leaking sediment bowl

[Caroline Chamblin]

I have been mowing after the previous problems that were electrical in nature got solved, distributor was maladjusted. Tractor was running well. After a month of dry weather and no mowing, I went out to mow. Sediment bowl leaks like a sieve at the top where it seals with the cork gasket to the metal housing. I have replaced that cork gasket before successfully. I thought well I will replace it again. Didn't solve the problem this time. I have a few photos here. The screen and cork gasket I got at my parts place (not tractor supply, but not YT either) has a screen with offset hole. Mine has center piece so the old screen was cut with scissors. What do y'all think I should do next?
I see the open/shut fuel valve looks wet with gas. That has not looked wet before. However what I see leaking is around the bowl rim and down the sides of the bowl.




 

[Den N Ms]

Caroline ,The screen has to trimmed so it is just a bit smaller than the inside diameter of the gasket.If it is the same size as the outer diameter of the gasket it will leak.When you put the bowl on and it don't fill up don't worry it will when the carb float opens up.Be sure the glass bowl rim has no chips in it.
 

[pinball]

your shut off valve is higher than the bowl. gas doesn't leak up. just down
 

[Caroline Chamblin]

Thank you pinball. Gravity is my friend.
 

[Caroline Chamblin]

I will look at the screen tomorrow. Wonder why it's an offset hole instead of the center.
 

[deanostoybox]

The original sediment bowl for the N series tractors has a square hole offset to one side like the screen in your picture. The sediment bowl you have takes a screen with a round hole in the center.

N series screen and gasket

screen and gasket with centered round hole, 2"
 

[Tim PloughNman Daley]

First verify the glass bowl top edge is free of any old cork gasket material. If it doesn't seat square to the world, it may leak. The first sediment bulbs, p/n 9N-9155 were brass, and had the round fuel outlet port central as in your picture, and used a screen with a round hole centrally located on it too. These were used from '39 thru '43. You have the 2N-9155-A unit, released after the war (WWII)and no longer brass but port still central. The 2N-9155-B unit was released in early '46 now had the offset square port and screen changed as well. This is the unit that was used thereafter up thru the NAA Model. Usually a leaking sediment bulb is due to the valve stem seal being worn out. It is a $5 part and easily replaceable rather than the whole bulb unit. If your valve stem is OK, then two options are open. Either get a piece of the fine mesh screen and make your own with the hole central, or get a whole new bulb assembly altogether. Option #1 is the first thing I'd try. Always use the cork gasket, never rubber. If you replace the whole assembly, don't throw away the old one. A 2N-9155-A unit is a wall hanger for obsolete parts. One final point is that the 2N-B units had the knurled knob on the valve stem to OPEN 2 FULL TURNS for Main, and FULLY OPEN to access the 1 gallon reserve in tank. Always be sure to close the valve when shutting down the tractor.



WORN VALVE SEALS:


SEDIMENT BULB VALVE STEM ASSEMBLY:


ORIGINAL 9N-9155 BRASS FUEL SEDIMENT BULB ASSEMBLY:


SEDIMENT BULB VALVE STEM FUEL FLOW KNOB:


Tim *PloughNman* Daley(MI)
 

[Bruce (VA)]

Of the 4 8N's I own, 3 came here with non-oem sediment bowls. All leaked. You have a non-oem style bowl. You can keep fooling w/ it and you might get it to stop leaking or you can just buy an oem style & not worry about it.
75 Tips

 

[Bruce (VA)]

PS......

I stand corrected per Tim's post. Your bowl is oem.....just impossible to find parts for!
75 Tips

 

[Caroline Chamblin]

Thank you Tim.
I will get some screen material and make a center hole screen.
I knew about the fuel shut off from Dell years ago when he visited and helped me with this old tractor.
My valve looks like a wing nut and has no writing on it.
The top of the bowl is intact with no visible cracks and I can't feel any rough patches. It is weird to me that the cross section of the top looks like a shelf. Just a narrow mating surface to the cork gasket and then a step down as if an o ring was meant to sit in there. I know it's not though.
Thank you again,
Caroline
 

[Caroline Chamblin]

Thanks Bruce!
 

[tractorguy2]

Looks like you have
an Allis Chalmers strainer too me.
 

[Tim PloughNman Daley]

You can kill two birds (or more) with a new Sediment Bulb Assembly. You'd get the offset square hole screen, a Fuel Valve Knurled Knob marked; and stop the leaking. I normally suggest just replacing the valve stem but not in your case. Like I said earlier, hang the old unit on your shop wall as being an old, obsolete, OEM part. As usual, it is your tractor and you can do anything you want to it.

Tim *PloughNman* Daley(MI)
 

[Caroline Chamblin]

Hi Tim,
I would be happy to purchase a new sediment bowl. I will have to drain the fuel tank to install it, correct? I don't want to by a part that is worse than the part I already own. That already happened with the rotor for my distributor.
thanks,
Caroline
 

[HFJ]

yes, any gas in the tank will want to come out, so u want to drain it as well as possible.