Starter relay OR Starter Motor? (Intermittent starting issue when warm)

[heath_AU]

Hi All

Have not posted on here in ages. Have been having far too much riding of course

Well recently i had my baby girl (2008 FZ6N) start having an issue where intermittently (maybe 1 in 3) times when i would go to start her while she was warm/hot I get just a relay/solenoid click and NO cranking. While i hold the button down the check engine light appears but I think this is normal.

I figured out that if I put the bike in gear and rolled the bike back and forward turning the engine over slightly, it starts everytime (albeit slightly sluggishly)

I have a brand new battery (MotoBatt) and the last one of those was still perfectly good after 5 years of daily riding and as it starts perfect every time cold (and a perky start with no hesitation) i am convinced the battery is not the issue.

The bike unfortunately did endure some salt water in a freak incident once (had an ocean wave actually break over me while riding) and this triggered some unusually aggressive corrosion (yes i know now I should have washed her immediately) so it would not be a surprise to see some electronics failing prematurely.

She has 130,000km on her and has been frequently serviced so I am thinking either the starter relay is playing up or (more likely) its the brushes in the starter motor (which would explain the rolling/turning method of starting her)

Any thoughts?

I have removed all the wiring for both the starter and main relay/fuse and cleaned them (much oxidation material was removed) but this yielded no change

Cheers

Heath

 

[gulfpete]

I've had the same happen in a few cars from bad connections, the connectors get hot when the starter is cranking, usually the earth on the battery but relays get hot too if they're corroded inside.

 

[VEGASRIDER]

I had similar symptoms and it turned out my brushes in my starter were worn. About $30 to replace the brushes. Next time, if your bike doesn't crank. Try push starting the bike, it should start. I assume you know how to do that.

 

[heath_AU]

the cables shouldnt get hot when cranking - if they do it means they are carrying way too much current or you have been cranking it way too long
when i said warm/hot i meant the engine - not cables

and all connectors are clean and free of corrosion

 

[TownsendsFJR1300]

Couple things you can do to narrow it down.

Apply 12 volts direct to the starter (perhaps from another battery). If it turns over ALL the time normally, it's NOT the starter.

If you have a volt meter, check the voltage AT THE STARTER WHEN CRANKING. It shouldn't drop much.


Checking voltage coming OUT of the starter relay should be 12.8 volts or so. If NOT, the relay is likely toast.


With the mileage you have on the bike, it could very well be either.

.

 

[TownsendsFJR1300]

Any updates?

 

[heath_AU]

No further updates just yet. Have heaps on and as its only an intermittent issue it's not really top of the list.
The test start using an external battery could be the way to go. I still have the last battery in the shed. It was still strong as when i replaced it and made sure it was fully charged. Will put it on a trickle charger now and see if I can give it a test later this weekend.
Cheers.

 

[heath_AU]

I have since ordered a starter motor rebuild kit instead - i am convinced the starter relay is not the issue

And if i am wrong at least i will also have an overhauled starter motor and only $45 out of pocket

 

[heath_AU]

***UPDATE***

OK - Sorry for the delay my treasured comrades
I had a win on the weekend. Well by win i mean i got off my ass (or away from the PS4) and decided to have a look at the bike,
Looks like i fixed this issue and the cause of it was ......... wait for it ......... SHAGGED STARTER MOTOR BRUSHES
The service manual says to remove starter motor i needed to remove the tank and the throttle bodies but i managed to do it by removing only the air box.
Basically the only tricky part is getting to the 2 bolts that hold the starter to the block. You will need an long extension bar on your socket to reach them but there are some gaps through the throttle bodies that allow perfect access from above. (Remember to always cover your throttle inlets with a rag to avoid dropping anything in them)
I have attached a photo of the old brushes VS the new. You will see what i mean.

I believe the issue was the B brush was so worn that it was not in contact with a section of the coil/motor assembly that was slightly more worn in one section (ie. the contact surface was just slightly out of reach of the brush)
What do you think?

 

[TownsendsFJR1300]

***UPDATE***

I believe the issue was the B brush was so worn that it was not in contact with a section of the coil/motor assembly that was slightly more worn in one section (ie. the contact surface was just slightly out of reach of the brush)
What do you think?

If brush "B" is fully extended and not hanging up(that would be bad too) , you found the issue.

You should be good now, great job and thanks for the update..


That coil spring has to keep good pressure against the brush and ultimately the armature, which it wasn't...


.

 

[heath_AU]

Hi All

*deep breath*

OK - well here is the next update in this saga.

Seems when i put the starter motor together some washers were dislodged from the end of the shaft by the magnets in the housing and as a result eventually they found their way around to the brushes and caused a short. The symptom being no starting - although surprisingly they did not blow the starter relay fuse/s.
Well at the time I was convinced it was the starter relay (as everyone kept telling me) so i shelled out the cash and ordered a new (genuine one) express.
You can imagine my heartbreak when I installed this only to find the same issue.

SOOOOO then i figured it must be the starter motor again as I know my battery is new and very strong.
I pulled it apart - saw the washers and was convinced i had it fixed.
Installed starter and was devastated to then find the starter motor was spinning but it was free-wheeling and not turning the motor over
So then my attention turned to the starter clutch. Pulled off the generator (bit of an involved job) and then i figured out the problem was my starter motor was spinning in reverse.
This was totally confusing as it was not possible to connect the starter in reverse polarity (unless you somehow managed to install the battery backwards)
A bit of googlling later and I realised what I had done, When re-assembling the starter motor I had unknowingly assembled the centre (tube) section in back to front (or end for end)
As this section contains the permanent magnets for the motor, doing this will result in the motor running in reverse and as a result failing to engage the starter clutch.
(See attached image from the service manual)

I am writing this post in the hope that I may save one of you the hassle of going through what I did - as this part in the starter looks like it can go in either way due to its symmetrical design

Anyway - i finally got there in the end - but not before investing my entire weekend. Hope this post saves someone a lot of hassle

 

[ronandc]

I've been having all the same issues - only getting the relay click and check engine orange light - had the 'B' brushed very worn down and hacked together a way to make it press to the motor more - then after putting everything back together still got nothing from the starter when trying to start.
Sometimes I can get a grinding noise from it if I tap the starter motor when hitting start. I replaced the relay too just in case. I'm nearly positive I aligned the motor the right way when reassembling the starter, I didn't think it was even possible to do that wrong actually! and likewise the rotation of it in the tube I believe I did right using the notched guidelines on the exterior of the starter motor casing.
If a new brush assembly doesn't fix the issue then I dunno what to do. Bike barely push starts now actually

 

[TownsendsFJR1300]

I've been having all the same issues - only getting the relay click and check engine orange light - had the 'B' brushed very worn down and hacked together a way to make it press to the motor more - then after putting everything back together still got nothing from the starter when trying to start.
Sometimes I can get a grinding noise from it if I tap the starter motor when hitting start. I replaced the relay too just in case. I'm nearly positive I aligned the motor the right way when reassembling the starter, I didn't think it was even possible to do that wrong actually! and likewise the rotation of it in the tube I believe I did right using the notched guidelines on the exterior of the starter motor casing.
If a new brush assembly doesn't fix the issue then I dunno what to do. Bike barely push starts now actually

I would "bench test" the starter and see how/if it operates properly.

If that works, hook up the positive from the harness to the starter, starter NOT bolted in but grounded and see if the starter button activates the starter as it should.

I'd also monitor the battery drop down voltage when activating the starter (installed)

You need to isolate where the problem is specifically, IE starter, relay, drive gear (inside the engine-that the starter engages with, etc..


.
.

 

[Motogiro]

I'd also monitor the battery drop down voltage when activating the starter (installed)

You need to isolate where the problem is specifically, IE starter, relay, drive gear (inside the engine-that the starter engages with, etc..

Exactly! ^^^^^ do this test first.
You also might have a bad commutator or winding on the armature.

 

[TownsendsFJR1300]

Forgot but to rule in or out the starter, you can "hot wire" the starter direct to the battery.

You'd be by passing EVERYTHING but the starter. If it cranks, you know the starter / engine is good. If it acts up, you know the starter or engine gear is at fault..

.

 

[Motogiro]

Forgot but to rule in or out the starter, you can "hot wire" the starter direct to the battery.

You'd be by passing EVERYTHING but the starter. If it cranks, you know the starter / engine is good. If it acts up, you know the starter or engine gear is at fault..

.

Great idea! Just make sure it's in neutral.