'41 'B' won't start by hand cranking

Stan - Florida

Well-known Member
I know this problem has been discussed before, but I'd like to get some advice. My brother has a '41 'B' that will not start by hand cranking. Pull-start it and it takes right off after being pulled just a few feet and then runs like a top. Seems to have good spark at the end of the plug wires.

Any help will be greatly appreciated.

Stan
 
Stan, one possible, among MANY causes of what you describe is a Magneto with a weak impulse spring i.e. a weak spark when hand cranking. When pulled fast enough for starting the impulse spring wind and trip mechanism is out of the picture. For good hand starts the static start timing needs to be right at TDC. If too fast she kicks back if too slow hard to start. Of course the points and condenser need to be near perfect condition. Good clean dry Autolite 3077 side wire deep reach hotter plugs is my choice.

Many start different, but mine (1938 B) likes the throttle to be back at slow idle position,,,,,,,,timing at TDC,,,,,,,,about 7/8 choke (Do NOT overchoke and flood). When shutting down if you turn the gas off and let it die from starvation then open the throttle wide open while setting seems to help mine. I always start mine on the Left cylinder such that the right is set to fire 180 later versus starting the on the right cylinder when its 540 degrees before the left fires.

See you next January I hope

PS I may be selling my 1938 B and if so I will post on You Tube my method where she usually starts the very first 1/4 turn pull over.

John T
 
You might consider checking the timing on the No. 1 (flywheel side) cylinder.

<font color="#ff0000">[b:654c4848f0][i:654c4848f0]To prevent the tractor from accidentally starting:
Remove the spark plug cable from the No. 2 spark plug.
Make sure the gas is turned off.
Tractor should be in neutral and the hand clutch should be disengaged.
If the tractor is in neutral, then lock both brakes.[/i:654c4848f0][/b:654c4848f0]</font>

This is one method of checking the timing for this No. 1 cylinder.

Remove the spark plug on the flywheel side.

Place your finger over the hole and rotate the flywheel in the running direction (counter-clockwise) until you feel pressure (compression) of air in the cylinder.

Continue rotating the flywheel counter-clockwise slowly until the “[b:654c4848f0][i:654c4848f0]L. H. IMPULSE[/i:654c4848f0][/b:654c4848f0]” mark on the flywheel lines up with the reference mark on the gear cover.

a197555.jpg" width="650"


Loosen the two cap screws securing the magneto.

Tap the top of the magneto toward the rear of the tractor a little at a time until the impulse trips.

Tighten the cap screws and continue rotating the flywheel counter-clockwise until you see a spark at full pressure (compression) for No. 1 cylinder.

Hope this helps.
 
Would believe your PROBLEM is in the MAG , just like you, someone JERKS you you kind of move fast but on your own that first step is at your will.
 
Usual cause of this problem is the impulse spring in the magneto drive end.
Either installed wrong (without pre-load) or broken.
 
Another thing, when my Wico X Mag was rebuilt a so called "hot coil" was used plus (if I recall correct) instead of a 1 inch, a 7/8 inch spring bushing was used which allowed 1 1/2 versus only 1 turn of impulse spring pre load tension which gives a strong loud SNAP and a good start impulse spark for better hand starts.

John T
a197574.jpg
 
John,

Thanks for the reply and the suggestions. I'll pass them on to my brother. He's closer to you than I am - he lives just west of Anderson.
 
James,

Thanks for the reply and the detailed directions. I think that's how we timed it 20+ years ago when I first got the tractor. It's now 1100 +/- miles away but I'll pass this on to my brother.

Stan
 

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