Carb fuel bowl level check

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Indianacub74
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Carb fuel bowl level check

Postby Indianacub74 » Sat Jun 08, 2024 6:55 pm

I got a quick question.
What would be a easy way to check if the fuel level in the carburetor fuel bowl and see if it is right level. The service manual says there is a tool for this test. I didnt have much luck on finding the tool or if they are even made anymore. I figured I could drain the bowl into a cup and measure how much fluid comes out. If I did it that away I'd still need to know how much gas should be in the bowl

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Re: Carb fuel bowl level check

Postby Bob McCarty » Sat Jun 08, 2024 7:20 pm

I haven't done this but here is one way: viewtopic.php?f=139&t=100208
"We don't need to think more,
we need to think differently."
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Indianacub74
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Re: Carb fuel bowl level check

Postby Indianacub74 » Sat Jun 08, 2024 8:19 pm

Thanks I did a topic search must have had the wrong word usage. That will work and I got most of what I need to make it.

Indianacub74
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Re: Carb fuel bowl level check

Postby Indianacub74 » Sat Jun 08, 2024 8:31 pm

I wonder how he kept it from leaking at the bowl?? Could you thread the plastic tube

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Re: Carb fuel bowl level check

Postby Eugene » Sat Jun 08, 2024 8:56 pm

viewtopic.php?f=1&t=81463&p=652072&hilit=tool+carb+float#p652072

Re: Carb problems
Postby Eugene » Fri Mar 27, 2009 8:33 pm

Lots of things to look for. A tip. Previously provided.

After giving the carb a through cleaning. I attach a clear plastic tube to the carb inlet. Bowl off the carb, turn the carb upside down. Plastic tube elevated above the upside down carb top, pour some rubbing alchol into the tubing.

Check for leaks, action of the float, and float height.

If the needle valve and seat area is going to leak - this test will disclose it.

Also check the tab on the back side of the float hinge. If not set correctly the needle valve will drop enough to bind in the seat - leaking.
I have an excuse. CRS.
I have an excuse. CRS.

Indianacub74
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Re: Carb fuel bowl level check

Postby Indianacub74 » Sat Jun 08, 2024 9:04 pm

Thank you

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Re: Carb fuel bowl level check

Postby NJ Farmer » Sat Jun 08, 2024 10:27 pm

Very simple tool to make…..get a fitting that will go into the bottom of the carburetor bowl (I think it’s a 1/4 NPT) then a piece of TYGON tube (the yellow fuel line tubing) then bring the tube next to the edge of the carburetor…..turn the fuel on on the gascolator and you have an exact fuel bowl level and it should be anywhere near the top of the carburetor halves.

NJ Farmer

Indianacub74
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Re: Carb fuel bowl level check

Postby Indianacub74 » Sat Jun 08, 2024 10:46 pm

Thanks on the fitting size I was going to take the drain plug to the store tomorrow and size it up

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Re: Carb fuel bowl level check

Postby NJ Farmer » Sun Jun 09, 2024 6:40 am

I checked the parts manual and it strangely doesn’t show the drain plug in the standard 3/4 updraft carb parts breakdown but in the zenith parts manual it lists a 1/8-27 (pitch) NPT plug. I hope this helps but I would bring the old plug with you to size it up.

NJ Farmer

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Re: Carb fuel bowl level check

Postby Gary Dotson » Sun Jun 09, 2024 7:54 am

1/8 npt for the IH, as well.

Indianacub74
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Re: Carb fuel bowl level check

Postby Indianacub74 » Fri Jun 14, 2024 5:43 pm

The first line is the top of the bowl. The second line is the fuel level. The third is where the fuel is when the tractor is running. Shouldnt the fuel level stay the same?? On start up it sucked all the gas out of the hose then slowly came back to the third line. Any advice on what to do or if I'm doing it wrong
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NJ Farmer
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Re: Carb fuel bowl level check

Postby NJ Farmer » Sat Jun 15, 2024 6:46 am

The fuel level drops as it is being sucked up through the venturi of the carburetor. The bowl level WILL be lower when running and should not be the same level when the engine is stopped.

NJ Farmer

If you have problems with it running I would check the main jet for any blockages and CORRECT drill size see maintenance manual for specs. The reason I say that is there are TWO different IH carbs with different part numbers stamped on the top plate and they have TWO different main jet sizes….ask me how I know!

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Re: Carb fuel bowl level check

Postby Don McCombs » Sat Jun 15, 2024 7:32 am

Actually, there are at least seven different carburetor part numbers and at least three different main jet sizes, that we know of. All have differing combinations of main jet size, air bleed size and discharge nozzle style and size.
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Re: Carb fuel bowl level check

Postby Eugene » Sat Jun 15, 2024 9:14 am

Can't really tell from your photos.

Fuel level in bowl, tractor not running, should be at the bottom of the carburetor bolt boss. To the left and up a bit from your second mark.

Tractor running, fuel level in bowl will drop a bit, but not as far as your photo appears to show. Guessing, maybe 1/4" lower fuel level.

Couple of things. Float not set correctly and maybe a fuel flow problem.
I have an excuse. CRS.

Indianacub74
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Re: Carb fuel bowl level check

Postby Indianacub74 » Sat Jun 15, 2024 10:47 am

It's a cheap 30 dollar carb. Was put on before I got it. With rebuild kits not fitting. Hesitant on taking it apart. I'll re do the test when I get back home.


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