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"ya can't live forever"
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321 Posts
Discussion Starter #1
Ok here goes 1998 VN750 21k miles. New stator, new R/R, new wire harness
and new plugs. Carbs removed and cleaned.......Will not start !!! Ran before
stator replacement. Cranks strong w/mf battery. Spark from the plugs is not
fat blue spark one would expect. Prior to all the work being done plugs in the
front cyl. were sooty black and could not keep bike at idle. Gas tank has been
drained and cleaned along with the petcock.
Before I head to the HD dealer ( not really !) I will put the question to you
as to what I should do next....really losing patience:BLAM: TIA
 

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Premium Member
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Sounds like somewhere in the wire harness replacement, something didn't get hooked up correctly or isn't making good contact. Possibly at the IC ignitor module or at the coils. Might be a dirty ground somewhere in the ignition wiring as well. I'd work backwards from the coils and trace it down that way. If it ran before, it has to be something that happened during the electrical equipment replacement. My .02.
 

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"ya can't live forever"
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321 Posts
Discussion Starter #3
I've been thinking the coils may be the cause. Could have the red and green wires misplaced on them. The manual does not indicate the terminals for red and green.
 

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Could be. If the spark is weak, that might be a good place to start.
 

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"ya can't live forever"
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Discussion Starter #5
Yeah brother it's extremely disappointing to have put this much work into the bike and get these results.
 

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I had to take mine in to a mech after I rebuilt the engine because it wouldn't start. Turned out that somewhere during the engine reinstall in the frame, the carbs got bumped out of their boots just enough to stop the engine from running. A casual inspection didn't reveal the problem so I had no idea. The mechs fumbled around for about 4 hours before discovering the problem. Fortunatly they only billed me for 2 hours. At $70/hour, it was still expensive. It was a simple problem but it took a fresh set of eyes on it to find. Your possible crossed wires on the coil are probably on the right track.
 

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"ya can't live forever"
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321 Posts
Discussion Starter #7
My God those boots are a PITA. After I figure out this problem those ears are
the next project.
 

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Geek
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Also, is there gas in the carbs ?
 

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Once Banned
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2,125 Posts
Does it backfire? Could be the flywheel thingy with the magnets on it, or the pickup coils are reversed.

Looking at the wiring diagram, one of the coils gets red and green, the other gets black and green. It doesn't matter which terminal on the coil gets red or green, or which terminal gets black or green.
 

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sounds like coils to me. are they backwards?
 

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Search Goddess
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Pickup coils are not to be confused with the coils that the spark plug wires run from.
If it were the pick-up coils (located behind the round stator cover) being reversed the bike would produce a loud THUNK on start-up because your timing is off 270 and 90 degrees. (that's right.. not 180 on both but 270 and 90)
If the pick-up coils are reversed the bike goes.. crank, crank, crank, THUNK!
Sounds like something slammed into something inside the engine.

Now as far as the spark plug wires and related coils.. I didn't think there was a right or wrong side since they are CDI base but I could be wrong. I have never had to mess with mine. You should be able to perform a resistence test on the secondary coil between the two spark plug leads. (check both coils)

Another suspect though might be the IC Ignitor. This is located behind the battery.
Pick-up coils send a signal to the Ignitor which sends the on/off signal to the coils and produces the current to fire the spark plugs.
There is also a resistence test you can to on the ignitor.
The chart for the resistor tests should be in either the online Kawasaki Service Manual or Chapter 8 of the Clymers manual if you have them.
 

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Once Banned
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Forgot about the thunk. I've never experienced that, so I don't know, but from what Dianna said, it's not an issue with pickup coils or spark plug coils being reversed. The IC igniter is what controls the timing of the spark, so that is a possibility. But, I find it hard to believe it would go bad just sitting there. I'm sure it IS related to something you disconnected/reconnected. Clean the connectors going to the IC real well.

Also, it could be your engine ground. Disconnect the ground from the battery to the engine, clean it, and ohm it out.

Other than that, no more thoughts for now. Make sure you follow what Dianna said about the resistance checks.
 

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"ya can't live forever"
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321 Posts
Discussion Starter #14 (Edited)
RE: No START

Alright folks here is the update. What Diana stated is true....it does not matter how the wires are connected to the coils. ....No thunk from the stator
everything is turning freely......However that stupid hose
that vents the carburetors was pinched.....freed it up and the motor
started right up:doh: . Ran ol' Tatonka down the hwy and ran well in first and
second......third and higher had considerable missing and break down.

I will adjust the pilot screws and see if a richer mixture fixes the problem.
Will keep you all posted, thank you for all the input.:smiley_th
 

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Geek
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If your talking about the air fuel mix screws, they won't help.
 

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They are for idle and low speed only. High speed is taken care of by the internal jets.
 

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I don't think so. Sounds like your coils are fine. If you are sputtering at higher rpms, it sounds like fuel delivery. could be your main jets are clogged, not likely though. I'd check fuel flow from the tank through petcock. Did you add inline filters? Are your fuel lines bent narrowing the passages? Air vent in fuel tank lid clogged? Just some things to check.
 

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"ya can't live forever"
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Discussion Starter #20
Fergy, I am really inclined to believe there is an intake leak or that there is too much air entering the carbs at higher speeds. Thats why I thought the pilot adjustment would be in play. We'll see. Thanks
 
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