farmall super c hesitates, can't open throttle

spade316

Member
Looking for help on my super C. I have a mechanic that has been working on it and is still having problems getting it to run. It will start but runs rough and cannot open throttle without it killing it. I was hoping I could get some suggestions here. He cleaned out the carb, new gasket between intake and carb, spark, timing, compression, all are okay. Cant find any leaks in manifold. It ran good then when I was done raking hay it started hesitating a little like it was running out of gas but there was gas in it. I put new gas in it in case the gas was bad and no difference. It will just run at idle but it is rough. He doesn't think enough gas is getting to the engine but not sure why. Any help is appreciated.
 
I had the same trouble on a Sc. I suspect timing. That was my trouble. I would set time and it would run a little and quit. I finally found the pin in the dist. drive was sheared. You could possibly have stuck advance weights or broken springs also.
 
There are 4 locations where fuel can get restricted. The tank exit to the sediment bowl, the sediment bowl and valve, the small screen in the fitting at the carb inlet, and at the needle san seat in the carb. Remove the drain plug and let run into a can. A pint a minute is plenty, but do it for a couple of minutes at least. Jim
 
(quoted from post at 19:14:25 11/18/16) There are 4 locations where fuel can get restricted. The tank exit to the sediment bowl, the sediment bowl and valve, the small screen in the fitting at the carb inlet, and at the needle san seat in the carb. Remove the drain plug and let run into a can. A pint a minute is plenty, but do it for a couple of minutes at least. Jim

The screen in the carburetor fuel inlet is often overlooked. Many people do not even know it is there.
 
i'm still having no luck. I talk to the guy working on it.(He's retired mechanic from the local Case IH dealership). He said timing is right on, spark is fine, valves are fine, he cleaned the carb again. He said it seems it's not sucking the gas all the way up the intake and then the carb starts to flood, but it feels like it has plenty of suction when you put your hand over the intake. He asked around and some older guys told him to try putting a little transmission fluid in each cylinder to see if it would help and no difference. Compression was 100-110 in each cylinder. I think it almost has to be a carb problem but don't know what else to try. He mentioned changing the intake gasket but he doesn't think that there is a leak though. I might try to find another carb to swap on but hate to buy one not knowing if it is the problem.
 
The spark plugs will give you a lot of information if you know what
to look for...
If the spark plugs look very clean like you just installed them.
Your running very lean...
If the spark plugs look like the color of a brown paper bag.
Your mixture is good...
If the spark plugs look black or black and wet.
Your mixture is to rich or your ignition is not working properly...
Plugs that look black or wet will not fire properly they will misfire
on a load... You need to clean them with a spark plug sand blaster or replace them... But replacing plugs when diagnosing a problem could get very expansive...
Is your super c running a magneto or distributor...
 
One more thing if you see puff of blue smoke when you start your tractor for a second or two... Your valve stem seals are bad...
But is not a big deal...
However if your tractor is always blowing blue smoke from the muffler then your pushing oil... That is a big deal...
Had to repost because this forum will not let me edit my posts...
 
Following up with my C. Spark plugs are black. They show a good spark. The distributor shaft has rotational play. Is there an allowance for the amount of play? I would estimate it will rotate about 20 degrees. It seems run well at idle, but sputters more as the throttle is opened. I have a friend that works at the case dealership to look at it for me. He put a new cap rotor and points on and it helped a little.
 
Black how? Black sooty plugs means it's getting too much fuel. Black sticky plugs means it's getting oil in the cylinders.

Have you replaced the spark plugs?

Also, fire this so-called mechanic and never take anything to the dealership where he works. These tractors are not that complicated and any rookie mechanic that knows the basics of internal combustion should be able to easily diagnose the problem and make the tractor run like a swiss watch. Apparently this one can't figure it out unless the computer tells him what's broke and how to fix it.
 
Plugs are black and sooty. I changed plugs and helped a little. Runs good up to a little over half throttle then starts to rev up and down, getting worse the more the throttle is opened. The carb has been cleaned twice. Once by me then the guy I had working on it cleaned it at his shop.
 
Hope this helps someone else.
Summary of problem. Tractor was running normal then started to run rough like it was running out of gas. Became difficult to start, flood itself, would run okay up to about a little over half throttle then engine would hesitate and surge, or quit running. Had good compression.
Seemed to have a good spark(checked by grounding plugs while turning engine over)
Carb cleaned thoroughly, no change.
Replaced cap, rotor, points, spark plug, helped a little.
Replaced condenser---Corrected the problem.
 
(quoted from post at 19:14:59 12/11/16) i'm still having no luck. I talk to the guy working on it.(He's retired mechanic from the local Case IH dealership). He said timing is right on, spark is fine, valves are fine, he cleaned the carb again. He said it seems it's not sucking the gas all the way up the intake and then the carb starts to flood, but it feels like it has plenty of suction when you put your hand over the intake. He asked around and some older guys told him to try putting a little transmission fluid in each cylinder to see if it would help and no difference. Compression was 100-110 in each cylinder. I think it almost has to be a carb problem but don't know what else to try. He mentioned changing the intake gasket but he doesn't think that there is a leak though. I might try to find another carb to swap on but hate to buy one not knowing if it is the problem.

How is he checking the timing? When I set the timing by the book on a Farmall H, the engine is very sluggish. I always set it by ear and seat of the pants.
 

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