Desperate Need of Starter Help

[gasser]

What did I do? My starter was working 95% of the time but would sometimes disengage from the motor before the motor started. I tried stretching the little spring in the bendix but that made it worse. The starter quit engaging at all. It spins fine when you hit the button but doesn't even try to turn the motor. I thought I screwed up the spring so I installed a new bendix but nothing changed -the starter spins great but still doesn't try to engage the motor. What have I done?

 

[BSM2]

What did I do? My starter was working 95% of the time but would sometimes disengage from the motor before the motor started. I tried stretching the little spring in the bendix but that made it worse. The starter quit engaging at all. It spins fine when you hit the button but doesn't even try to turn the motor. I thought I screwed up the spring so I installed a new bendix but nothing changed -the starter spins great but still doesn't try to engage the motor. What have I done?

Mine was engaging 90% of the time, but not holding.
Especially at cold starts when starter has to work a little bit longer, it disengage after engaging and stretching did not help.

It helped to give more play between bendinx and flywheelgear. 1 have removed one shim 0.2mm.
Now it is holding better.
However it is still making a lot of noise.

 

[Neil E.]

Stretching the bendix flyweight spring only helps with initial engagement problems. If it is stretched too large, the sprag elements won't hook up to drive the gearing. Then you get a quiet motor spin and nothing else happens.

It's a tricky balance of forces. Rotation drives the camming action. As soon as the engine fires the bendix return spring shoves the unit back to home position.

The issue might be that the engine fires without actually catching enough to run.

Gasser, how does the bendix feel when you operate it by hand?

Old bendix with stretched spring = no action due to loss of sprag engagement?
New bendix with stock spring = no action due to firm flyweight spring?

Maybe the best solution is BobT250's Honda sctooter bendix mod.

 

[shang]

I did the Honda scooter mod on my '13 and I have positive engagement every time. I have hundreds of starts on it.

 

[gasser]

Stretching the bendix flyweight spring only helps with initial engagement problems. If it is stretched too large, the sprag elements won't hook up to drive the gearing. Then you get a quiet motor spin and nothing else happens.

It's a tricky balance of forces. Rotation drives the camming action. As soon as the engine fires the bendix return spring shoves the unit back to home position.

The issue might be that the engine fires without actually catching enough to run.

Gasser, how does the bendix feel when you operate it by hand?

Old bendix with stretched spring = no action due to loss of sprag engagement?
New bendix with stock spring = no action due to firm flyweight spring?

Maybe the best solution is BobT250's Honda sctooter bendix mod.

Engine can't fire because it never turns over - starter turns great but now it never engages the gear on the flywheel to spin the motor. I did do the Honda bendix mod and both the old bendix and the new one seem to work fine but still no engagement with the flywheel. I can't see how it wouldn't have to work.

 

[liamthom]

After i cleaned my bendex out with toothbrushes q-tips and break cleaner it did not engage it had plenty of grease too. I had to have it spin a little, i think the grease was not spread out well enough. Also i feel like a new Bendix's spring might be a bit stiff, maybe using the estart a little every now and then will losses it up but i don't know for sure.

 

[Neil E.]

Engine can't fire because it never turns over - starter turns great but now it never engages the gear on the flywheel to spin the motor. I did do the Honda bendix mod and both the old bendix and the new one seem to work fine but still no engagement with the flywheel. I can't see how it wouldn't have to work.

What happens if you jump from a car battery? That might accelerate the camming to start the engagement. We need to be clear on one thing, is it a quiet motor spin only or is there a slight gear clash sound?

Is your Honda mod using the stock Honda flyweight spring? Have you changed anything else like the thickness of the ignition cover gasket? What are you using to lube the inside of the Bendix unit? Are you testing in the garage at room temperature?

 

[gasser]

What happens if you jump from a car battery? That might accelerate the camming to start the engagement. We need to be clear on one thing, is it a quiet motor spin only or is there a slight gear clash sound?

Is your Honda mod using the stock Honda flyweight spring? Have you changed anything else like the thickness of the ignition cover gasket? What are you using to lube the inside of the Bendix unit? Are you testing in the garage at room temperature?

Starter spins free (no gear clash or engagement), stock honda flyweight spring, ignition cover hasn't been removed since starter was working near perfectly, sprayed new bendix liberally with white lithium grease, temperatures in the 60s.

 

[Biff]

You sure inner helical gear on bendix is ok?

 

[shang]

Maybe pull the starter and hit the button to see if the bendix it operating properly?

 

[Neil E.]

sprayed new bendix liberally with white lithium grease, temperatures in the 60s.

It could be the grease causing it to hang up. I recommend you remove the starter motor and small cap, then lift out the Bendix unit (watch for shims).

Hold the Bendix open and wash it out with WD40/varsol/brake cleaner etc. Make sure you slide the covers open to get at everything so all the grease is removed. Blow it out with compressed air, then oil it with a light motor oil. Re-install and let us know what happens.

 

[Neil E.]

Maybe pull the starter and hit the button to see if the bendix it operating properly?

This will only confirm that the starter motor turns. The GG Bendix is not built into the starter head like you would find in an old automotive starter. I had them on a 47 Frazer and a 54 Studebaker. A modern shift fork style starter is more reliable than a plain Bendix type starter. I remember having to rock the Studebaker once (in gear) to move the flywheel a bit so the starter teeth could engage.

 

[gasser]

I may have found the problem. I did not mention that when I first started working on my bike to make the electric start work better I actually partially disassembled the starter motor itself. It seemed to go back together just fine but it appears that it now runs backwards. That would explain why the original bendix suddenly quit working altogether and the new one didn't do any better. Any suggestions on what I did to screw it up?

 

[pscook]

I may have found the problem. I did not mention that when I first started working on my bike to make the electric start work better I actually partially disassembled the starter motor itself. It seemed to go back together just fine but it appears that it now runs backwards. That would explain why the original bendix suddenly quit working altogether and the new one didn't do any better. Any suggestions on what I did to screw it up?

Silly question, but have you switched the wires around? It's a DC motor, so that is the only way that I (not being an electrician) could conceive running an electric motor in reverse. I have rewired my starter, but I seem to remember all of the wires being black. It is worth the time to investigate wire routing. The wire from the solenoid (positive) should run to the bolt on the side of the starter motor, and the ground should run to the case of the motor.

 

[Neil E.]

I agree with Phil, you've got the polarity backwards.

 

[gasser]

I don't understand this - I didn't do anything to the wiring but unbolt the big power lead that goes to the starter. I then removed the 2 long bolts that hold the starter together and pulled the two ends off. Next I inspected the armature and put everything back together. Somehow doing just that reversed the polarity on the starter so it ran backwards. I took it apart again and now it's spinning in the right direction and engages the flywheel. Neither time did I do any changing inside the starter motor - wiring wasn't touched, brushes weren't removed - nada - the 2 bolts were removed allowing the motor to be separated into 4 pieces: 2 end caps, armature, and magnet sleeve/case that surrounds the armature. Everything looked ok so I jut put it back together. Same thing twice - first time messed it up second time fixed it - go figure.

 

[Neil E.]

Haven't heard of it before, but strange things do happen. Nice to see it was a simple "fix".

 

[eastenn]

I don't understand this - I didn't do anything to the wiring but unbolt the big power lead that goes to the starter. I then removed the 2 long bolts that hold the starter together and pulled the two ends off. Next I inspected the armature and put everything back together. Somehow doing just that reversed the polarity on the starter so it ran backwards. I took it apart again and now it's spinning in the right direction and engages the flywheel. Neither time did I do any changing inside the starter motor - wiring wasn't touched, brushes weren't removed - nada - the 2 bolts were removed allowing the motor to be separated into 4 pieces: 2 end caps, armature, and magnet sleeve/case that surrounds the armature. Everything looked ok so I jut put it back together. Same thing twice - first time messed it up second time fixed it - go figure.

I've read about 10 threads (including the 11 pager) and this is the first I have seen something about the starter spinning the wrong direction..and I'm pretty sure I did the exact same thing to mine last night. Took the starter apart just like you described, put it back together (didn't think much of it).. pulled the bendix and stretched the spring and kept tinkering and never could get another engagement. At least before it would partially engage. I wondered if the starter could be spinning backwards but I didn't think so because I wired it back exactly the same.. I'll find out tomorrow! Thanks for posting this up.

 

[Phaeton]

I bought a starter out if a 2014 Suzuki drz400. Same numbers as my starter but it ran backwards. Switched wires all us good

 

[shang]

I helped a friend rebuild his KTM starter and when we assembled it we got the timing wrong. It would spin backwards. If you've had it apart, it can bolt together 180 degrees out.