farmall cub question

[steave1288]

Hello all... I have a 1956 Farmall cub all original and still 6 volt... My question is, with the ignition on (ignition switch out) should I have power at the distributor wire... ( wire from coil to distributor) also... Second question: With the ignition on and a test light to ground should the test light light when I touch the distributor housing? and if it does that would mean the distributor wire is grounding against the distributor housing, Correct? and finally... what side of the coil should the distributor wire go to + or - Someone has had their hands in this tractor before me... So I am not sure everything is hooked up correctly... Thank you..

 

[old]

6 volt cub should be a positive ground so the positive side of the coil should go to the distributor. With the points open if you hook a test light to either side of the coil the light should be on. With the points closed the light should be off. As for the distributor housing it should be well grounded so only way the light should come on is if you have the light hooked to the non ground side of the battery

 

[steave1288]

Ok gotcha Thank you.... Is there a way to test if it's positive or negative ground? Thanks so much..

 

[old]

No test you simply look at which battery cable goes to ground. Being 6 volts unless someone messed with it it should be hooked so the negative battery cable goes to ground simple as looking at it

 

[used red MN]

Number 1 It depends if the distributor cam lobe is at a point in rotation where it is holding the points open or if the position is where it is allowing them to close or contact. Usually an engine stopping on its own free will stops at a position where the points are closed but not always. If the points are closed and contacting properly there should be no power showing on that wire from the distributor to ground. However, in your case it will show power due to the answer of the next question. Number 2 The housing of the distributor should at NO TIME show power to ground. Have you had this tractor apart and painted it up all fancy? If so you need to remove the distributor and clean the paint off the surfaces that touch together when the distributor is installed. Or maybe it is an old rusty machine, will need cleaned either way. The ground path for the distributor side of the coil through the contact points is being ..insulated.. from the engine ground. And it does not mean you have something grounding between the moving contact point and ground, it will show power in that way because the electricity is coming through the primary winding of the ignition coil. It is just a long wire wrapped around and around inside the coil. For the last question you describe the tractor as original 6 volt system, in that case original configuration is POSITIVE ground at the battery. In this type of system to align coil polarity correctly you have to connect the ..plus.. + terminal to the distributor. Now I will see if JAN beat me to the punch, hopefully he had some papers to grade.

 

[steave1288]

ok... But if the negative side of battery goes to ground, then wouldn't that be Negative ground?

 

[Jim Becker]

(quoted from post at 23:04:21 03/29/22) ok... But if the negative side of battery goes to ground, then wouldn't that be Negative ground?

I think old misspoke when he said that. (He had everything right in his first reply.) The positive side of the battery goes to ground.

 

[old]

Yes my bad it should say positive battery cable to ground sorry about that

 

[steave1288]

Thank you... Thats what I figured...

 

[steave1288]

Ok....Understood... Thanks so much...

 

[steave1288]

Understood.... Thank you.... And if the battery negative side goes to ground, then the distributor wire should then go to ground side of coil?

 

[old]

What ever your ground is that should also be what the coil is as in the distributor is ground

 

[steave1288]

Thank you so much guys... I have a good handle on it now... Thank you.... be safe and stay well

 

[John T]

Its simple actually. With the Ignition on IF ALL IS RIGHT a test lamp on the coils OUTPUT (To distributor) will be ON when points are open or OFF when closed WELL DUH

A test lamp on the coils OUTPUT to distributor would flash ON (points open) and OFF (points closed) as the engine is slowly rotated..

YOUR QUESTIONS

With the ignition on and a test light to ground should the test light light when I touch the distributor housing?

The distributor housing IS GROUNDED so a test light to ground and dist housing is GROUND TO GROUND NO LIGHT !!!! See above



and if it does that would mean the distributor wire is grounding against the distributor housing, Correct?

Dist housing is grounded and frame is grounded so ground to housing = no light

The side pass through terminal IS INSULATED OFF DIST HOUSING... With points CLOSED it goes to ground, with them OPEN it goes nowhere
other then coils output


and finally... what side of the coil should the distributor wire go to + or - Someone has had their hands in this tractor before me.

If POS ground coils wire to dist is +,,,,,,,,,,,if NEG ground coils wire to dist is -


FINALLY To find the cause of no fire with ONLY your eyes maybe a test lamp work through my Troubleshooting Procedure.

http://www.ytmag.com/cgi-bin/viewit.cgi?bd=farmall&th=5745

John T
John Ts Ignition Troubleshooting

 

[old]

I'm left handed so also dyslexic so sometime get things backward. Thinking right but type wrong. LOL

 

[used red MN]

John T, apparently you did not read my reply. Could have saved yourself a lot of typing. You did add a little more detail about the distributor pass through terminal. I am sure the OP will appreciate your reiteration and probably more so your troubleshooting guide. I did not notice you to be the type that plowed into a a post without considering what was already said. Oh wait a minute ..lawyer.. game off! ; > )

 

[cuby]

To tell the difference on battery posts the larger post is usually positive.

 

[John T]

You did add a little more detail about the distributor pass through terminal. I am sure the OP will appreciate your reiteration and probably more so your troubleshooting guide

I sure hope so, My Troubleshooting Procedure has helped a lot of gents, I'm always glad to help out.

Best wishes and God Bless

John T