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Discussion Starter #1
Okay all. I need some fresh insights. I have an ’89 vn750 with just under 26k “indicated” miles (speedo cable was broken when I bought it). Basically stock, with a new stator and upgraded mosfet r/r.

At the beginning of the year I was noticing some intermittent trouble starting her up. The starter motor would spin, but the engine would not turn over. After a few tries, it would kick in and start.

It was intermittent, so I didn’t do anything about it right away. Now it won’t start at all. The starter motor still spins, but the engine won’t engage and turn over. And I don’t know if this is directly related or a secondary problem, but I now have no spark on any plug. Should I have spark if the engine doesn’t turn over? I’m thinking yes, but could be wrong.

I have a Clymer manual and have checked the following:
Battery (AGM, but may be getting old)
Fuses
Starter relay
Starter motor (just rebuilt last summer and still checks good)
Pick up coils
Ignition coils
Igniter
Spark plugs & wires (all new last summer)
Neutral switch
Side stand switch was removed by PO

I don’t know about the JB itself or the starter clutch. Any thoughts? Thanks for your help. I’m missing a lot of good riding weather. Grrrr.

John
 

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First off im not at home so I cant referance my manual, But im almost positive you will NOT have any spark if the engine does not turn over. The pick-ups inside the left hand cover cant induce voltage to cause a spark, has to do with the timing im sure.
As for the starter issue, it sounds to me the starter is bad. Seems like the solenoid is not kicking out the starter gear to engage the engine. I wonder if u could remove the starter and see if the gear kicks out with the starter button pushed. Not sure if it needs to be grounded but I think it would be. Plus it has some torque im sure and would have to be held firmly. Lets see if someone else agrees with me. Or has a better idea. You might even be able to take it to an autoparts store and they could test it for you.
 

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romeobravo172
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Sounds like starter is spinning but not engaging to turn the motor, no motor turn no spark.
 

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First off im not at home so I cant referance my manual, But im almost positive you will NOT have any spark if the engine does not turn over. The pick-ups inside the left hand cover cant induce voltage to cause a spark, has to do with the timing im sure.
I support this info. No spark.

Sounds like starter is spinning but not engaging to turn the motor, no motor turn no spark.
I'm not sure the VN750 starter has a starter solenoid like a car. I think the starter motor stays engaged to an idler gear or starter clutch. There could be something inside the case that is not right.

~~C8>
 

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Sparky!!!
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I'm not sure the VN750 starter has a starter solenoid like a car. I think the starter motor stays engaged to an idler gear or starter clutch. There could be something inside the case that is not right.
you are correct...

remove the starter and inspect the starter clutch and drive gears.
 

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Linkmeister Supreme
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X2^^^^^ I agree with slim.
 

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Discussion Starter #7
Thanks guys for your input. Sometimes you're just so close to a situation you can't see the forest for the trees.

I removed the starter motor. The opening is pretty small and I can only see the bottom of one gear (not sure which one it is by name). Don't see anything obviously wrong with it (chipped teeth, etc.), but it moves freely in both directions. Should I not encounter resistance in one direction?

To really see the rest, it looks like I'll have to remove the right side case cover. Is this correct? And if so, can I do this without pulling the engine as the manual says? Just support the front with a jack and remove the right side frame member, then unbolt the case cover?

Sorry for all the questions, but I'm heading into new territory here. Thanks again.
 

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try the starter manually with booster cables if you can to make sure it is spinning out to engage. now i don't know much about these starters but that was how i used to check others staters
 

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Sparky!!!
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read chapter 15-26 in the Kawasaki Service Manual... Pay special attention to subsection titled "Starter Clutch Inspection" which is found on pdf page 280. I hope this helps you out some.
 

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Discussion Starter #11 (Edited)
Okay, I'm attempting to remove the right hand crank case cover while the engine is installed. The right sub-frame is out and I've removed 13 bolts from the perimeter of the cover. There are 2 bolts kinda in the middle of the cover. Is it necessary to remove them? And if so, are they holding anything more than just the cover? I don't want to take them out and remove the cover only to have loose parts fall out not knowing how they go back together. Any thoughts?

John

EDIT: Never mind. I think I answered my own question. Preparing to remove side cover.
 

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Discussion Starter #13
Well, the cover is off and an inspection of the gears finds no obvious damage at all.

The problem: The bolt holding the starter gear in place was loose allowing the idler gear to spin, but not engage the starter gear (thus the 2-way free movement I noticed earlier). So this is an easy fix by all appearances. Tighten the bolt to specs and put it all back together.

Last question: Have you ever heard of these bolts just coming loose like that? Is that something I'll have to worry about possibly happening again?

Thanks again to everyone who was able to respond.

John
 

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Discussion Starter #16
I should have known...nothing is EVER easy!

Tightened the bolt with applied blue loctite. Starter gear is now engaging and the engine intermittently tries to turn over, but sometimes the starter gear just spins. I made sure it free spins one way and not the other.

The book suggests that when the engine won't crank, other possibilities could be problems with pistons, crankshaft bearings, connecting rod, transmission or clutch.

I'm at a complete loss now. What would be a best guess at the most likely culprit here?

John
 

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^ x2 ^

~~C8>
 

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Discussion Starter #20
Here are some pics. These are two parts, don't let it come apart. I am not sure if it is timed, but make sure it goes in just as the other one comes off.

I read (and observed on my bike) that the balancer has an index mark that must line up with an index mark on the shaft when installed. Not sure if there is any particular alignment with the starter gear. The manual just says to "Push the gear on until it bottoms out."

What I don't understand is when the starter gear and beveled washer are installed and the shaft bolt is torqued down, it seems that there is still some lateral play with the starter gear. Is it designed that way or is it a symptom of the problem?

As for rotation, it free spins one way and not the other...as it should. Yet, when voltage is applied through the starter motor it still doesn't engage the engine as it should.

John
 
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