Super A Starting Problems

djhammerd

Member
My Super A is still 6V, positive ground. It will not fire. I cannot see a spark when I pull a plug wire, put a rod in it and hold it next to a ground while turning the engine over.

I know this may not be a good question, but is there a way to hot-wire this tractor (around current wiring harness) to see if I can get a spark?

If I get a spark that way, would it generally mean I have a bad wire or short somewhere?
 
hot wire: run a wire from neg battery post to the neg side of the coil and crank the engine. if the engine starts, then the problem is in the switch or wiring.
 
If you are getting power from the switch to the coil, then it may be the points. Have you removed the distributor cap and watched the points as you turn the engine over? You should see an arc if the sun is not too bright. If you don't see an arc, the points may need to be filed a little with emory cloth or a finger nail emory board.
 
If there is still no spark, the points may be coated with non conductive material. (it happens with no input from the owner) To clean, use a match book starter strip, or 340grit paper. Wipe after cleaning with a folded dollar bill. Gap is .020" when the cam is pushing them open as far as possible. Jim
 
(quoted from post at 22:27:55 02/18/14) Does it have a Magneto or a distributor?

Vern

It has a distributor. I'll clean the points with something, check the clearance and try the hot wire this morning.

Thanks for the suggestions.
 
Don"t guess, troubleshoot.

Put a test light on the side of the coil connected to the distributor. Crank engine and light should flash on and off. If it is not lighting at all, check for power at the other side of the coil, or something shorted in the distributor. If it is staying on all the time, points are dirty or something is open in the distributor.
 
I have been troubleshooting a little...

Keep in mind, it has been several years since this tractor has been run. If I had to guess, based upon what the previous owner said, I would say 3-5 years.

Seems like I made some progress, but no firing yet.

Things I've done..

1. Opened the carb, everything was clean. No deposits anywhere. Needle valves are set to 1.5 turns. I didn't clean the carb because it was clean inside (no varnish either). I may end up cleaning it later.

2. I tested the coil as per suggestions online. With no wires attached, it has about 1.2 ohms resistance between terminals. This is what is expected (according to the instructions) if the coil is good.

3. I tested the condenser as per instructions online.

Disconnect condenser , set meter on ohms, put red meter lead on condenser wire, black lead on condenser body, hold for about 30 sec. This is supposed to put a 1.5 volt charge into the condenser. Switch meter leads and watch meter needle. When I touched the leads onto the condenser, the needle jumped a little to the right. This is supposed to be indication that the condenser is OK. Supposedly it took current and discharged.

I realize those two tests don't guarantee that the coil and condenser are top notch, but they are the only tests I found online that I can do.

With the condenser and coil in place, and the (-) side of the coil having a wire going directly to the negative post on the battery (hot wired), with the wiring harness out of the picture (except the (+) side of the coil wire going to the distributor)...... I saw a spark between the points when they opened/closed when I turned the engine over (occasionally, not every time).

Gas is going into the carb. I can drain the bowl with the petcock (bottom of bowl) and the bowl will fill again and gas flow stops (float and needle valve is working). I know this because I connected up a "tiny tank" with a hose to the carb and can see when gas is flowing.

I disconnected the air filter and squirted starter fluid into the carb a couple times when I was trying to start it. No firing.

I did choke a little. I don't THINK I choked excessively, but ???

Compression and suction is there (I could hear it in the exhaust (muffler is off, tin can over it was jumping on exhaust manifold) and I could feel it at the carb intake with my hand over the opening for a couple seconds.

I have not measured compression (but I could, and probably will).

I am getting spark to the plugs, but it looks weak. I took two different plugs out (one at a time), grounded the side of the plug and turned the engine over. I got a consistent weak spark(looks to me anyway).

Plugs look good... By the way, what do YOU recommend I use for plugs?

I bought one of those gismos (Inline spark testers) that you put on a plug, then put the plug wire on the other end. It has a bulb that is supposed to flash when it gets the jolt from the distributor. I did not see any flash when I was turning the engine over (remember, I did see a weak spark when I took the plug out, left the plug wire on it, grounded the plug body and turned the engine over).

When I had one of the plugs out, I sprayed starter fluid in and quickly put the plug back in and turned the engine over (did not fire).

[b:e7ac77e558]This has to be a clue.... The coil was getting warm (not hot, just warm). [/b:e7ac77e558]

I was disconnecting the hot wire when I wasn't trying to start the engine.

I filed the points, set them points to .020, cleaned very little crud off the terminals in the distributor cap, bent the metal tab up a bit on the rotor and cleaned the end of the rotor that sweeps by each terminal in the distributor cap.

Ensured the distributor wire was all the way in (spark confirms that anyway).

The engine turns over SLOW, but it does turn over. Not dead slow, but with no urgency. Something I just thought of... I need to check resistance in the battery cables.

The battery (new) has about 6.3 volts when not under load. I've kept it fully charged.

I'm assuming (hoping) I am not damaging anything by hotwiring the (-) side of the coil to the negative post.

This isn't pertinent yet because it's not in the picture yet (wire to the coil disconnected).... I've cleaned the internal and external contacts on the regulator. I don't know the actual condition of the regulator or generator, but the assumption is they should be OK. I will know more about them when I put the wiring harness back into the picture. Assuming I will be able to get the engine running with it being hot wired, I'll check those out with the engine running.

The previous owner WAS hot wiring the coil to get the tractor to run.

I'm out of ideas... Anyone have suggestions??? I know this is an extremely simple electrical system, so I have to be close.

I need direction from someone with more experience than I have...

It seems like the next step would be to replace the coil and distributor, but I'm not sure.

Is it possible the condenser is just not taking a serious charge?

The previous owner said the tractor was running fine when he stopped using it. He was using it to mow about 4 acres (belly mower) and bought a new yard tractor to replace it.

Thanks in advance for the direction I know is coming...


Update. I did go and check the resistance in the battery cables. There is none...
 
Another update...

I took off the throttle line (to the governer) so I could remove the battery. I have not put it back on, so the position it settles to is where the carb throttle has been. I held the governor lever back once during the tests I did, but I cannot be sure I had spark when I did that.

It's possible that the carb throttle has been closed for almost all my testing (I'm so embarrassed if that's the case).

I'll put the throttle rod back on temporarily so I can set the tractor throttle about mid range to try to start it.

What I don't know (yet) is where the carb throttle butterfly is when the governor is in it's un-controlled resting position..

Another thing about the governor.... When I look into the opening the cap is on, it doesn't appear to have oil in it. It's not clear if that case is a reservoir just for the governor or not. I read online somewhere (it may have not been here), that that cap is to be used to put oil in the crankcase. Someone disputed that and said the governor doesn't drain it's case to the crankshaft.

Question: This engine is a C-123... do I need to put oil in the governor.... just for the governor? If so, what oil do I use?

Again... I've got shop manuals coming that should cover this engine, but they aren't here yet...

Thanks for your patience with me..
 
Just came back in from hooking up the throttle line to the governor and setting the throttle (at the driver lever) to about half speed.

The tractor still didn't start. I used a little starter fluid directly into the opening of the carb again.... and choked a bit also.

It did fire once... Only once.

I also put the inline spark detector on a couple plugs again. There definitely is spark, but again it looks weak. When I tried that earlier and didn't see the bulb light, there must have been too much daylite.
 
Did you clean and gap the points? Did you pull the plugs and heat them with a propane torch then reinstall? Did you try putting WD40 (a 1/2 second spritz) in each hole before putting the warm plugs back in? Did you try pull starting it? Jim
 
(quoted from post at 17:48:11 02/19/14) Did you clean and gap the points? Did you pull the plugs and heat them with a propane torch then reinstall? Did you try putting WD40 (a 1/2 second spritz) in each hole before putting the warm plugs back in? Did you try pull starting it? Jim

I did clean and gap the points. I can try warming the plugs and using WD40 tomorrow.

I can't really pull the tractor until the snow is gone and it dries up a bit (maybe next week). That will tell me if faster turning-over will help.

All good ideas. Thanks!

I think I may move the ground cable over to a bolt on the starter also, just to be more direct for the troubleshooting.
 
Have you noticed any gas dripping out the bottom of the carburetor when you choked it? Just wanted to make sure there was gas in the carburetor. If you think the engine is not turning over fast enough, you might try pulling the tractor (use 4th gear) or jump it directly at the starter with a 12 volt source. I would stay away from starting fluid.
 
(quoted from post at 19:14:27 02/19/14) Have you noticed any gas dripping out the bottom of the carburetor when you choked it? Just wanted to make sure there was gas in the carburetor. If you think the engine is not turning over fast enough, you might try pulling the tractor (use 4th gear) or jump it directly at the starter with a 12 volt source. I would stay away from starting fluid.

I have drained the bowl of the carb from the petcock on the underside of the carb, so I know gas is in there. And yes, I did have gas dripping one time.

If I don't get it started before Sunday, I may be able to pull it. The snow has to melt here first... before I can move the tractor to where I can pull it, I don't want to mess up my yard.

Using a 12 volt source for a starting test (without the generator/regulator involved again) has crossed my mind. I was just hoping to get it running using the six volt system.

I am considering changing over to a 12 volt system, but if the 6 volt system works well, I may not convert.


It's my understanding that I'd need to install a ballast resister between the battery and the coil (to protect the coil) if I test with a 12 volt battery.

Is there any reason I'd need to change to a negative ground for the test?
 
If the engine is turning over slow, that may be the real clue to the failure to start, and the modest spark. The battery cables are likely to be made for a 12v car. They must be at least 2 gauge, or better 0gauge cables. Slow cranking indicates low voltage to the coil. Pretty easy to check the cables for size. At least pencil sized copper or first grade size if you want the best.
A way to test the voltage thing is to use a different battery to make it start, while using the normal battery to power the ignition. TO do this disconnect the big and small wire from the starter switch and bolt them together separately wit tape over them to prevent grounding. Then use a 12v battery to jump directly to the starter stud (with the nut put back on it) and to ground.
Polarity does not matter, the starter will turn well, and in the correct direction. With the jumper battery hooked up just turn on the ignition and activate the starter switch. This setup does not compromise the regulator, or lights, or generator because the 12volts is only spinning the starter, and is not affecting the 6volt normal setup. Jim
 
(reply to post at 20:42:11 02/19/14)

I understand..... I will isolate the starter and use a 12 volt battery to spin it. I won't need the ballast resister.... and, if it works, it will confirm that the ignition will work with 6 volts.

THANKS for the great suggestion. I'll post the results tomorrow.

Incidentally.... I think the cables are 0. They are about a half inch thick. I also tested for resistance and there is none, at least my meter is showing 0 ohms end to end.
 
I decided to try one more thing before I put 12 volts to the starter. Actually, this was probably suggested before, but because I measured zero ohms resistance on the battery cables, I hadn't done it yet.

I took the battery and harness cable off the starter switch, cleaned the terminal and cable end, then put just the cable back on. I also put the other cable on one of the starter bolts.

Persistence pays.... The engine turned over a little faster and it STARTED! Of course, its about 50 degrees out there also.

Now to decide if I want to upgrade to 12 volts at all.

I put up a short YouTube video at

http://youtu.be/N7ynxVQrk6w


Thanks, everyone, for your patience and advice.

Moving forward.............
 
I"m not advocating that you should convert it to a 12 volt system. Most of my tractors are still 6 volt and work fine. Just make sure you have the larger battery cables for the 6 volt system. I think the minimum cable size is #1. You can still jump start it from a 12 volt system without damage to the 6 volt system, if you hook the jumper cables at the starter. Hook one to the starter post and the other to the tractor body. No, you don"t have to change to a negative ground. Just make sure the switch is on. :)
 
One of the common problems that I have is a bad ground onnection where the battery cable grounds to the tractor. On the Farmall C, I bought a longer battery ground cable and used one of the starter mounting bolts for grounding the cable. It cranks over really well now.
 
:D I'll be getting a ground cable long enough to go to the lower starter bolt also.

THANKS again everyone, for all the advice to help me get my tractor started. This forum is AWESOME!
 

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