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  #11  
Old 12-23-2016, 05:14 PM
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sbest sbest is offline
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Default Re: Engine won't start.

There is a mechanical maintenance trouble shooting principle of putting everything back to the "as designed" state to start the troubleshooting process. The next principle is to look to see if you have everything you need to make it go. Fuel, air, compression, spark, and timing.

So, first of all, fix all the little problems, loose bolts, missing parts. Then:
1) Fuel, pull the fuel line off at the carb and drain some fuel into a glass jar.
- does it flow well? Is it clean?, Does it have water in it?
- Is the carb level? Leak free?
- Did you set the float level? A nipple to the drain with clear line is the best gauge.
2) Air, is the air filter clean and clear? Is the carb and intake well sealed? Exhaust clear?
- Crank seals and gaskets? I do a 4-7psi leak test to check these.
3) Compression, over 110psi?
4) Spark bright yellow and audible "click"? Clean or new plug, right type?
5) Timing not changed from when it ran? Did you have it apart? 1 o'clock at TDC?

By checking the clean plug you will know if it is flooded or not getting fuel.

The answer is in there somewhere...

Steve
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  #12  
Old 12-23-2016, 05:17 PM
DarkWolf2k DarkWolf2k is offline
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Default Re: Engine won't start.

Got the carb bowl gasket fixed so that's all good. Thinking I'll probably run it with the spark plug out now and then let it have some more gas and do it again a time or two to run out any possible water in the engine.


@StevenMain Should I still adjust the float if it doesn't have gas coming out of the air filter with the petcock open?
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  #13  
Old 12-23-2016, 05:47 PM
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Default Re: Engine won't start.

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Originally Posted by DarkWolf2k View Post
Got the carb bowl gasket fixed so that's all good. Thinking I'll probably run it with the spark plug out now and then let it have some more gas and do it again a time or two to run out any possible water in the engine.

@StevenMain Should I still adjust the float if it doesn't have gas coming out of the air filter with the petcock open?
Gas running out of the carb is a stuck needle valve. Needs to be cleaned.
Float level check is one of the primary carb checks.
Cleaning and float level check is first thing you do with carb problems.

Steve Best
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  #14  
Old 12-23-2016, 06:17 PM
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Agreen Agreen is offline
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Default Re: Engine won't start.

If fuel is not coming out of the air filter, then it probably isn't a float issue. It's a common issue, but probably not your problem.

If you (or your friend ) let it sit outside and it had water in the magneto cover, open it back up and hose it down with WD-40. The WD stands for "water drying". No, seriously. You could also disconnect the kill switch if that doesn't work, since it creates a short when pressed, but could have water in it.... causing a short.

But most importantly, do what sbest has said. It's a good troubleshooting guide to follow.
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  #15  
Old 12-23-2016, 06:18 PM
DarkWolf2k DarkWolf2k is offline
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Default Re: Engine won't start.

Quote:
Originally Posted by sbest View Post
Gas running out of the carb is a stuck needle valve. Needs to be cleaned.
Float level check is one of the primary carb checks.
Cleaning and float level check is first thing you do with carb problems.

Steve Best
The carb bowl gasket wasn't seated properly when it was shipped. After fixing this I have no more gas leaks as far as I can tell. It might have had something to do with my friend trying to re-seat the gasket as there was a significant amount of debris in the float bowl. I cleaned this and checked the main jet? I guess it's called. To make sure gas flowed out. I probably skipped a lot of steps I would have done on one that I owned but my friend isn't exactly friendly with how he treats his bike.
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  #16  
Old 12-23-2016, 06:22 PM
DarkWolf2k DarkWolf2k is offline
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Default Re: Engine won't start.

After a lot of headaches of trying to figure it out, doing routine maintenance stuff like tightening down loose bolts, etc. I got it to run just fine. Turns out the clutch was slipping quite a bit. I didn't adjust the float at all cause no fuel was coming out of the air filter. I did take Steven's advice though and took the spark plug out and ran it without for a bit to unflood it I guess? I dunno if it helped but it's running so hooray. Thank you everyone for your replies.
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  #17  
Old 12-23-2016, 10:38 PM
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Default Re: Engine won't start.

If I had to guess, I'd say it flooded when you had no spark from the magneto being wet. Once it dried out, the case was probably full of fuel, and blowing it out solved it.

Good work!
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  #18  
Old 12-27-2016, 10:48 PM
DarkWolf2k DarkWolf2k is offline
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Default Re: Engine won't start.

Quote:
Originally Posted by Agreen View Post
If I had to guess, I'd say it flooded when you had no spark from the magneto being wet. Once it dried out, the case was probably full of fuel, and blowing it out solved it.

Good work!
Had it running for a few days and it would bog if I let the fuel on before starting it. Once starting/running with fuel off and I could turn the gas on and it would act completely normal. Now it will start whether fuel is on or off and seems to completely bog unless you're pedaling about as fast as midway throttle to as fast as you can possibly pedal. Then it'll sputter a bit at mid-high range, produce some power, and eventually die. I've done a complete breakdown and rework from the gas tank to the intake on the engine. Checked gas tank, petcock, fuel lines, in line fuel filter, carb reassembled. Checked gas before putting it in the tank and all seems okay. Nice blue tint and no particles.
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  #19  
Old 12-27-2016, 10:50 PM
DarkWolf2k DarkWolf2k is offline
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Default Re: Engine won't start.

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Originally Posted by DarkWolf2k View Post
Had it running for a few days and it would bog if I let the fuel on before starting it. Once starting/running with fuel off and I could turn the gas on and it would act completely normal. Now it will start whether fuel is on or off and seems to completely bog unless you're pedaling about as fast as midway throttle to as fast as you can possibly pedal. Then it'll sputter a bit at mid-high range, produce some power, and eventually die. I've done a complete breakdown and rework from the gas tank to the intake on the engine. Checked gas tank, petcock, fuel lines, in line fuel filter, carb reassembled. Checked gas before putting it in the tank and all seems okay. Nice blue tint and no particles.
Also; if you start and run it with gas off and continue pedaling it will eventually stop sputtering and just bog completely. It seems like a gas problem like it's starving but everything I've checked seems fine. The carb is just slightly off level.
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  #20  
Old 12-27-2016, 11:15 PM
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Agreen Agreen is offline
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Default Re: Engine won't start.

Terminology time:

4 stroking - when the engine is "sputtering" or has that "machine gun" feel. Due to having too much fuel (rich)

Bogging - A notable drop in power, without any other strange noises. Sounds like (and feels like) the engine is just spinning down and not producing power. This is due to a lean condition (too little fuel)

Now, the situation you described above with turning off the fuel sounds like it is just normally running too rich. Once the bowl starts to empty, you start to experience a short moment of correct air/fuel mixture and it runs good for a second, then runs out of fuel and bogs entirely.

That could mean a couple things. One possibility is that you are running your oil mix too thin. More oil per part of gas makes the air/fuel mixture more lean. Less oil means a more rich condition. You're experiencing a "too rich" condition, so try a higher oil/fuel ratio? What is yours currently, and how do you mix it?

Another cause can be the needle. It's connected to the carburetor slide with an "e-clip". Move the clip up to go lean, but this only adjusts air/fuel mixture up to about 3/4 throttle.

If changing your gas/oil mix and moving the needle doesn't help, I'll step you through re-jetting the carb.
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Last edited by Agreen; 12-27-2016 at 11:17 PM.
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