BN Wont Fire

jeffred · May 27, 2013

I have a 12 volt BN that I am having troubles getting to fire. I replaced the spark plugs last week (Autolite 3116) and it fired up after a few tries. I went out to start it a couple days later and the engine would crank, but it would not fire. I tried until I ran the battery down a couple times with no success in firing. This afternoon I went out and tried a third time and still I had no luck. I am very lost right now and very disappointed. When I first got this tractor last fall, it fired up each time with no problem. Since then it has progressively gotten more difficult to start and now it wont fire at all. I am baffled.

I am trying to figure out what to do next. The carb is leaking from the choke valve, the drain screw, and the hose between the air cleaner and the carb. The front plate on the starter gets very warm after I try to turn it over. Where do I go from here, new wiring harness/battery cables, new carb, new battery etc??

Thank you for your time. If you are a vet--thanks for your service!!

Anonymous-0 · May 27, 2013

Check to make sure your points are opening

jkmdg84 · May 27, 2013

Which points are you referring to? Thanks

ken house · May 27, 2013

you say wont fire, i suspect you mean will not run. cut gas completely off at tank, you are having a flooding problem. let it sit for 30 min or so, come back open gas valve and about 10 secs. close it. try to crank and see if it will hit.

solder a wire to a spark plug, not on tractor, to the base and put an alligator clip on the opposite end of wire. remove wire from sparkplug on tractor and put on the spark plug with wire attached, clip alligator to metal on tractor. crank tractor and check to see if plug is firing.

if not firing you have a wiring problem.

Red Dave · May 27, 2013

"The carb is leaking from the choke valve, the drain screw, and the hose between the air cleaner and the carb."

Sounds like the carburetor is flooding. It also sounds like the needle valve in the carburetor is sticking open.

Clean out the carburetor, make sure the needle and seat are closing, make sure the float is set to specs.

old · May 27, 2013

Trouble shooting 101
Spark at all 4 plug wires needs to be a blue/white and jump a 1/4 inch gap. If no spark the distributor or mag points which ever you have may need cleaned or replaced.
#2 check for a good steady flow of gas out the carb drain plug. Catch it so as to look at it for water/dirt etc.
#3 when was the last time you serviced the oil bath air cleaner.
Post back what you find

CharlieNJ · May 27, 2013

He is referring to the "ignition points", be it a magneto or battery ignition. Ignition points need to open and spark, AND they need to close electrically. So if the points are set too wide they may not close to let the coil charge, and there will be no spark, if the points are dirty, they will not "close" electrically, and you get no spark, if they do not open, then you would also get no spark. You might just have dirty points. Clean them up with some 400 grit dry paper. Better yet, replace them, and set them properly.

BN Wont Fire

jeffred

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Anonymous-0

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jkmdg84

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ken house

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Red Dave

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old

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CharlieNJ

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