Motor will not start (pics)

[bassarama]

Hey guys

Before I even started doing the decarburization with Seafom, I found another problem with the motor…I couldn’t start it. At first, the starter motor would not even turn so I thought the batteries were low on charge, I plugged the battery charger on 12 volts and after a few minutes I got to turn the starter motor, the problem is that the starter motor turns but its dog gear doesn’t engage on the fly wheel, I removed the fly wheel cover to look inside.




Here, I’m turning this gear by hand and it has resistance, should it turn freely?



The whole gear assemble appear to be in excellent shape, I sprayed it with Lithium gear and installed it. Again, the starter motor turns but it doesn’t engage. I think I have a bad starter motor…



Darn, now I believe these things go bad sitting around for long time, actually I’m glad I’m finding these problems right here at home.

Comments and suggestions are very much appreciated. Thanks

Joe

[eight]

That's fairly common. All I've ever done to fix it is to have the starter rebuilt. If the flywheel and gear were not covered you could lift it up with a screw driver to get it to engage.

Also, make sure your batteries are charged. Weak batteries may not spin the starter fast enough to force the gear up.

[tsubaki]

That portion of the starter can cause the problem, I just replaced mine cause I could see a little smoke come off it when it would sorta drag on occasion. Lithium actually gets sticky over a period of time, I stopped using it.
The starter itself could be the problem, over time and use the particles from the brushes and windings can coat or build up in the starter causing some insulating qualities between the brushes and their contact surfaces. Just disassemble it, brush it out, reassemble and test. If it improves or stops the problem, buy a new starter and replace at your convience.
Don't rule out the starter solonoid, if it keeps dragging, have someone hold the key switch and you tap on it to see if it makes the starter improves.
Obviously check all the connections.
First and most important, after charging the batteries, do a load test on each one to see just how good they are. A regular voltmeter won't do it, something like this from Harbor Freight or the like will pay for itself after just a few uses and make you look smarter.

[bassarama]

Thanks guys

I have tested the batteries with a tool like that, both tested ok, I even try with my truck’s battery to double check…
Is the starter motor supposed to be resistant if one turns its gear by hand? Also, for the fact that it would not crank by turning the ignition key, I believe the starter motor and its solenoid could be the culprit. Tomorrow I’m going to investigate further, perhaps take the starter apart before ordering a new one. Thanks again for your help.

Joe

[THEFERMANATOR]

The starter should have some resistance when turning by hand from the armeture passing by the magnets. How fast does it spin up when you try to start it? And grease on the bendix like that can cause starter problems. It may not look like it, but there is a rubber clutch disc inside of that gold part with the teeth that contact the flywheel. If grease gets in there it won't turn the engine over because there won't be enough friction to engage it.

[spareparts]

use that load tester to check the battery cables, Hook it up at the starter solenoid and the block, when you load it, it will tell you how much you are loosing compared to straight at the batteries. I've found bad acbles, bad connections, and bad battery switches using a load tester. Yamaha's are particualry prone to having battery cables problems if they have the factory cables