Farmall super A starting problem

[Charlie M]

Guys - I'm out of ideas as to why I get my my Suer A to start. This a tractor listed as a parts tractor I bought last spring for the cultivators and decided to fix it up. It was missing the hood and starter for parts and turns out one cylinder was full of water. I've purchased other tactors with similar motor issues and got them all running quite well so no big deal on this one, right? I had a new set of pistons and sleeves so I put them in along with having the head redone at a local shop. Had to free up the valve train as it was rusted. Converted to 12 volt electrical system (battery ignition) with a resistor and 6 volt coil, cleaned the fuel system and put on new MS carb. Have them on other tractors and work well almost out of the box. I got everything together. I have 125 psi on each cylinder and great suction when I put my hand over the air breather. Finally got it to start up. Had several issues including fuel and radiator leaks and a clutch that wouldn't work so didn't run only a minute or so but ran decent for not adjusting anything. A few more very short starts trying to work out the leaks and one occasion ran it long enough I retorqued the head afterwards and reset the valves. Couldn't see the timing marks so decided to try static timing the engine and then couldn't get it to restart. Decided to to buy a clutch kit and a new sediment bowl and fuel line. I put in the clutch and marked the timing mark on the flywheel while I had it off and installed the new fuel parts. While I had the fuel apart I took off the carb to make sure junk hadn't gotten into and everything was clean and solvent flowed out everywhere it should so put it back on. Still couldn't get it to start. After moving the distributor for timing I finally got it to start and this time I ran it for about 10 minutes. Drove it around and looked for what ever else needed to be done. Ran for about 10 minutes and used a timing light to set timing. Was running good, shut it off and haven't been able to get it to start again since. I have good flow of gas to carb and pulled a plug a couple of times and checked for spark. I even rechecked my valves this morning and almost no change. I know this is kind of long for asking for help but wanted to include everything I have done and rechecked. Cap is wired correct for firing order - 1-3-4-2. Its probably something stupid and I am willing to be embarrassed over it if I get it to reliably start. I'm stumped. Anyone think of something I'm missing or could still be wrong.

 

[used red MN]

I have good flow of gas to carb and pulled a plug a couple of times and checked for spark.

Was good flow of gas to the carb checked at the carb drain plug? If not you don’t know if the gas is getting in the carb. The float needle might have an odd problem of sticking closed. I like to check the points with a test light. Open the distributor and turn the engine until they close. Then with the switch on, the post on the side of the distributor should have no power. Then open and close them to make sure it grounds out the power every time they close. Then crank it and make sure there is a fast on/off blinking. Then double check for spark at a plug.

 

[Duner Wi]

Run jumper from Batt + directly to coil + . This assumes you have 12 volt negative and coil wired correctly. If this doesn’t work carry on with the rest of tests.

 

[Charlie M]

My flow of gas was at the carb drain. That is how I drained the tank to install the new sediment bowl assemble. I checked again after getting the new fuel parts installed. I just tried the battery to coil suggestion, no luck and I checked at the points with a test light as used red MN suggested and that worked fine. Nothing I have tried to this point suggests an electrical problem to the plugs.

 

[wh]

Very rare to occur but I had a FARMALL h quit one day. Did everything including getting the local better mechanic to check it. Had gas, had fire, in time, plugs showed gas to cylinders. He says “when have you changed plugs”? What, not all 4 quit at one time. No way. He says to get plugs. I did and away it went. Ran perfect. Just saying it could be your problem.

 

[used red MN]

Spark plugs can get “rich fouled” fairly easily. This leaves a black sooty residue on them that usually has some amount of carbon in it. The spark will jump to the soot on the electrode porcelain cone instead of firing the gap. I don’t know if this is what you or wh experienced I’m just throwing it out there, something to look at if you pull one out. I would pull the plugs and dump a bit of gas in a couple cylinders and screw them back in to see if it pops off on that. This tells you if it is a gas problem or not.
Edit: I don’t trust those China carbs even though from what I think I read that this carb has run this tractor a bit already.

 

[Charlie M]

I don't know if the MS carb I have is a china carb - never checked. I have several and they are about $200 each so thinking maybe not china carb. All have worked well. I put in 4 new plugs and wires when I changed out stuff in the beginning. I have checked for spark by having grounding the plugs when removed from tractor. Points were new but condenser is the same. Haven't run enough to leave carbon on plugs. Tractor has run a few times after getting everything back together - probably have a total of 20 minutes of run time over 4-5 starts.

 

[grandpa Love]

Sounds strange but a condenser that's going bad can produce enough juice to make the plugs spark but not enough to run the tractor. Try a different condenser. Worst case it doesn't help

 

[Charlie M]

As I sat down here condenser crossed my mine. Never had a problem with a condenser before so wouldn't know the symptoms. I just tried squirting some gas in the cylinders as mentioned and nothing happened. I swapped plugs from my regular A and nothing happened. I just ran that an hour ago so I know its not plugs causing the issue. I'll try a different condenser after supper.

 

[used red MN]

I don't know if the MS carb I have is a china carb - never checked. I have several and they are about $200 each so thinking maybe not china carb.

Sorry if I “dissed” your carb the majority of carbs folks come on here to report they installed on their machines tend to be the $30 “land of almost right” jobs. Full choke it for a “3 count” crank then pull a plug and see if it is wet. If it is you should be good on the fuel side.
When I first came on here I thought the guys preaching a blue spark jumping a 1/4” gap on a spark tester were a bit over the top. Although I already knew that a plug needs more voltage to jump a gap under compression. But I have come around to their way of thinking because a points ignition in good condition can easily produce that output, if it doesn’t you need to find out where the problem is and fix it. Not to shoot down GL but I am thinking if you legitimately test your spark at a 1/4” gap and it’s good the condenser is likely not your problem. Do you have this thing all painted up? There is a possibility that the distributor base is not grounding properly due to paint, especially if you don’t have the holders cranked down tight. Again if it test good with a 1/4” spark this is likely not your problem.
Example adjustable gap spark tester