Super M starves for fuel

Keno Farm · May 2, 2010

My Super M starts great with choke applied. Then when the choke is released the engine runs fine for 30 seconds or so then begins to act starved. Pulling the choke will revive the engine but it must be quickly released and then the whole process repeats itself. Adjustment of the fuel and air seem to have no effect. Any suggestions would be appreciated.

Rick(MN) · May 2, 2010

Start by taking the fuel line off at the carb. Check to see that you have a good steady stream of fuel there. Reattach and pull the plug from the fuel bowl to check stream there, If both are good, then it is likely that you have an obstruction in either your idle or load circuits in the carb. One other thing, an intake leak will often show the same symptoms.

Tom Fleming · May 2, 2010

Your carb is starving for fuel. could be stuck float valve, clogged input line, clog input screen, clog at the tank end, clog in the sediment bowl screen, plugged jet.

Make sure you are getting good fuel flow all the way to the float valve. If you are, then the jets are proably the culprit.

Eithe way, the carb needs to be taken apart and checked for "clean", and it if isn't, make it that way.

El Toro · May 2, 2010

Open that main jet adjustment screw to see if that fixes the problem. This will enrich your fuel mixture. Even garden tractors have that adjustment. Hal

sd pete · May 2, 2010

Check the inlet screen.

glennster · May 2, 2010

if you have an aftermarket in line fuel filter, be sure it is for a gravity flow system and not a pressurized fuel system. if you need to run an in line, try a napa 3031 or 3032 filter, they are full flow for gravity systems.

armand tatro · May 2, 2010

Do you have that goofy fuel cap with the gauage in it? If so make sure the cork float is not coming apart as those pieces of cork can cause all kinds of problems! Also if you have a piece of hose in the fuel line it could be rotten on the inside and not letting fuel flow to the carb. Armand

armand tatro · May 2, 2010

Do you have that goofy fuel cap with the gauage in it? If so make sure the cork float is not coming apart as those pieces of cork can cause all kinds of problems! Also if you have a piece of hose in the fuel line it could be rotten on the inside and not letting fuel flow to the carb. Armand

Keno Farm · May 3, 2010

Thanks for the suggestions. I have disassembled, cleaned and reassembled the carb, cleaned the filter and at the moment have no element in the filter. The supply line, screen etc are clean and non-restricted. Have decided to rebuild the carb as the best and only remaining option unless someone could offer a better suggestion. As I have told my son for years it only takes three things to make an old engine run - air, fuel and ignition. Seems like that is still a good rule.
Thanks

Dougct · May 3, 2010

I just went through this with my M.I even put in a new needle but because I let it sit and don't use it enough I found that when I pulled my bowl off the new needle was stuck shut,and yes I put treatment in my fuel.My solution was to shut the gas off so the float doesn't sit closed all the time and also i put in Marvel oil to lube it a little seems to work great now.

Super M starves for fuel

Keno Farm

New User

Rick(MN)

Member

Tom Fleming

Well-known Member

El Toro

Well-known Member

sd pete

Well-known Member

glennster

Well-known Member

armand tatro

Well-known Member

armand tatro

Well-known Member

Keno Farm

New User

Dougct

Member

Similar threads