marvel schebler prob!

stevet86

New User
hello guys am new to the forum! I need some help with the tax 33 carb. I bought a rebuild kit too rebuild the carb. got it all done reinstalled it and every time I turn the fuel back on gas pours out of the intake side of the carb. I've taken this thing apart like 5 times already. Am just blown away how I cant figure out something so simple. so any guidance would be so helpful. and I need to ask if the tsx 33 has a venturi because when I tore mine down it did not have one! thanks again.
 
http://www.carburetion.com/industrial/marvel-schebler.asp

might try this site, lots of information on this brand of carb.
might find what you are looking for,

am sure there is someone on the site that can help you,
I have taken a few apart over the years but am no expert.
however the old tractor does run and start good as of now.
 

It sounds like the float valve is not shutting off the fuel when the bowl is full. The fuel then over flows and runs out the intake.

- Did it flood before you took the carb apart. If not then I would look for assembly problems. Did you leave out the gasket under the needle seat? Does the float hang up on something.

- To test, remove the carb from the tractor and drain the fuel from the bowl. Install a clean rubber hose on the carb fuel inlet, you can blow air into. With the carb upright (as it is mounted on the tractor) with your mouth, blow into the rubber hose. Air should enter the carb. Continue blowing and turn the carb upside down. As the carb is turned, the weight of the float should close the float valve and you should no longer be able to blow air into the carb.

- If the float valve is not closing remove the bowl from the carb and repeat the above test. Observe the float and valve to identify what the problem may be.

- Check the float to verify it does not have a hole and is filled with gasoline. You can sometimes shake them and feel liquid inside. Also place in a jar of gasoline and allow it to set overnight It should be floating at the same level in the morning.

That should get you started.
 
Yes, it should have a venturi. You can google marvel shebler venturi and see for yourself. Looks like a Three Mile Island smoke stack. As Ken said, it does sound like the float is leaking, but you may not have a whole carb, so there could be other issues.
 
does the venturi have anything to do with my problem! and thanks when I get up tomorrow ill tear it apart again.
 
does the venturi have anything to do with my problem! and thanks when I get up in the morning ill tear it down again.
 
Question is can the carb work without the venturi! And it didn't leak before. I swear this didn't have a venturi in it first time I tore it down.
 
I did the air test and when I flipped it upside down for a second it didn't leak air then it did! The needle that came in the rebuild kit looks completely different than the one that's was one it. The one that was on it had a clip that attached to the float. This one doesnt!
 
(quoted from post at 13:18:54 04/02/17) I did the air test and when I flipped it upside down for a second it didn't leak air then it did! The needle that came in the rebuild kit looks completely different than the one that's was one it. The one that was on it had a clip that attached to the float. This one doesnt!

- Yes, you will need a venturi to get the proper signal across the various jets to meter fuel for the engine to run correctly.

- No, I don't believe the missing venturi has any thing to do with the flooding.

- The clip attached to the float is to pull the needle off the seat in the event it wants to stick closed. It should not cause a flooding problem but it should have the clip to prevent problems in the future.

- Since it leaks you will want to look at the needle and seat. Did both come in the kit and did you replace both? Compare the new parts to the ones you took out - is the seat deeper or the needle shorter. Does the needle fit well in the seat or is sloppy? It should be guided such that is point can seal against the small hole in the seat bottom. Make sure there is a gasket under the seat to seal against the carb body.

- If no problems are found, install the old needle and seat. If they seal then the new parts would appear to be faulty.

- BTW, you can do the blow test with the carb bowl removed. Simply operate the float by hand or tip the carb upside down as before.
 
You have two issues; no venture and the float is not shutting off the fuel needle valve.

You need the proper venture so that the carb metering system will supply the correct fuel/air ratio for the cylinder charge.

Your float is not shutting the needle valve so either it is not adjusted properly or the float is full of fuel from a leaky float. Another possibility is that the float is hanging up on the side of the fuel bowl due to a worn pivot pin or bearing. Fuel leakage from a poor seating needle valve is a common situation so most folks just turn off the fuel supply at the sediment bowl.
 
You have two issues; no venturi and the float is not shutting off the fuel needle valve.

You need the proper venture so that the carb metering system will supply the correct fuel/air ratio for the cylinder charge.

Your float is not shutting the needle valve so either it is not adjusted properly or the float is full of fuel from a leaky float. Another possibility is that the float is hanging up on the side of the fuel bowl due to a worn pivot pin or bearing. Fuel leakage from a poor seating needle valve is a common situation so most folks just turn off the fuel supply at the sediment bowl.
 


I made a test fuel tank for trying to figure out a similar problem
many years ago. Get a gallon paint can from the parts place that
mixes paint, braze a fitting to it, piece of rubber gas line, a couple more assorted fittings to hook it to the carb, hang the paint can
higher than carb. get carb on bench LEVEL, [ A C clamp to carb
makes a good holding fixture] put about 1/2 gal. gas in can and
see what happens! Try this after you do the air tests the other guys suggested, I DO NOT LIKE RUBBER TIP NEEDLES.
Also you can install the OLD SOLID NEEDLE in its seat and tap on it a few licks with a small hammer, this will also help to reform small nicks in the soft brass seat. GOOD LUCK, you can do it!!
 

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