MEP-002 fuel boss/bung replacement?

[pebble41]

I am looking for a replacement part for the part that allows you to thread the water drain into the bottom of the fuel tank on my MEP-002. I believe the part is called the fuel bung or fuel boss but I am not sure. I sheared the fuel petcock off trying to remove it for my initial cleaning (It was packed full of sand and I was too stupid to unsolder it and wash it in the sink.) and then I broke the tap off trying to put a new set of threads in. I know that complete tanks are rarer than bigfoot, but does anyone know if there are off the shelf replacements for the bung and/or petcock? I'd like to keep the unit as close to "stock" as possible but if that is not an option I could live with a functional solution. The tank is in great shape so I really want to avoid just soldering a patch on. My current plan, if I can't find a replacement, is to try using some sort of small diamond tipped drill bit to remove the broken tap. Everywhere I've looked online wants to sell a weld on bung for a motorcycle tank. Thanks for reading. Attached is a picture

 

[Isaac-1]

Check ebay for mep-002 parts I think someone had these listed a couple of months ago

 

[Ray70]

To get the old tap out, they make a 2 prong extractor that fits into the space between the flutes of the broken tap and lets you unscrew it.
Maybe you could fabricate something similar out of an old socket with a couple pins welded to it, or cut away the socket and leave 2 or 4 small pegs remaining that will fit between the flutes.
Another option might be to shatter the remaining piece of tap. They are hardened steel, so a couple well placed hits with a sharp cold chisel will shatter it. Maybe even a slit with a dremel and cut off wheel to initiate a crack at the base of one flute?
Just gotta be careful not to damage the fitting.

 

[Keith_J]

I've use the broken tap with small welding rods to join the flutes, then wrap a screw type hose clamp around the tap and rods to remove. Taps are hard but brittle, steel welding rod is tough yet ductile.

 

[storeman]

Get a hex head grade 8 bolt of much smaller diameter (perhaps 1/4") and take it to a welding shop and have them weld the bolt to the tap. Not a difficult TIG weld. Use a box-end wrench on the bolt and carefully back the tap out.
Jerry

 

[pebble41]

Thanks for the advice. I'll let you all know how it turns out.

 

[bigbird1]

A welded on nut works too. Just put it over the tap and weld the center to the tap and turn it out. A faster way is to heat the tap with a torch and just blow it out. If you can't find anyone send it to me and I'll get it out for free. just Pm me .

 

[Keith_J]

Yeah, forgot about annealing the whole mess. You will need to prevent loss from mill scale, either stainless steel foil or packing in bone meal. Heat to 1600 F, hold an hour and then slow cool. Should render the tap machinable with HSS bits.

welding a nut to the tap will partially anneal it.

 

[Munchies]

What is that again 3/8 or 1/4? npt?
I would be tempted to Cover the area with a piece of 1/8'' steel , and then drill a hole and weld in a regular bung like this http://www.pacificcustoms.com/mm5/m...Product_Code=bungpipe375a&Category_Code=bungs

 

[Keith_J]

Yes, machining a new bung would be a snap, especially out of arsenic brass or admiralty metal for utmost corrosion resistance. A snap if you have a lathe. But broken taps are easily removed, either with tools or heat.

 

[Munchies]

Im waiting for someone to make a REASONABLY priced aluminum tank. Or I need to find a shop with some available time on a laser and cnc press brake. I get sick and tired of cleaning rust MEP tanks lol.

 

[Keith_J]

Aluminum is no better when bacteria colonize and make their nasty slime. Prevention is key, this means not storing fuel more than a year.

polyurethane tank coatings work, once you get the gunk out. That is what I did to mine, it has been three years without issues.

 

[Keith_J]

Im waiting for someone to make a REASONABLY priced aluminum tank. Or I need to find a shop with some available time on a laser and cnc press brake. I get sick and tired of cleaning rust MEP tanks lol.

No need for all that, just cut ends from 12 gauge aluminum and wrap 16 gauge around it, then weld with GMAW. Weld the long seam from the inside as a lap on the outside to prevent crevice corrosion, then inside corner join weld the ends on, replicating the original end seams.

you will have to find the fittings and weld those on. All you need is a bandsaw and hand shears. Marine grade aluminum is best, 5000 series.

 

[Carl_in_NH]

A machine shop with an EDM can burn the tap out for you, too. Works well.

If it were me, and I didn't have a lathe handy, I'd just cut a slice of round brass or steel stock of the correct diameter, drill the 4 mounting holes and the one center drain hole and tap it. Would take longer mounting screws, but it would work and doesn't require access to anything more advanced than a hacksaw, file, drills, and a tap.

 

[pebble41]

By way of an update, my dad (it sits in his back drive) got to it before I did and he was able to cut the tap out with dremel tool. I drilled out enough of the remaining brass to use a dental pick peel out the old brass threads. I have all the details and threads somewhere but it has been so long I'd need to hunt for them. If anyone wants the details let me know and I'll find them. I put it back on the tank and it held fuel over the winter so I think I'm good. I'm just now getting it running so I'll watch the first couple of tanks to make sure. Thanks again for the suggestions.