Start Whack

[John Lang]

Symptoms:
- dash lights up when key turned on but headlight does not (small running light does come on at first key position).
- pushing start button activates starter relay (click)and causes buzz (from fuel pump?) but does not crank engine at all.
- a few times, after waiting a few minutes, symptoms disappeared and engine cranked and started; the headlight came on but flickered at idle.
- once, I noticed all four flashers came on as I signalled a turn.

My diagnosis: 
Headlight flicker at idle indicates bad battery. It is 5 years old.
But multimeter reads 12.8V and, when it does crank, there is no hesitation.

Ignition switch needs cleaning.
Possible but wiggling the key does not reveal a short or gummed switch.

Load shed relay is shot.
But, swapped it with the horn relay and problem remained.

Dirty ground connection.
Cleaned battery terminals, ground connection to transmission housing, main ground connection under tank.
Result: no change.

Battery, ignition switch and starter motor (gah!) remain as possible culprits.

Other ideas?

[John Lang]

BTW -- I followed Johnny's '4 main causes of start whack' guidelines and am charging my old battery to the limit to determine whether its apparent healthy state is merely superficial.

[Martin]

Have you tried back spinning the starter. Or alternatively pull the starter and disassemble and clean the commutator. Also check the length of the brushes minimum length 6mm.
Regards Martin.

[bocutter Ed]

Load shed relay is shot.
But, swapped it with the horn relay and problem remained.

Could be the starter relay.

[John Lang]

Thanks, Martin and Ed. I can hear the starter relay click but will test whether it is actually sending current to the starter motor. Battery is now fully charged, according to the charger, and no happiness. Fuses are all good. Tomorrow, I'll do backspin and inspect the starter.

[kioolt]

Could be the starter relay.

A bad starter relay will not cause the headlight not to come on.  The starter will still have a ground for the load shed relay.  The symptoms are all pointing to a starter that needs cleaning or its brushes replaced.  An easy way to check is to tap lightly tap on the starter to see if the headlight flickers.  It will probably be a better check if it is done when the key is turned on and the headlight is not working.  If tapping the starter at this time and the headlight comes on that the starter is the problem.  Another way to check to see if it's the starter is when the headlight does not turn on is to ground the starter lead (DO NOT PRESS THE STARTER BUTTON) to see if the headlight turns on.  If the headlight turns on than the starter is the problem and if it doesn't than the starter is not the problem.   

[John Lang]

Thank you, kioolt. It was indeed the starter. I cleaned out the carbon and ordered new brushes. It runs again, hopefully until the new brushes arrive. Next time no start is accompanies by no headlight and 4-way turn signals, I will know what to check first.

[John Lang]

I should add that opening and cleaning the starter was not as scary as I feared it would be. Next time, though, I will try to notice a pair of shims on the floor BEFORE re-assembling and re-installing it.

[Martin]

It is a pretty easy job that should take under 90 min. It also helps if you run a smear of grease around the mating surfaces on reassembly. A mates bike starter had suffered from corrosion on the mating surface. It required considerable force and use of a cobbled up slide hammer to remove it. A loop of paracord around the mounting lugs is also helpful in locating a lever to pull the starter back while wriggling it.
Regards Martin.

[kioolt]

Its also a good idea to mark the ends and body of the starter before disassembly to make sure you put it back together correctly.  I usually use a punch and put one mark on the body and end on one end and two dots on the other end.  When putting back together align one dot with one dot and two dots with two dots.

[John Lang]

I used a felt pen and the marks absolutely saved me.

[The Mighty Gryphon]

+1 on the felt pen.  I use a Sharpie pen that has indelible ink.