EFI fuel return line

[skidoo29]

I bought a new plastic gas tank and It didn't come with a spot for a return line from my motor so I have to add one.

the question is, how do I drill and tap into the tank without getting a bunch of littlte bits of plastic inside the tank?????

thanks in advance

warren

[PaulR]

In the past I have pulled the sending unit and drilled and tapped that. I also have put a plastic fitting in the fill tube, both worked for me.

[T-REX]

Az U drill tha hole, hold a shop vac right at the bit, and go slow...it will suck 99% of the drillingz up in tha vac....Now, if U kan put the line return close to tha spout, U kan use a minnow net(bent to fit in the spout) to catch thangs that cumz from drilling...REX

[Techno]

I don't understand how your mounting something to plastic without getting inside?
I'm making a plate to do this, but with 3 fittings. A ring inside the tank and the plate on top. Gasketed so it don't leak. The inside ring is threaded to accept the screws from the outside plate.
With a hole large enough to put a thing like this in it's easy to wash out, speaking of which you can always spray water in the tank upside down and let the garbage drain out thellarge fill hole.

[Raceman]

Why don't 'cha just do it the easy way? Buy a Mercury water seperating fuel filter assy. It's got 2 ports on the inlet side. Mount the filter between the tank and fuel pump. Plumb the return line into the second port on the inlet side. That way the tank doesn't have to be drilled. Merc even put a diagram in the box with the filters at one time showing that plumbing route, but I've since bought one without the diagram.

[Gerben]

Flip tank upside-down and drill from below.
Junk on the floor and not in tank.

Gerben

[Balzy]

I could hear and on one boat see (Nick Kayes Euro) which had a clear plastic tubing on the return side of the regulator air was recirculating through the system. I dump mine back in the tank and the fuel pump runs nice and smooth again.

[Raceman]

Mike, I've run em that way for years with never a problem and all my stuff has dash mounted fuel pressure guages. I've never seen a dip in the pressure reading.

[Balzy]

Do you run the Bosch pump or a Weldon, or other? I run the Bosch and you can hear air gurgling through the pump when I pipe it that way. I also use huge lines. 7/16" ID on the inlet and outlet of the pump to the rail and 3/8 on the return line.

[NPK2003]

are the bubbles just an STV thing. Kind of like Dom escaping from it's perfectly chilled bottle at your dining table. The affect is similiar to NOS but uses only pure Oxygen suspended in the raw fuel as you already know Raceman. Guess that's why we STV's are twice as fast as Streams Mikey! We pack air under the hull and in the gas!!!

Oh Boy! Here come the Amigo Hats!!

Nick K

[skidoo29]

thanks for the help everyone, I still haven't decided what to do, but all your suggestions are greatly appreciated


warren

[stvhelm]

The water seperator didnt work for me either. I had the same simptoms as nicks. I drilled the tank with the vacuum sucking the shreads up and put a through hull fitting close to the fuel level sender for the return line. By temporarily taking out the fuel level sender you can get the nut on the inside to tighten up the fitting.