Starting problems

[CookMySock]

This IS step 1.

A load-test, yes I know but I don't have a load tester. The battery works perfectly well in another bike, as I have posted.

A known-good battery from another bike does not fix it. The problem remains, and is identical regardless of which battery is fitted.

Follow a logical trouble shooting sequence.
Next step AFTER this one is to test the charging system.
None of this is expensive or difficult to test.

But you need to check both. If you don't your new or existing battery (if it is still ok) could be poked buy a dud charging system adding additional cost.

If you aren't getting 13 volts at just off idle and about 14.5 at say 5k you have a problem in your charging system.

The charging current does seem a little lower than I expected, but I think it is a mistake to pursue a fault in the charging circuit just yet.

It is abundantly clear there is something amiss in the starting circuit. Two different batteries, one of them brand new, gives exactly the same result.

I found an article on korider, and it suggested that I might have a stuck or worn starter brush, so I think the starter can come off and be disassembled.


Steve

[warewolf]

Battery connections that I can see are clean and tight, and passing nearly 200amps.

Just went and tried it right now - bike starts perfectly. Stop it. Try again - won't start.

We recently had to overhaul the starter in our 4wd. Sometimes, more and more often, it wouldn't turn the engine over. Roadservice fellah recorded 350A when it wasn't turning.

Many moons ago the starter in my Triumph got dirty contacts/bushes/whatever. Sometimes the starter wouldn't turn from the position it was in, usually on a cold morning or late at night (ie when battery was weakest). Put the bike in 6th gear, bump the rear wheel to turn the starter motor a little bit, then it would start normally. Again, starter clean-up fixed the issue.

[gwigs]

sounds like starter motor brushes are worn ..happened to a holden I owned.
It used to play up once warm..

[FJRider]

The charging current does seem a little lower than I expected, but I think it is a mistake to pursue a fault in the charging circuit just yet.

It is abundantly clear there is something amiss in the starting circuit. Two different batteries, one of them brand new, gives exactly the same result.

An auto electrician would probably be the best bet ... just to confirm where the problem lies. But I guess you already know that.

[CookMySock]

An auto electrician would probably be the best bet ... just to confirm where the problem lies. But I guess you already know that.

My bet now, is it's bushes, brushes, and/or a commutator clean-up. I'll haul it apart (usually trivial) and then it's usually pretty obvious what the problem is. Then take the box of bits down to the auto electrician for parts.

I might try a car battery directly onto the starter with some jumper leads. If THAT doesn't work, then its pretty obviously the starter motor.

Steve

[FJRider]

My bet now, is it's bushes, brushes, and/or a commutator clean-up. I'll haul it apart (usually trivial) and then it's usually pretty obvious what the problem is. Then take the box of bits down to the auto electrician for parts.

I might try a car battery directly onto the starter with some jumper leads. If THAT doesn't work, then its pretty obviously the starter motor.

Steve

Had you thought it may be a fuel issue, if fuel isn't getting into the carbs fast enough ...

A fair bet of yours maybe, but before the teardown ... If you get the parts from him, I doubt if he would charge for testing ...

[CookMySock]

Had you thought it may be a fuel issue, if fuel isn't getting into the carbs fast enough ...

A fair bet of yours maybe, but before the teardown ... If you get the parts from him, I doubt if he would charge for testing ...

No, it's nothing to do with fuel, UNLESS massive amounts of it are pooling in the combustion chamber and liquid-locking it.

Theres nothing complicated inside a starter motor. It has brushes and bearings. One of those two things will be stuffed.

I don't know what parts I need until I pull it apart. Starter brushes are just brushes - theres nothing scientific or model-specific about them. I just file them to the correct size and slide them in and screw them down. Trivial.

Bushes are a little more involved, but I bet they can get any size at all, and if they cant, then my mate with the lathe can make me some.

The hardest part by far is getting the fairings off without marking them or losing the screws, and stopping the oil running everywhere when I pull the starter motor out.

Steve

[vifferman]

I've heard summat similar before, with the starter being faulty and sucking away the current.

I wonder if it could be the starter motor, perhaps?

[TripleZee Dyno]

No, it's nothing to do with fuel, UNLESS massive amounts of it are pooling in the combustion chamber and liquid-locking it.

Theres nothing complicated inside a starter motor. It has brushes and bearings. One of those two things will be stuffed.

I don't know what parts I need until I pull it apart. Starter brushes are just brushes - theres nothing scientific or model-specific about them. I just file them to the correct size and slide them in and screw them down. Trivial.

Bushes are a little more involved, but I bet they can get any size at all, and if they cant, then my mate with the lathe can make me some.

The hardest part by far is getting the fairings off without marking them or losing the screws, and stopping the oil running everywhere when I pull the starter motor out.

Steve

Going by your first post I would make sure the charging system is working properly before anything else.
11v volts at idle is way too low. Wont matter how good your starter motor is, 11v isnt a happening thing.
Current flow in the loom earth and nothing in the battery leads sorta points to the charge system being OK but between regulator and battery there is a problem.
Check o/p at regulator and compare with whats at the battery terminals.
Any more than .3-.5 v difference and you have a wiring fault
You want a minumum of 14v at the battery.
Do these tests at around 3-4000 rpm
Good batteries can "recover" a bit when given a rest, could be whats happening here
good luck

[cowpoos]

Going by your first post I would make sure the charging system is working properly before anything else.
11v volts at idle is way too low. Wont matter how good your starter motor is, 11v isnt a happening thing.
Current flow in the loom earth and nothing in the battery leads sorta points to the charge system being OK but between regulator and battery there is a problem.
Check o/p at regulator and compare with whats at the battery terminals.
Any more than .3-.5 v difference and you have a wiring fault
You want a minumum of 14v at the battery.
Do these tests at around 3-4000 rpm
Good batteries can "recover" a bit when given a rest, could be whats happening here
good luck

Yep...thats where I was heading with my thoughts...but I think if its not a doodgy earth or power wire to the starter which I think it is personally [from what he has described]...he's heading down the right track with the starter...

[CookMySock]

Going by your first post I would make sure the charging system is working properly before anything else.
11v volts at idle is way too low. Wont matter how good your starter motor is, 11v isnt a happening thing.

Yes that 11V is the first thing that struck me as odd. Considering that is the first thing I checked, I probably should have stopped "diagnosing"(sic) there.

This morning first thing it wouldn't start, so I jumper lead it to the car - instant start. So I left the fairings on.

It took an hour or so on the automatic charger before I get a green "charged" light. Bike then starts perfectly, BUT when the engine is running the charger reverts to "charging" amber light, and goes back to green "charged" a few seconds after I kill the engine.

Current flow in the loom earth and nothing in the battery leads sorta points to the charge system being OK but between regulator and battery there is a problem.
Check o/p at regulator and compare with whats at the battery terminals.
Any more than .3-.5 v difference and you have a wiring fault
You want a minumum of 14v at the battery.
Do these tests at around 3-4000 rpm
Good batteries can "recover" a bit when given a rest, could be whats happening here.

That's very interesting and useful observations. Thank you.

I will pull the sidecover off and check over the wiring. Perhaps there is a fuse in the charging circuit blown somewhere.

Steve

[CookMySock]

Ok stator output anomoly.

Pull plug from stator to rec/reg, and test ;

Phase to phase (any combination) 70V AC @5,000rpm. All good.

Phase to Phase ohms (engine stopped, any combination) , 1.2ohms ish. All good.

BUT it should be open-circuit any phase to ground, and it aint. It's only a few ohms.

Engine idling 2,000rpm ish, test ;

Phase 1 to frame ground, 30V AC ish
Phase 2 to frame ground, 30V AC ish
Phase 3 to frame ground, 3V AC ish !

Shorted phase 3 to ground inside the stator? Damn.

Is this why theres a 10amp current loop through the loom ground and the battery ground? Testing now to see if that current loop is DC or AC..... edit: there is about 10A AC flowing in the battery ground strap!

Pulled stator off ;

Phase 1 to frame ground 1.2 ohms
Phase 2 to frame ground 1.2 ohms
Phase 3 to frame ground 0.7 ohms

Short test meter leads - 0.5 ohms.

Stator looks like its been hot. Fark, who wound this?? it doesn't look right to me. Pic to follow. Looks like someone wound a bit then hit it with the hammer, then wound a bit more and hit it again, and so on. Geesh.


Steve

[Fatjim]

Phase 1 to frame ground, 30V AC ish
Phase 2 to frame ground, 30V AC ish
Phase 3 to frame ground, 3V AC ish !




Steve

I assume this is with all the plugs back in and not some hack to get the alternator supplying current.

I would guess the Reg/Rec is pulling down the voltage.

[The Stranger:Me]

A load-test, yes I know but I don't have a load tester. The battery works perfectly well in another bike, as I have posted.

You have a head light.

The charging current does seem a little lower than I expected, but I think it is a mistake to pursue a fault in the charging circuit just yet.

It is abundantly clear there is something amiss in the starting circuit. Two different batteries, one of them brand new, gives exactly the same result.

Ok stator output anomoly.

Pull plug from stator to rec/reg, and test ;

Phase to phase (any combination) 70V AC @5,000rpm. All good.

Phase to Phase ohms (engine stopped, any combination) , 1.2ohms ish. All good.

BUT it should be open-circuit any phase to ground, and it aint. It's only a few ohms.

Engine idling 2,000rpm ish, test ;

Phase 1 to frame ground, 30V AC ish
Phase 2 to frame ground, 30V AC ish
Phase 3 to frame ground, 3V AC ish !

Shorted phase 3 to ground inside the stator? Damn.

Is this why theres a 10amp current loop through the loom ground and the battery ground? Testing now to see if that current loop is DC or AC..... edit: there is about 10A AC flowing in the battery ground strap!

Pulled stator off ;

Phase 1 to frame ground 1.2 ohms
Phase 2 to frame ground 1.2 ohms
Phase 3 to frame ground 0.7 ohms

Short test meter leads - 0.5 ohms.

Stator looks like its been hot. Fark, who wound this?? it doesn't look right to me. Pic to follow. Looks like someone wound a bit then hit it with the hammer, then wound a bit more and hit it again, and so on. Geesh.


Steve

What the fuck did I say? - There IS a clear logical sequence to follow.

[CookMySock]

I assume this is with all the plugs back in and not some hack to get the alternator supplying current.

I would guess the Reg/Rec is pulling down the voltage.

No, that was with the rect/reg disconnected - there was no current flowing. Those are AC voltages with respect to the bike frame/chassis.

I've got the stator out. It's been hot for sure.