fuel tank return line
 

needed a #8 fitting in fuel tank for my return, was told to drill & tap the sending unit, which I did, but not enough room between edge of tank anr elec part of sender, could get fitting in sender but hits tank, it's #8 w/3/8NPT on tank side..what have anybody else done for a setup like this ? thanks Rob

I make a setup similar to a sending unit. I use about a 2" hole saw and cut it out of a sheet of 1/8" aluminum. It will have a pilot hole in the center of the circle you just cut out. I open that hole up to the size of a #6 (#8 in your case) bulkhead fitting. I actually use a bulkhead fitting designed for fuel cells. It is a high flow fitting with teflon washers to seal it. I install that fitting in the center of my round plate. Drill 4 mounting holes around it. I then drill about a 1" hole in the tank (it's just larger than the OD of the bulkhead fitting) Then, using some self tapping SS screws, you mount it to the tank. I use a little piece of rubber and make a gasket. Works great.
It's hard to put into print exactly how I did it. I'm not sure if I explained it well enough. If you have any questions, feel free to give me a call. Good luck.
Eddie

Here is a pic. It's not very good, but it should help convey what I'm trying to say.
Eddie

thanks Eddie, understand perfectly !! just not sure about drilling in the tank !!! Rob

Cut your rubber tank fill hose, install a sleeve from steel or aluminum, weld your fitting in with a slight downward (toward tank) angle. Hose clamp sleeve back in and your done. Eddie's idea is more professional but drilling the tank would make me a little nervous!

Nothing to it. We use a hole saw to drill the hole. Just drill it very slowly and have someone hold a vacuum. That catches all the shavings. The piece should stay in the hole saw when you punch through. You won't get more than a couple of small shavings in the tank, if that. It won't make any sparks so there is nothing to worry about. I have probably done 25 or more of them over the years and have never had a problem. Never blew up either:drink:
Eddie

Yikes, I would seriously worry about the gas fumes entering the vacuum, the vacuum has plenty of sparks.

We are vacuuming the shavings before we ever punch through the tank.

If you have access, you can also tee into the fuel fill hose? I think the fitting is readily available.

can't even see my fuel fill hose....only access is from rear, it comes in front...