BN Starting Problems

jeffred · May 13, 2013

I have a BN that has recently began to have some seriously trouble firing. The engine will turn over just fine but it will not fire. I don't try to choke it at all. After several attempts it will randomly fire off. When it does fire, some smoke billows out from the exhaust pipe and from underneath the hood above the manifold. There is black soot around the hole in the hood where the exhaust pipe is held that seems to build back up after a few times cleaning it.

The carb does leak a little fuel. I have seen drips come from the choke valve, the drain valve, and from the rubber hosing that is connected to the air cleaner. I was wondering what some of you folks think--would it be the carb causing my starting troubles? If so, where would be the best place to buy a rebuild kit with good diagrams on how to put it back together? Could it be the spark plugs?

Appreciate the assistance!

old · May 13, 2013

As with any engine you check spark and make sure it is a good blue/white and will jump a 1/4 inch gap. Then you check fuel flow by pulling the carb drain plug and let it flow a few minutes. Catch it so as to look for water and dirt etc. Also make sure you air cleaner is not stopped up or full of water

gene bender · May 13, 2013

Another check is take the cap off and see if the rotor is lined up with the tower when it fores in talkjing about the mag as it fires on TDC if the rotor is off one tooth it does make a difference.

mkirsch · May 13, 2013

Leaky carb, lots of black soot... Sounds like the float is stuck open to me.

Time to tear it down clean it up and put in some new parts.

Unfortunately there is no kit with full diagrams. Back in the day someone showed you how to rebuild the carb. It's not complicated, though. Take pictures as you go if you feel you can't remember how it goes back together.

Tom Fleming · May 14, 2013

Also check to see if the air cleaner is plugged. Take the hose off between the air cleaner and the carb, and try to start again.

jeffred · May 14, 2013

What would be the recommendation for good spark plugs? I know that there are "spark plugs" and then there are good spark plugs.

teddy52food · May 14, 2013

Are you shutting off the gas valve under the tank. You may have a leaky needle & seat.

old · May 14, 2013

Years ago I used the champion brand but now days I use the auto lite plugs due to being better with the crap gas we now have. Off the top of my head I can not tell you the number of the plug and to do so I would have to go out and see what I have in my BA

Matt E. · May 14, 2013

autolite 3116s is the right plug if you have a mag. That's what I have in my B. Runs great after taking out the Champions

BN Starting Problems

jeffred

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old

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gene bender

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mkirsch

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Tom Fleming

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jeffred

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teddy52food

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old

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Matt E.

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