Yes more carb issues

So Ive had this marvel shebler carb apart quite a few times now. The first couple times I simply cleaned with a can of brake clean and blew it out, still wouldnt run, it would fire like it was trying but no luck. Then I got serious with it and bought some Chem dip carb cleaner and immersed the carb for 2 full days, then ran a small wire through all the passages and blew it out. Assembled the carb and it fired right up and ran like a champ. That was around a week ago, I went back out to readjust the governor rod.. tried to start the tractor up and it was acting like It did before I cleaned it. It acts like its not getting gas. The needle for the shut off valve wasnt sticky, Indidnt have time to mess to much with it this eve, minday will be the day I can work on it a little more. Im a little frustrated with it. In case I throw in the towel and buy a new carb, Whats the best aftermarket carb for the money? I see they vary in price from 55$-250$
 
Many of these ol TO's sat in the blackberries or years before some resurrected them so there is probably a load of debris
and/or rust in the tank and that's maybe causing your problem. You know there is a screen at the fuel bowl inlet, don't
you? Have you removed the drain bolt on the fuel bowl to see if you have a full flow of fuel to the carb?

The M-S carbs are among the simplest carbs every designed, but it need to be thoroughly cleaned and adjusted properly. (No
less than a full turn out on the power jet screw and about one turn out on the idle air screw for starters.) You got it to
run correctly so find out why it's not running now.

Not all non-starts are due to carb issues. Ignition problems are more probable than carb problems. So check your spark. It
needs to be fat and bluish-white, the color of lightning.

Good Luck.
 
Thanks jerry, the tank is almost as clean as a brand new tank, Im checking the fuel flow tomorrow. I have great spark so yes Im still scratching my head. Ill figure it out though..
 
Go with what Jerry said and check fuel flow. Disconnect at the carb then turn on fuel shutoff. You may have a clogged screen or other
debris in the line. You can find new screens here or at TSC store, maybe even automotive store. Youre going to want to replace the gasket
anyway.
 
You want to pinpoint the problem without making multiple changes and not
knowing what solved it, or creating more problems in the process.

Start with doing nothing first, see if it will start and run. If it does, run
it as is until it fails again. Need to catch it in the act!

First place to check is spark. Check it again just to say you did. Another
reason to check spark first is so you are not dealing with electrical with
gas spilled everywhere!

Then remove the drain plug in the carb bowl. Catch the flow in a big clean
glass or jar. It should free flow a heavy stream, then slow as the bowl
empties, but it should continue to flow, not slow to a drip or stop. Let it
flow for a good while to get a long term test.

If the flow stops, try loosening the gas cap.

Then take the fuel line loose at the carb. If you get good flow at the line,
but not through the bowl, that narrows it down to the inlet elbow screen, or
the needle valve is sticking, float failing to drop (touching the side), or
level set too low. I have seen the needle too big for the seat, it wedges
instead of dropping down when the float drops. The seat bore can also be
burred when tightening with a screwdriver.

I don't remember, but is there an inline filter? Those can cause intermittent flow issues. It was never intended to have an inline filter, just a straight shot from the tank through a 5/16 steel line.

I doubt there is any unsolvable mystery with the carb, they are just too
simple and proven. If you do decide to replace it, I would prefer a rebuilt
factory carb over the new aftermarket. The aftermarkets are aluminum, not
iron. They are also generic fit all's, made to fit a ride range of
applications. It will not be plug and play, you will have to play around with
the linkages.

I think you will eventually find the problem if you just persevere in a step
by step process. Let us know...
 
Hello, Put a new set of plugs in it and i bet it will start right up, You flooded it and the fuel we have today puts a coating on the plugs
that shorts them out. Newer vehicles have high energy ignition and can burn it right off, the older stuff doesn't.....and you have to clean
or replace the plugs after you flooded it..Hope this helps you....ED
 
(quoted from post at 10:30:00 05/08/22) Hello, Put a new set of plugs in it and i bet it will start right up, You flooded it and the fuel we have today puts a coating on the plugs
that shorts them out. Newer vehicles have high energy ignition and can burn it right off, the older stuff doesn't.....and you have to clean
or replace the plugs after you flooded it..Hope this helps you....ED
I just came in from pmessing with it, and heres what I came up with; so I made a new rod for the carb linkage and it might have been a hair short.. it just so happens I opened up the throttle on it wide open and tried to start it this time it fired right up and idled perfectly , even though the throttle was in wide open position it was only idling, I can manually throttle it using the governor rod. I need to lengthen the rod to get more throttle, in short by a half inch. But she runs!
 
Getting the rod adjusted is a critical adjustment.

The way I determine it, set the dash lever in the middle.

Disconnect the clevis from the governor arm. You are now in control of the
engine speed, so proceed with caution.

Have an assistant to be in control of the ignition and starting.

Hold the carb link in the idle position, start the engine.

Slowly bring the engine RPM up while watching the governor arm. As the RPMs
come up, the arm will start to move back. With the engine in the 2000-2500
RPM range, the arm will stop moving back. That is the end of its travel.

Carefully note that position. Shut the engine off.

Now, adjust the rod clevis length so the noted position of the arm will bring
the throttle shaft against the idle stop screw.

The reason you have to go through this is because the governor arm will
travel much further, but the governor can only push it back so far. There is
just enough travel to move the throttle from wide open to idle.
 
Thanks for that, theres so much of this stuff the book doesnt cover. Im sure the rod arm needs to be longer, but Ill be able to determine exactly how much longer by watching the governor rod travel. Ill work on it more tomorrow afternoon. Ill have my wife help me. Again, thanks.
 

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