super c won't start! i think it's fuel...

a while back i had the old timer (super c) going - now he's stopped again. to tell the truth, he hasn't really run properly since i've had him...

tried towing him to start him today, but no joy. he coughed and spluttered (backfired a few times too), then ran smoothly, just on tick over for about 10 seconds. this, over and over - each time i towed him.

there was no sign of life, while bump starting, on half to full throttle, and yet when i used the choke, petrol ended up coming out of the exhaust manifold - presumably far too much petrol getting through.

when i've tried cranking the engine with full choke, petrol squirts out of the drain plug of the carburetor (zenith carb). that sounds like too much fuel, but the failure to start except with the throttle closed (and then, only for a few seconds) sounds like fuel starvation!

has anynone any idea what's going on??

by the way, i've just tried adjusting the timing and checked the spark from the plugs - all seems okay. i'm sure it's something to do with fuel!

thanks for any help
lachleaves

How old is the fuel? Try fresh gasoline and new spark plugs.

When you have the plugs out, squirt some oil in there to get the compression back. You have flooded it so bad there is no lube left on the pistons and rings. These engines start best with only choking for 1 or 2 compressions.

where do you live, as in is it cold enough to freeze water? Your air cleaner oil cup could be full of ice and keeping all air out of the carburetor. to test, remove cup, try starting tractor. if it starts and runs, dump cup out in your waste oil bin and thaw it out to remove the chunk of ice.


karl f

Put a new set of points and condenser in it. Hal
PS; If this tractor has battery ignition you need
a fully charged battery.

all great advice fellas, but...

1) the petrol is clean and new

2) i've fitted new plugs and points and checked the gaps and static timing

3) not sure about the frozen air intake - it's been -1 here at its coldest.

anyway, what about it trying to start when the throttle is closed, but no sign of life when its open??

thanks
lachleaves

Might try tearing the carb apart soaking it in carb cleaner for a few days and then take a fine wire and a air compressor and clean out any and all passages in it.

Put new carb kit in it and try it again.

Just because the carb is full and over flowing don't mean it's being injected in to the engine properly. Might be plugged.

Just a thought.

Starting these tractors you can easily dig yourself into a hole that will make you think all kinds of things are wrong, when in reality, nothing is wrong at all. You end up tearing things down, changing timing, getting everything all discombobulated to the point where the tractor will not run at all...

You can quickly go from dry to flooded if you use too much choke. Quick blips is the safest method to use if you are not familiar with the tractor.

Tractors start best at idle, or just above. Vacuum is the highest when the throttle is set to idle or slightly above. Normally they should start at any throttle level, but yours is so far off, the only way it'll even fire at all is under those "ideal" conditions.

First thing at this point, get the carb all cleaned out and set up correctly. Put a "rebuild" kit in. The float level is probably a little off from rough handling. Get the float level right, clean everything out.

Make sure you've got that timing right. Backfires indicate to me you're still a little off.

Two things:
1. You do not need to spend way too much money on a rebuilt carburetor unless yours is physically broken or missing. If you can get the carburetor off the tractor without resorting to a reciporicating saw or acetylene torch, you can rebuild it yourself. It may take 2-3 attempts to get things just right, but afterwards, you will be able to fix any carb.
2. Tow starting will not cure a carburetor or ignition problem. Tow starting is not a cure for any problem, really. It's just a way to get a tractor with a bad starter or weak battery running because you need to use it or move it. With good electricals, a letter series Farmall should fire and run within 2 revolutions of the starter.

What are the plugs gapped at? They should be .025. If they are too wide it takes more to jump the gap when the throttle is open because it has more compression than at idle. (closed throttle)

I have a fully rebuild and restored Super C with all the feature options and attachments, it can be seen on my web site: www.chaselinks.com.

That said, last winter it would not start and we tried several tests and new points, plugs and still would not start even with towing, just would back fire at times.

After all my mechanic help left the scene, I replaced the distributor cap and all was well from there on. There seemed to be a level of corrosion, likely due to moisture, on the inside electrodes.

You may want to change out the distributor cap. By the way, cleaning the cap did not help, as it may have had a samll crack or similar problem.

Good luck.