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Discussion Starter #1
I have been trying to crank my bike for weeks now. I finally got some seafoam and cycled through the carbs and still it won't crank.

The battery is a marine battery that is in good shape. I am getting fire but apparently it isn't firing enough or isn't under compression. It is spitting but nothing close to running, not even trying.

Any ideas to look at?

Grace!
Richard
 

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Check for a stuck float....that will cause starting issues for sure...getting any backfires ?

Fuel + air + fire....thats whats needed as a basic...if any are lacking, or TOO much, will cause issues...also, if a float is stuck, and it floods the cyl, even a decent battery might not push it over enough....

Try putting a charger to the battery, at like mebbe 10 amp....wait 3 mins and with still connected, try it....if it starts right up, then prolly a stuck float...
 

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What is that battery's cold cranking amps rated at? And any idea how many volts it is putting out while you are trying to crank it?
 

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Discussion Starter #4
I will check the voltages tomorrow. Good to see someone that is close to me with the same bike. I saw the Fl. Gator and thought Jacksonville but St. Augustine is close too.

Grace!
Richard
 

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There's actually a couple of other guys on here in Jax too. Chris32250 is out at the beach and ifixf18s is in Jax I think. Where are you located?
 

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Discussion Starter #6
Brunswick, Ga. about 45 miles from the state line. It is still a little way to you but a whole lot closer than some of the guys in the Honda forum I used to be in.

Grace
 

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Discussion Starter #7
Wolfie, I just pulled the carbs and cleaned them thoroughly but I am not seeing any gas on the plugs. However this afternoon I pulled the plug that is exposed and not the one that is down inside (didn't have the right socket here). Tomorrow I will test that.

I posted somewhere else that the exposed plug when removed is blowing my finger off hard and not sucking my finger in which made me believe that the spark plugs were not redundant and I needed to check the other spark plug to see if it is getting wet.

Grace!
 

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Doesn't sound like there's enough fuel getting to the cylinders. Have you tried applying vacuum to the center port of the petcock? Assuming you don't have the early model without the vacuum line. That would fill the carbs if the floats are opening.

I used starting fluid on mine one time, the others I just put vacuum on the port.

Need to get some fuel in there.
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They are redundant. Not only do both plugs fire together, the VN is waste spark. It fires at the top of compression and exhaust stroke.

The reason for 2 plugs per cylinder is so it can run more compression w/o detonation. Max advance is 25*. Most OBD autos will run more than that at no load idle once in closed loop.
 

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Discussion Starter #10
You know I am not sure if I got anything hooked up right when it comes to the vacuum lines. When I got the bike all of that was disconnected. I may have all that wrong and that is why it isn't getting any gas. I now on the left side of the bike if I was sitting on it, there is a hose coming off the nipple of the carb on that side that goes up to the center nipple on the gas tank.

On the right side I am not sure I know where that goes from the nipple from the right carb. And in between the carbs that line isn't hooked up to anything.

Some help would probably find it beneficial it hooking those up correctly.

Grace!
Richard
 

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Have a look at this thread and the pics I posted in it and let us know if you need more info.
http://www.vn750.com/forum/showthread.php?t=31633

You are correct about the vacuum line running to the center port of the petcock, the vac line off the other carb runs to the suction valve for the reeds.

Then there are two fuel lines, one in the front and rear. In the center should be a Tee that is the carb vent, the single line from the tee runs to the right ear. Just check the pics and let us know.

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Discussion Starter #12
Ok everything is hooked up correctly unless the vent tubes in the middle are bent to blocking air flow as I realized after installing the carbs I had put the vent tubing assembly back on backwards and didn't really want to pull the carbs again.

But it may look like I need to pull the carbs again because of no gas flow.

Grace!
Richard
 

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As long as they aren't kinked and closed off. The end that goes into the holder in the ear is supposed to be cut at a 45° angle to keep it from getting blocked off against the ear.
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Discussion Starter #14
Found a issue, actually two.

First my gas lines were kinked and I didn't know it. The front hose was kinked bad and the rear one was better but still slow. I will fix that.

The front cylinder is giving off a good spark but the rear one is very faint. Both sides of the rear coil/plug is about the size of a hair and orange. I figured with the front cylinder getting little gas and the rear cylinder getting little fire that my bike isn't cranking.

Now the front cylinder rubber boot around the carb cylinder side is puff every once in a while smoke. So it is firing but not going through the exhaust just puffing the smoke around the carb boot. Nothing around the rear cylinder.

Can the coil be tested. Can something else cause the coil to not fire correctly or with the amount of spark that it needs? I am going to clean the leads to the coil and see if that is the cause to the poor spark. Hopefully I won't have to purchase another coil.

Grace and Blessings!
Richard
 

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Found a issue, actually two.

First my gas lines were kinked and I didn't know it. The front hose was kinked bad and the rear one was better but still slow. I will fix that.

The front cylinder is giving off a good spark but the rear one is very faint. Both sides of the rear coil/plug is about the size of a hair and orange. I figured with the front cylinder getting little gas and the rear cylinder getting little fire that my bike isn't cranking.

Now the front cylinder rubber boot around the carb cylinder side is puff every once in a while smoke. So it is firing but not going through the exhaust just puffing the smoke around the carb boot. Nothing around the rear cylinder.

Can the coil be tested. Can something else cause the coil to not fire correctly or with the amount of spark that it needs? I am going to clean the leads to the coil and see if that is the cause to the poor spark. Hopefully I won't have to purchase another coil.

Grace and Blessings!
Richard
Your coils have +12V on one lead and the negative lead is pulsed from the Ignitor Box. Ensure your Ignitor box grounds are clean. Suggest you perform the "Coil Mod"...it will supply full battery voltage (at all times with ign key on) to the coils for great spark, thus avoiding voltage drop/reduced thru old wiring harness. Also note, while cranking with the starter, if you have less than 12 Volts at the coils, your spark will be very weak. With starting issues (constant battery drain) attaching a booster battery is suggested.

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Now the front cylinder rubber boot around the carb cylinder side is puff every once in a while smoke. So it is firing but not going through the exhaust just puffing the smoke around the carb boot
That boot is leaking, it needs loosened, reset, and tightened again. Major source of starting/driveability problems, a vacuum leak.
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