Fuel drain for MEP 803A

[jaybird67k]

Looking for an original fuel petcock drain assembly. I took the OEM one out that wasn't leaking and put in the "upgraded" version and it leaks.
Any help would be greatly appreciated.

Thanks, Jason

 

[2Pbfeet]

Are you looking for this item?

Brass Bulkhead Fitting 1/4" FPT I.D w/ 3/4" Required Tank Hole Size

Buy Ace Roto Mold Mfg. Brass Bulkhead Fitting 1/4" FPT I.D w/ 3/4" Required Tank Hole Size - 10897 from Farmer Bob's Parts and Supplies starting at 16.95.

farmerbobsparts.com

If so, I can confirm that the ones I purchased came with viton o-rings. Note: these are the bulkhead fittings with flats on the threads for a wrench to make installation easy.

All the best,

2Pbfeet

 

[Light in the Dark]

Looking for an original fuel petcock drain assembly. I took the OEM one out that wasn't leaking and put in the "upgraded" version and it leaks.
Any help would be greatly appreciated.

Thanks, Jason

So you are looking for the brass drain, or the well nut? There are a number of low end copies of the 'ultimate well nut' that are on the market, that should be considered poor replacements. As 2Pb calls out, the right one has an O ring groove in the rear face of the bung assembly, and includes a correct Viton gasket.

The drain should be carried over and should work OK in the ultimate well nut, unless its been OVER tightened. That can/will cause the proper one, to leak.

Can you share which one you installed?

 

[jaybird67k]

The OEM one didn't have a o ring it worked by internal expansion. The one I purchase from a member on here that has a eBay store is a o ring style.
This is what was in it.


This is what I purchased that leaks.

 

[2Pbfeet]

The original style rubber expansion well nuts have had issues for many folks. The replacement model bulkhead fitting that I posted above has worked for me. As it is brass and viton, it should be relatively unaffected by diesel and oxidation.

In principle, the solid brass fittings should seal better than the expansion versions, but both will be affected to varying degrees if the hole in the wall or interior surface are not clean or flat. The ones that callmecolt sells should work, but I have no experience with them. I prefer the ones from vendors such as Rotomold/Farmer Bob's and others, because of the flats on the threads make it very simple to tighten the bulkhead fitting to a reasonable torque from the outside. The best ones have a groove to retain the o-ring. I believe the McMaster-Carr versions have the groove, but it has been a while since I bought them from McMaster-Carr.

With the strainer removed, it is a five minute operation or so, with a 24-36" piece of wire, and a string attached to the wire. (Remove the old fitting, push a wire through the hole to the filler, put the bulkhead and o-ring fitting on the wire, bend a small "L" or "U" in the wire away from the bulkhead threads, and tie a string to the "U", pull the wire and the fitting into the hole, thread the retaining nut on, use the string to pull the wire out of the tank, and then tighten the nut to the bulkhead fitting. Done.) I think that the exterior flats make tightening the fitting simple and easy.

All the best,

2Pbfeet

 

[Light in the Dark]

I think the O ring groove is key to sealing, which is why I would recommend the original 'ultimate well nut' upgrade. With the O ring in the groove, the sealing gasket is much more prone to properly sealing (where the ungrooved item, the gasket can distort for the reasons mentioned above. Plus the actual shoulder of the well nut is round (same profile as the Viton gasket), so its just a better part to me.

 

[FarmingSmallKubota]

Are you looking for this item?
View attachment 944548

Brass Bulkhead Fitting 1/4" FPT I.D w/ 3/4" Required Tank Hole Size

Buy Ace Roto Mold Mfg. Brass Bulkhead Fitting 1/4" FPT I.D w/ 3/4" Required Tank Hole Size - 10897 from Farmer Bob's Parts and Supplies starting at 16.95.

farmerbobsparts.com

If so, I can confirm that the ones I purchased came with viton o-rings. Note: these are the bulkhead fittings with flats on the threads for a wrench to make installation easy.

All the best,

2Pbfeet

I use this part on all the MEP 531a's that I sell. Replaces the well nut on the fuel drain just like in the 802/803 they work well, but always need to remove burrs and prep the surface
Lets make this easy here is a link to the discussion about the well nut

Ultimate well nut repair

802a. I couldn't bring myself to fix junk with junk, not on my machine. Maybe a grass cutter.Nitrile or not those things are doomed. This even comes with a viton o-ring. Here is the permanent fix. $10.99 + S/H You do need to remove the fuel filler so you can get your arm in the tank. I was going...

www.steelsoldiers.com

 

[jaybird67k]

The problem with the new style on my tank is the hole placement in the tank. They missed the mark and it's on the part of the tank where it begins to curve at the bottom. So the o ring is having a problem sealing so I want to go back to the old expansion type that was sealing in the first place. I don't think it's a part problem as much as the hole in the tank isn't flat. I can find the rubber expansion piece but not the screw that goes in it.
I wish I would not have threw the old one away.

Thanks, Jason

 

[Light in the Dark]

Ive got some grey new style expansion, PM me your address.

 

[Light in the Dark]

And I think I have a valve assembly off a skid of an 802 (think its the same as the tank drain on the 803, I will reconsult the TMs)