Just completed overhaul & 12v conv. Now won't start

[rexxon]

Did you check to make sure your distributor was timed correctly? They have to be timed from the back side and it is really hard to do with the Distributor seal in place( not impossible just difficult) The seal installation tool I bought from a member here helped alot.

[tractordad]

I rrewired one of my cubs (distributor) using this diagram and it worked fine. I do have a coil with an internal resistor so I did not install a ballast resistor.

[Gary Dotson]

Hi Jim, welcome to the forum! It sounds like you have thought this out pretty well before posting here. I do have one issue with your wiring. The wire from the alternator should NOT be connected to the switch, it should go directly to the terminal on the starter switch, since you are running a volt meter. It does not need to be switched and should be hot at all times. However, that is not keeping the engine from starting. As mentioned before, are you sure you have the distributor in time? Did you remove it? If not, it should still be in time but double check anyway, just to be sure. It seems strange, but sometimes after a teardown these things can be a real bugger to get started that first time. I've gone through that myself, checked & double checked everything and finally gave in and pull started. After that first pull start, it started flawlessly every time. Good luck! Oh' and good luck with the whistle pigs too!

[Jim the PA Hunter]

Hi all,

I bought a 1948 Farmall Cub w/ 7' blade last year and used it to move snow all winter. It worked great but developed a oil leak out the rear main seal.
I used it around the house this summer to pull some dead trees out of the woods for fire wood. Then decided to tear it down. I bought a engine gasket kit, piston rings, rod bearings, clutch plate, throwout bearing, and spark plugs. Split the tractor, replaced the bearing, clutch, rear main seal (rubber coated type). Removed the pistons, had new wrist pins/retainers and rod bushings put in them. Cleaned the grooves. Cylinders were good, only had to remove the glaze. Used standard rings, no overbore. Mains looked good so I did not replace them. Replaced the rod bearings &Torqued the rod bearing caps at 16 ft lbs. Put it back together. Torqued the head bolts @ 45 ft lbs. Gaped the plugs @ .025. Checked the point gap, it's 020. New oil filter. New radiator hose. Changed oil in air filter. New headlights. New bushings and brushes in the starter.
3 qt. of Castrol 5w-30. 50/50 Antifreeze.

I converted the tractor from 6volts to 12volts by doing the following:

Removed generator and regulator and replaced with a ONE WIRE alternator with buit-in regulator. Replaced coil with 12 volt coil that has a built in resistor. Replaced the Amp meter with a volt meter. Replaced the headlight switch with a SPST 20 amp switch. Replaced the ignition switch with a DPST 30 amp switch. I think I have my wiring diagram attached to this post ok.

sw2 is a Single pole single throw 20 amp switch that simply turns the headlights on and supplies power to the rear light switch.
sw1 is a Double pole single throw 30 amp switch that supplies 12 vdc positive to the coil and volt meter when turned on. It also allows the Alternator to charge the battery when turned on.

After putting everything together, I found it won't start. It turns over fine and seemed to actually try once to fire up but didn't. The carb is getting fuel, so is the plugs. The plugs have spark, the coil is firing. I pulled a plug (#4 cyl) and found it was wet. Cleaned it up and tested it for spark, it tested fine. Still won't start. Should I try replacing the condenser? It is the old 6volt one and the original points are in the dist. as well. Even though the points look good, I cleaned them anyway.

Anyone have any ideas?

Thanks in advance! Jim the PA Hunter - love to shoot groundhogs !

[Eugene]

Agree with Gary on the alternator wire to battery terminal on starter.

Also suspect ignition timing problem.

Switch #1. What is the wiring diagram for SW #1? I think SW #1 is also wired incorrectly. It appears to me that the alternator is feeding the ignition system.

[Jim the PA Hunter]

Thanks to all who responded!

Eugene, I also suffer from CRS !

I forgot to mention I replaced the pilot bearing also.

No, I did not remove the distrubutor, nor did I pull the plug wires from the cap.
I did change my electrical wiring to the following diagram:

After changing the wiring I tried to start it again. NOPE...no go.

I pulled each plug and checked them. Each was wet with gas. I cleaned them and then checked each one for spark again. They all fired. I checked the point gap, it was 020. Plugs were .025.
Getting gas, got good spark, won't start. Timing??? How could it be? I did not touch the distributor! I looked up the firing order. Found it was 1342. Pulled the dist. cap and watched the rotation of the rotor. Counting from no. 1 plug I had the firing order at 1432. No how did that happen?????? Switched 3 and 4 around and it fired up right away. Runs and sounds great !! All I have to do is "bump" the starter and it fires up right away. Volt meter is showing 12 vdc when engine is off and goes up to 13.5 while running with a little throttle. Shut er' down and checked oil level...good, Antifreeze...good, and topped off the hydraulic resovour. Topped off the tranny and front steering resovours too. So far so good.

A friend stated that I should not have had the new wrist pins put in because it will not allow any play and possibly lock the engine up. WHAT???
The old wrist pins allowed the pistons to flop side to side. I had a engine machine shop put new pins/retainers and rod bushings in all 4 pistons.
They did not need to bore the pistons. The wrist pins were what was worn and not the pistons which I thought was strange. The old pins looked like their ends were turned in a lathe (stepped down from the center where they were through the rod bushings). They are perfect now and seem to be working fine. Am I missing something? It really runs smoothe now!

Thanks again to all......
Jim
PS: The whistle pigs are in for the winter. I must wait till spring!

[Jim the PA Hunter]

Eugene,

Switch no. 1 is a Double pole single throw switch. I tied pins 1 and 2 together so the added amp rating of the single contact vs dual contacts could be utilized.
12 vdc from the battery was tied to 1 & 2. Pin 3 had the Bat wire from the alternator attached to it along with the pos. 12 vdc to the voltmeter. Pin 4 had the positive wire for the coil on it.
When turning the switch on, basically all four pins were making contact providing + 12vdc to the coil and voltmeter. Also it made a path for the alternator to charge the battery. At least that is what I had going through my mind. I have since taken the Bat wire from the alternator out of the switch equation and moved it to the starter where the battery cable is attached. Now when I turn on the switch it provides pos. 12 vdc to the coil and voltmeter only.

Hope that answers you question. Thanks again to all who responded.
Jim
Got any groundhogs ? Have you ever tried groundhog potpie ??

[Gary Dotson]

Glad to hear you got er goin, Jim! Those plug wire get us all at one time or another. I had assumed your switch connection was as you described and while the double pole switch is not really needed, it will work fine as you have it connected.
NO!! I've never tried Groundhog Potpie! Probably won't be either!