Sachs Fuel Tank - Adding a second petcock thread

Hi all,

Working on my first moped build using a Hercules Prima tank which I believe is the same as a Sachs Suburban tank. Wondering is there a correct way to add another fuel tap thread to the other side of the tank so that fuel doesn't get stuck on one side? The tank is originally meant to be upright and so this isn't a problem. The moped in the link seems to have done it but I can't seem to login to ask how he did it. Is it just drilled and then MIG welded on?

Thanks

https://preview.redd.it/oy1i9r1l6ql51.png?width=968&format=png&auto=webp&s=8046c2b6320e50e86963da26720c934e73d88f1c

[Garage Build: Seventy Eight\]

(http://garage.1977mopeds.com/build/Seventy+Eight)

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Re: Sachs Fuel Tank - Adding a second petcock thread

If you can weld, get a nut the same thread as the petcock and weld it on.

Or, get a piece of solid steel rod, cut, drill and tap it, and weld it on.

I grind an angle all the way around the bottom edge of the nut so it has a nice round channel for the weld pool.

Oh, and drill the tank first, file the hole and get all the steel chunks out.

Pretty simple if you can weld.

(Obviously clean the tank out, don't blow yourself up, safety first, etc...)

Re: Sachs Fuel Tank - Adding a second petcock thread

Dirty30 Dillon /

You can just braze in a pair of crossover barbs than you won't have to worry about using a second petcock, it will automatically balance itself.

Re: Sachs Fuel Tank - Adding a second petcock thread

Or you can just lean over a lot.

Re: Sachs Fuel Tank - Adding a second petcock thread

> baird co Wrote:

> -------------------------------------------------------

> Or you can just lean over a lot.

Ha . Not even a lot .

My Simplex has a couple gallon tank , divided down the middle by a 'wall' with holes toward the top . The petcock is on the right side . So , when it runs out of gas , there's always enough in the left side to get you back home ( provided it was totally filled to begin with ) . That after leaning the bike well over to the right , allowing fuel to the right side . ;)

Re: Sachs Fuel Tank - Adding a second petcock thread

I used a balboa tank as a toptank for almost a decade and it was never an issue, like at all. Like worst case I could envision, you could need to tip it to the side as a "reserve" but like, it's the last 1/8 gallon maybe that you're missing. I wouldn't worry about it

but if you wanted to, I'd just braze or weld in any barb. In fact the one time I did add a spigot I just welded in a barrel adjuster, cuz it's a hollow metal tube. that was easy.

I've also had good luck sealing stuff with JB weld including tanks, like big holes, so you could theoretically just glue a metal tube in each side, connect them there and be gtg.

Re: Sachs Fuel Tank - Adding a second petcock thread

Appreciate all the help with this, I'll give those ideas a go and see what happens. Only have a cheap stick welder and tens to blow holes in anything I touch with it so I'll avoid that.

I'll try the brazing or JB weld when the barbs arrive. Failing that I'll just lean the bike over, nothing like half a tank reserve.

Cheers all

Re: Sachs Fuel Tank - Adding a second petcock thread

Was thinking of using one of these on either side with a nitrile o-ring on the inside which I believe is petrol safe?

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Re: Sachs Fuel Tank - Adding a second petcock thread

Dirty30 Dillon /

How would you possibly fish it down inside of the tank?

Re: Sachs Fuel Tank - Adding a second petcock thread

I was thinking of using a piece of wire from a coat hanger, fed through the hole in the tank and out the cap and then through the barb so that the barb runs down the wire, into the tank and out the hole. Then secure from the outside. That was the plan anyway

Re: Sachs Fuel Tank - Adding a second petcock thread

use a piece of wire and fish that up through from the bottom til you can pull it out the gas cap hole, cuz that is much bigger and easier to aim for and see into etc. and then slid the lil bung buddy on down the wire

Re: Sachs Fuel Tank - Adding a second petcock thread

This is the perfect discussion to insert the `2nd reserve' info. on a lot of top-tanks.

Years ago I was within a coupla miles of Handy Bikes in Columbus, having ridden 100 miles of back roads to get there. I ran out of fuel on RESERVE near broad street.

I laid the bike on its side(motomarina Sebring) and picked up the bottom even more to get the last few ounces of gas into the tank on the PETCOCK side.

Upended her and made it to the gas station.

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