Farmall B magneto timing?

[Ken]

My Farmall B Ser# M214726G has a problem with the magneto .
Engine started to run rough then has quit. Taking the center coil wire off has a good blue spark and no spark to the wires to plugs. removing the cap the screws holding the gear in alignment had came loose and now it is out of time. My Question is how is the engine timed cannot locate a timing mark on the flywheel have removed the starter the oval inspection plate on bottom rear of transmission.and the round snap in plug on side. Also cannot locate a timing mark on front pully. Removing the valve cover can get close to #1 cyl. and piston at top center but need to locate 20 deg. before TDC.
Will be able to remove and replace mag. but need to get to proper timing first.
thanks ken

 

[Soundguy]

I don't own one of those.. however can help you with geometery... if you can locate tdc using a depth gauge, and decide when it stops moving, mark a line on the front pully at the top of the pully.. the rest is easy.. it's a circle.. and they have 360'.. grab a straight edge, a ruller and a compas.. find the center of the pulley nut.. now make a 20' angle using the center of the nut and the top mark as your guide.. the other mark you will make on the 'before' side.

that should give you a 20 degree btdc mark / reference.

Now.. you can mark your flywheel using a pin punch or china marker.. etc.

soundguy

 

[Ken]

Thanks for reminding me of this method. been a long time since needing this information.
Will do as suggested as soon it is daylight.
May have to remove the radiator to get to the front pully but better than getting kicked by the crank.
Will let you know the results tomorrow.
ken

 

[scott_vt]

My Farmall B Ser# M214726G has a problem with the magneto .
Engine started to run rough then has quit. Taking the center coil wire off has a good blue spark and no spark to the wires to plugs. removing the cap the screws holding the gear in alignment had came loose and now it is out of time. My Question is how is the engine timed cannot locate a timing mark on the flywheel have removed the starter the oval inspection plate on bottom rear of transmission.and the round snap in plug on side. Also cannot locate a timing mark on front pully. Removing the valve cover can get close to #1 cyl. and piston at top center but need to locate 20 deg. before TDC.
Will be able to remove and replace mag. but need to get to proper timing first.
thanks ken

Good Morning Ken,
To start with there are no timing marks on the front pulley ! When I rebuilt my Super A I filed a groove in the pulley when I reinstalled it on the crank, but from the factory there is no mark ! The best wat to get the engine in TDC is take out the #1 plug. Have some one crank the motor over slowly while you have your finger in the #1 plug hole. As the engine starts to come up on the compression stroke your finger will feel the pressure trying to push it out ! At this time you need to take the half moon cover right behind the oil pan off and carefully look in the flywheel for a very faint line that is scribed onto the circumference and is stamped DC. When that line, lines up with the pointer on the half moon cover your engine is on TDC. At that point your mag rotor should be pointing to your #1 plug wire. That line on the flywheel is hard to find, so you will need a wire brush and a good light.

You also stated that you had spark to the mag but none to the plugs. My best guess is that your points are not opening. These need to be clean and gapped at .013 ! I have two of these tractors and would be gladd to help any more if I can. Hopefully I have you started in the right direction !

 

[Soundguy]

Would love to see pics of your tractors Scott and ken.

The only IH i have is a cub, and it has the battery ignition.

I cam this close ( holding finger and thumb together ) to getting a good running/working/on the job 49 H with a 6' belly mower for a good price.. but passed it up before I knew what i was doing.. I regret it to this day.

ken, scott of course has given you the correct procedure which will be easier to implement than my generic advice. good luck on the machine!

Soundguy

 

[scott_vt]

Would love to see pics of your tractors Scott and ken.


Soundguy

Now Chris,
You know darn well that you have seen my tractors plastered all over TBN ! I know your pulling my leg !

Ken,
Another thing. After you have found TDC mark your flywheel with a white marker so its easy to find the next time. Also I didnt give you the procedure to actually time the mag. Loosen your mag up just enough so that you can just move it by hand and push the top of the mag towards the block. Now crank the engine over through the whole cycle until your on TDC again, at that point carefully rotate the mag away from the block ever so slowly until you hear the impulse coupling release. Stop right there and retighten the mag. The rotor at that point should be pointing towards the #1 plug wire. If its not then you got yourself monkeying around with those internal mag gears and they will need to be readjusted ! Also I dont know what your talking about 20 degs BTDC, the engine is timed at TDC period. Hope this helps !

BTW I also can tell you the proper procedure of adjusting your valves if you need to do that also !

 

[Ken]

Thanks for the information. soundguy and Scott.
unable to locate a scribe mark on the flywheel so cleaned with pressure washer and then solvent on a stick around the area think should be then was called away so tomorrow will try again.
scott the 20 deg. before TDC was to set mag in time before the impulse coupling is snaped for the spark at TDC will set as suggested when find the line.
se'ya ken

 

[Ken]

O'k Now have the Farmall B running the magneto had a weak condenser but the problem was the wire going to points through the case had a worn spot and was shorting. Replaced wire. The condenser would give one spark then nothing until a few minutes then another spark The Flywheel timing mark has been found engine was in time.
Thanks all, ken

 

[Soundguy]

Glad yuo got'er done. Love to hear success stories like that.

soundguy

 

[scott_vt]

O'k Now have the Farmall B running the magneto had a weak condenser but the problem was the wire going to points through the case had a worn spot and was shorting. Replaced wire. The condenser would give one spark then nothing until a few minutes then another spark The Flywheel timing mark has been found engine was in time.
Thanks all, ken

Mornin Ken,
Glad to hear you got the problem solved ! I figured it had to be something with those points, kind of forgot about that wire though ! Glad your up and runnin again ! Those old Farmalls sound great dont they !