay contacts and clean them up with a needle file though a new relay would be best. (have repaired a moto guzzi relay this way and worked on for ages afterwards.)

These are the two most likely scenarios so have a go and let us know. Dave.

 

[Green Boy]

Ok so after a 'festive' 15 mins on Christmas Eve studying a wiring diagram and several forrays into the garage with a multimeter, I've got to the bottom of this.

The route cause of this problem was a failed Load Relief (LR) Relay. After I pulled the starter relay out and there was still +13v on the tag 50 even when the ignition was off, I started to look elsewhere and discovered the only place it could still draw power from was a failed LR relay.

From the diagram, if the relay fails in the closed position, it acts as if the starter button is continually being pressed and hence the starter motor continually fires.

In the interim, I've ordered a reconditioned starter motor from Motorworks as whilst mine still works, the magnet glue isn't going to last much longer. Other than the inconvenience of a trip home on a recovery truck the other night, it was a useful exercise to understand how the ignition system works.

Thanks for all the help and suggestions. Now just need to resurrect the dead battery and I'll be back on the road.

Merry Xmas and all the best for 2012!

The fault is that the starter solenoid is operated. The solenoid engages the starter pinion THEN applies power to turn the starter.
This could be either a battery voltage on tag50 of the starter motor, (the thin black wire) that comes from the starter relay, or a fused contact in the solenoid,

Remove the black wire to the starter, if it still tries to turn the motor then the fault is the solenoid.

If it does not then you have a battery condition on the balck wire from the start relay. unfortunately this is an un-fused supply, so would not be affected by you pulling out the fuses.

The start relays can fuse their contacts so worth a check. Pull out the relay, if you prise open the relay cover you may be able to part the relay contacts and clean them up with a needle file though a new relay would be best. (have repaired a moto guzzi relay this way and worked on for ages afterwards.)

These are the two most likely scenarios so have a go and let us know. Dave.

 

[warmshed]

Cant see how the LR relay failed in the operated position, would cause the fault but if any of the tags were touching tag 85, of that relay, that would cause the fault.
I believe the load relief relay should be operated when the ignition is on and releases only while the start button is pressed. If the contacts fused together it would not operate the starter.
(though I could be mis-reading the diagram.)