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MANIC MECHANIC
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Discussion Starter #1
I finally got the bike legal went to ride it home today. After 10 miles at 65-70 mph I got off at my exit the bike stalled and I had no spark. all the lights worked the starter turned over but all it would do is flood and backfire. after sitting for 10 to 15 mins and some cranking with the petcock off. the bike started right up. could this be an igniter issue. this is the second time it has done this to me. any help would be appreciated.
 

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Could it be the Phantom Out of Gas Syndrome (POGS)?
 

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MANIC MECHANIC
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Discussion Starter #3
no dealt with that a couple of years ago gas cap vents straight to atmosphere it will flood if i keep cranking the backfires sound like gunshots i just have no spark.
 

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The Reanimater
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847 Posts
Sounds like your Float/Floats is/are sticking open and Your flooding out. Next time tap your carbs and see if it starts up faster.

I finally got the bike legal went to ride it home today. After 10 miles at 65-70 mph I got off at my exit the bike stalled and I had no spark. all the lights worked the starter turned over but all it would do is flood and backfire. after sitting for 10 to 15 mins and some cranking with the petcock off. the bike started right up. could this be an igniter issue. this is the second time it has done this to me. any help would be appreciated.
 

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MANIC MECHANIC
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943 Posts
Discussion Starter #5
its not a fuel issue I have no spark when it shuts down thats why it floods when i keep cranking it. anything will flood if there is no spark to burn whats coming in reason i believe igniter is that there is no spark in either cylinder. then after time to sit and cool down it fires right up. i cannot duplicate it in the garage it only does it after high speed crusing.
 

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The Reanimater
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NO Your Wrong.............

For gas to Ignite it has to be in a Gaseous form with the float sticking open it is letting as much fuel pour through when your slowing down as when your running fast. But when you slow down, too much fuel is coming through for it to ignite so it dies. So as you keep cranking more fuel is added, your still firing but it can't ignite because too much Liquid. As it sits the liquid drains and that's why it starts.

You need to check your oil and see if your level is up and if it smells like gas.


its not a fuel issue I have no spark when it shuts down thats why it floods when i keep cranking it. anything will flood if there is no spark to burn whats coming in reason i believe igniter is that there is no spark in either cylinder. then after time to sit and cool down it fires right up. i cannot duplicate it in the garage it only does it after high speed crusing.
 

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I agree with jt. A flooded carb will make it seem like there is no spark but when it back fires it is igniting the fuel. When it does this again pull a plug and if it is wet it is flooding out. If it is dry then you can check for spark.
 

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i think the ? needs asking to clarify, have you verified no spark? i think the assumption is that flooding is causing the lack of spark but if spark is absent first then flooding will follow. sounds to me like either the coils or igniter are getting hot and giving up till you let em cool down. usually a sign of impending failure in ignition electronics in any vehicle. just sayin. good luck with it.
 

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That's pretty much what i said. "When it does it again pull the plug to see if it is wet, but if it is dry then check for spark" That would be the best way to diagnose the problem when it happens. Were he can't get it to do this in the garage. That will let him know where to go from there, instead of troubleshooting a bunch of things.
 

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I agree Mitch. We need to verify if there's spark. VulcanJoe, I don't see what year your bike is, so this statement might not apply: This sounds like the hot start problem a lot of us have dealt with. I'm sure you have an MF battery in the bike, right? Of course you've been a member here longer than I so it is possible that you have an old MF battery that needs to be replaced. Again, I'm just thinking out loud... I'd check the battery voltage with the key OFF. If it is 12.5v then I'd check the coil wiring to see if you're getting a rather large drop off when the key is turned to ON. Check the red coil power wire with the key ON with each coil. If it is quite a bit lower, like 11v or so, then you have some weakened wiring going to your coils. You're probably doing these tests on a cold bike. Imagine when things get heated up good that the voltage would probably drop some. I'm not saying that this is your problem, but from what you described, it sure could be. Check out the coil wire mod in my sig. It's worth at least testing for, whether you decide to mod the wiring or not.

Either thing, weak spark, or too much fuel, gives you a rich condition, and can give you the "wake the dead" backfiring on trying to start the bike when its hot. The fact that you said after you waited 15 minutes or so, the bike started up, again sounds like it needed to cool a bit. Some claim that the r/r gets too hot and puts out lower voltage, which is why lots of us moved it out to the left passenger foot peg area. I did this and the coil wiring mod the same night and one or both of them solved my hot start/backfiring problem. It never did it again. Of course the coil wiring mod bypasses the r/r for coil power, and uses heavier gauge wire straight from the battery to the coil, via a relay, so more than likely, the coil wire mod did the trick. Just saying... something worth checking on.
 

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MANIC MECHANIC
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Discussion Starter #11
ok here is a little clarification i got home late last night and was tired
the bike is a 99
the carbs were just disassembled and cleaned 2 weeks ago by me same as every year
i also have inline fuel filters
i have a brand new exide sc30lfa maint free battery 445cca 28ah
brand new tim parrott stator
shindengen fho12aa mosfet r/r charging at 14.2v at idle
i already did your coil relay mod fergy except i used 10ga wire
pickup coils were gapped at .018 as suggested by lance328
i did verify with a new plug that i did not have any spark (yes i do carry a new set of plugs just in case
plug wires are new
the reason i am questioning the igniter is because i dont think the carbs would both be wrong it actually runs slightly lean right now and when i checked the float levels they were both 2-3mm over the bottom screw in the air cut valve on the bench.
the other thing that will give the wake the dead backfiring is the fuel getting into the blistering hot exhaust.
but the igniter seems to be the only common thread between both cylinders.
 

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MANIC MECHANIC
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943 Posts
Discussion Starter #12
the other thing is turning off the fuel at the petcock and cranking should clear a flooded condition that being said i still had no fire.
 

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The Reanimater
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Question: Was it doing this before you disassembled and cleaned your Carbs 2 weeks ago?

ok here is a little clarification i got home late last night and was tired
the bike is a 99
the carbs were just disassembled and cleaned 2 weeks ago by me same as every year
 

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MANIC MECHANIC
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943 Posts
Discussion Starter #14
dont know i put the bike away last september when the knocking noise from the dampers started getting worse. i just got it put back together a couple of days ago but it rode fine last year.
 

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The Reanimater
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847 Posts
Go to harbor Freight and pick up one of these: Sale: $4.99


Inline Ignition Spark Checker - Item # 4424
Then you can see for sure if your getting Spark/No Spark when you crank it. I'm thinking about get a few more and put one in each of my cars.

Also pick up one of these they work Great: Sale: $7.99

Flex Drive Compression Tester - Item # 92697
 

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MANIC MECHANIC
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943 Posts
Discussion Starter #16 (Edited)
I am a mechanic by trade I already have this set.

I used it I had no spark on either cylinder after running for a while today. same scenario around 10 miles on the highway i pulled off on a ramp when the idle went down it shut off. i turned off the petcock and tested the spark i had none but i came prepared i brought a book. after 20 mins it restarted no problems. I brought it back home I have never been afraid to go back and double check my work. i decided to check the float levels again the left one was right on 2mm above the screw the right one was 9mm so i need to do some more adjusting there. i will do that on wednesday. when i install the shims and new jets. another peculiar thing i decided to remove the air cut valves both had fuel on the vacuum side of the diaphram. is this normal i have power at the coils so that only leaves one thing I have bid on an igniter on ebay hopefully i will get it. another thing i noticed today when it is running the warmer it gets the lower the idle drops. if i were to go start the bike now it would idle about 2500 rpm as it gets warmer the idle goes down. it is kind of slow to return to idle i checked and readjusted the cables no slack on the close 1-3 mm on the open could the slow to return to idle be a symptom of a leaky air cut valve. although i can see no damage on either one. i have already smoke tested the boots they are ok.I used this

any ideas.
 

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The Reanimater
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Ok, It could be a Bad Solder Joint that open when it heats and closes when it cools.
Also I seem to remember here a few months back there was a rash of bad J/B Boxes/Fuse Boxes.....The wet batteries had leaked and Burned a hole through the back of the Box. You couldn't see it until you pulled it off.

I used it I had no spark on either cylinder after running for a while today. same scenario around 10 miles on the highway i pulled off on a ramp when the idle went down it shut off. i turned off the petcock and tested the spark i had none but i came prepared i brought a book. after 20 mins it restarted no problems.
any ideas.
 

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MANIC MECHANIC
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Discussion Starter #18
I ordered a new igniter from ebay when checking the carbs on the bike i found fuel behind the coasting enricher which might explain my slow return to idle. but i have since noticed a change in my charging voltage at first it was 14.2 at idle now it is barely 12.8 it is a new stator (tpe) shindengen fho12aa r/r connected straight to the battery with a fuse i find this disturbing. but the battery when tested with a snap-on microvat said it was good. so it must be charging. i just dont feel good about the change after 2 weeks.
 

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At idle, my bike was showing around 12-12.5 volts on a regular basis, then at 4000 rpms it was up around 13.8 volts. Usually, the bike is barely charging the battery at idle (~1100 rpms) so I wouldn't sweat it. IMO, I'd worry more if it was the other way around. Make sure it is jumping up to 13.8 or so when you rev it. If so, I believe that is the benchmark.
 

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MANIC MECHANIC
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Discussion Starter #20
it is climbing it 3-4k rpm and like i said i tested the battery with a microvat and it was ok i was talking to ron he thinks it bay be the size of my battery and now that it is charged doesent need the voltage. but i didnt manage to drag my lazy a$$ out of bed til 5 pm last night sick all day. so we will try on my next day off sunday.
 
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