12 volt issues

I bought a 1947 8N recently and it didnt run at the time that I bought it so I figured that I would do some necessary tuning to it before I tried to start it. Additionally it needed a head gasket replaced. I did the head gasket job and put new plugs, wires, sediment bowl, and points and rotor replacement. Now I cant get it to start and I am not sure where I went wrong. The system has a 12 volt generator on it but I am not sure if the wiring has been updated to 12 volt. The starter solenoid is definitely a 6 volt. I am not sure how to tell if the starter is 12 volt or not. Also I am not quite sure if I put the points back in properly cuz I simply took the old ones out and put new ones in. My big question is this, When I replaced the points should I have turned the crank to ensure TDC and then replaced them? I get the engine to turn over but am not getting spark to the plugs. One other big thing is that the cable going from the positive battery terminal to the starter solenoid started to melt the rubber coating while trying to start and then I couldn"t get the lead off of the solenoid and ended up cracking the solenoid so I definitely have to replace that. I am wondering if I shouldn"t go back to square one and replace the wiring harness and take the points off and start at the beginning. Any help would be greatly appreciated I am kinda new to this and just want to get it done right. I thought this would be the place where people might have been through this problem before.
 
Not sure where to start I would take off dist. since it dosen't sound like you din't give your points any gap. The melting may be your still on positive ground you can leave the 6 volt cables but the one going to solenoid is your + cable now.
 
The wiring does not need to be "upgraded" to 12v. 6v or 12v, it doesn't care, but the age/condition of the wires does matter.

Check out tip # 42; you will be very happy if you replace the wiring. That includes a new terminal block, resistor & ignition switch. And, new battery cables as well.

It does not need a 12v starter or solenoid. Just replace the 6v solenoid w/ the correct OEM part.

Check out tip # 39. That tractor will be nothing but a source of frustration & a money pit if you don't get the manuals & have at least a basic understanding of it's operation.

As to the points.......

The front distributor was designed to come off of the tractor to replace/adjust the points. Remove the wire on the coil, remove the coil bail, remove the distributor cap & take the two bolts off. The base of the distributor has an offset tang & can only go back one way unless you really force it on.

Before you check anything else, make sure you have the correct voltage at the top of the coil. It should be battery voltage w/ the points open & about half that w/ the points closed.

If you do not have the correct voltage at the coil, that’s your problem.

Assuming that the bushings & advance weights are ok, & that you have correct voltage to the coil, the most common electrical failure (no spark, weak spark) points on the frontmount are:

1. The insulator under the brass concave head screw.

2. The insulator at the end of the points where the copper strip attaches.

3. The copper strip is broken or grounded to the plate.

4. The condenser wire grounding.

5. The pigtail/tab not making contact.

6. Incorrect positioning of the spring clip on the plate causing the pigtail to ground.

7. Incorrect seating of the coil on the distributor due to a loose bail or no gasket; the coil must not move at all.

8. Water/moisture inside the cap due to gasket failure or the absence of a gasket.

9. Dirty/corroded/incorrectly gapped points

10. Burned rotor, cracked/carbon tracked cap.

Make sure you are using quality parts; the points should have a phenolic rubbing block & not the cheap white plastic crap. Use only Wells, Blue Streak or Echlin brand points. (* see below) Be careful not to ground the tip of the condenser wire to the body of the distributor when you replace the points. Do not break the little copper strip that goes to the points. (If you do, make another out of the old set of points) Also, make sure the condenser wire does not go through the same opening in the distributor that the coil pig tail does. The condenser wire goes the opening on the top right. Check the point gap, .015 on all four lobes. Make sure the blade is at a perfect right angle to the points & you want to feel just the slightest bit of drag when you pull the blade through the points. Set the points on the highside of the cam. Make sure you have the star washers under the screws on the points. Dress the points by running a piece of card stock or brown paper bag through them. New points sometimes have an anti-corrosive dielectric coating on them & old points can corrode or pick up grease from a dirty feeler gauge or excessive cam lubricant. And, don’t forget to lube the rubbing block w/ cam lube; not Vaseline, not bearing grease, but cam lube. (** see below)

Now, set the timing. Get a meter or test light, a 21/64” drill bit & a metal straight edge. Put the distributor face down w/ the condenser on the left & the timing plate lock screw on the bottom. Look at the end of the shaft: it has a narrow side & a wide side. Make sure you can tell the difference. Now, place the drill bit in the bottom mounting hole. (this will be your reference point for measuring) . Next, place a straight edge on the wide side of the tang on shaft as shown in fig. FO83 in the I&T FO4 manual. Rotate the shaft CCW (as viewed from rotor side OR CW as viewed from back/tang side) until the straight edge is ¼" beyond the outside edge of the drill bit you stuck in the distributor mounting hole. At this distance, the distributor points should start to open. (get your meter/light out now & check) If not, loosen the timing plate lock screw and turn to advance or retard the timing. (move the plate down to advance timing, up to retard) Remember, each one of those little hash marks represents about 4* of timing. Keep adjusting until you get the proper ¼" setting. (if the plate won’t move, you might need to remove the big C clip to loosen it a bit) As you’re adjusting, eliminate backlash by turning the shaft backwards (CW as viewed from the front) and bring the shaft forwards (CCW as viewed from the front) to measure your setting. This ¼" setting will get you static timing at top dead center.




Now, do a continuity check.

1. Coil off, cap off, points open. One probe on the brass screw & the other on both sides of the open points. On the side closest to the cam, you should have continuity. Not on the other side! If you do, you will also have continuity everywhere because the points are grounded.

2. Coil off, cap off, points open. One probe on the brass screw & the other anywhere on the body of the distributor. You should have no continuity! Now, rotate the tang on the distributor....as the points open & close, you have continuity (closed) and lose it when they open.

3. Coil on, cap off, points open. One probe on the lead on the top of the coil, the other on the cam side of the open points. You should have continuity!

4. Coil on, cap off, points open. One probe on the lead on the top of the coil, the other anywhere on the body of the distributor. You should have no continuity!

At this point, I just put the distributor, coil & cap all back on the tractor as a unit. The reason I do this is because it is real easy to get the cap or coil mis-aligned trying to put it back together one piece at a time & the result is something gets broken or you get a ‘no spark’ problem.

It's possible to put it back on wrong & break it. Look at the slot on the end of the cam shaft. What ever angle it happens to be, turn the distributor tang to match it. Make sure you can tell the wide side from the narrow side on both the cam & distributor! (close counts) Then place the distributor on the front of the engine, gently push it in place & slowly turn the distributor body until you feel the tang slip into the slot. Rotate the distributor body until the bolt holes line up. Then, hand tighten the two bolts until the distributor body is flush w/ the timing gear cover.

Finally, double check your firing order & plug wires. It’s 1-2-4-3, counterclockwise. It’s very easy to cross 3 & 4.

Post back w/ results & any other questions.


* NAPA part numbers:

· Points: FD-6769X

· Condenser: FD-71

· Rotor: FD-104

· Cap: FD-126

** Distributor cam lube: http://www.autoanything.com/fluids-manuals-63-771-1978/201A1960.aspx?kc=FFPMM
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50 Tips
 
Sounds like you tried to replace the points with the distributor on the tractor.It's two bolts and a wire to remove and work on the kitchen table.If you're married,use newspaper under the dist.---lha
 
Thank you so much between the FO-4 and your very descriptive steps I got the tractor up and running this weekend and she purrs like a kitten.
This tractor definitely doesnt like 4th gear she bucks like a mule out the gate. But other then that I am well on my way towards getting going on my restoration. Thank you again. My email is [email protected] I will undoubtedly run into more problems the deeper I go into this and it would be nice to know somebody who has already went through the steps.
 

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