The Stovebolt Site Forums The Shop Area The HiPo Shop What Sending Unit For This Tank?

Can someone explain to me like I'm an idiot what I need for this gas tank (which is going in the rear of my '49 3100) to make gas go from it to the engine?

Here's the tank:
http://www.dormanproducts.com/itemdetail.aspx?ProductID=28453&SEName=576-329

I am assuming I will be using the fuel pump on the 235. In that case to I just need a ohm correct sending unit?

yes, the original fuel pump might work if the tank isn't too low, and you need a 0-30 ohm sender to run a stock gauge, a universal one should be available at a local parts store

Bill

Thanks Bill. What you say "too low", do you mean mounted too low, or too deep, or both? In any case the tank will be at least as low as the engine. Is that too low and, if it is, what's the solution?

not sure, but the stock fuel pump requires some "head" to suction dependably, if the tank outlet is below the level of the pump inlet much then as the fuel level goes down it may be "straining" to pull it that distance, they're better at pushing than pulling - I think those newer rear tanks all use an electric pump

Bill

So if I got rid of the pump on the 235 and use an electric pump, how does the line connect to the engine (if you know)?

Up to the Carb. From tank to pump, from pump to carb. Use a filter.
Wire from ignition switch to run the pump. You will need to make a block to cover the place the old pump was living in. Keeps the oil in and the dirt out. I would run the fuel line like the original as much as I could.

You're going to want the unit that goes in the tank. The original pick up for that tank was the bottom of the fuel pump. But you don't want to use that fuel pump because it would be way too much pressure for your carb. So you'll need to get a tube to extend to the lower portion of the tank. But, don't just use any fuel line hose to attach that tube. You'll need a hose rated for today's fuel that can remain submersed. OR, you can use a compression fitting. Otherwise, regular fuel hose will disintegrate. Somewhere after the tank but before the engine, the best option for you will be an electric pump. A low pressure pump. If you can't find a pump with low enough pressure, you'll need a regulator. If I remember correctly, pressure at your carb needs to be no more than 5-7 psi. Most original in tank pumps put out about 45 psi so you can see why you wouldn't want one of those. Oh yeah, at the pick up unit, you'll need to cap the return line as that won't be needed. But you'll only need to cap it on the top / outside of the tank.

This is what happens when you don't use the correct hose. http://www.bunchobikes.com/1952suburban141.jpg In my set up here, you would not use the fuel pump but you could use that return line that the pump is ty-wrapped to as your fuel pick up.

Oh yeah, you'll need to find a way to get a 0-30 ohm sending unit in there. If you look at my picture, you'll see where I made that hole / mounting for that fuel pump unit. You could do the same for a sending unit. Any sending unit you find that originally worked with that tank will be the wrong values for the stock gauge. Not a problem if you use a gauge that will match that unit. ( Upgraded dash, etc.)

Thanks for all the advice but now I am more confused than before. You say I need the unit that goes with the tank but two posts after you say I need a way to fir the 30 ohm unit in there. What do you mean?

Your certain I need an electric pump?

The hole in that tank requires the specifically shaped fuel pump unit that has the plate, "O" ring and locking ring. Otherwise, you will never seal that existing hole.

You'll only need the 0-30 ohm sender if you are using the stock gauge. Trying to mate a 0-30 ohm to that tank or that tanks stock pump unit would be quite a feat of engineering. You will understand once you have all the parts for that tank.

You might not need an electric pump, but that would be the easiest route. Otherwise you would be asking your stock pump to draw from a tank at the rear of the vehicle, all the way up to the motor. I'm not sure if a stock pump would be up to the task.

Are you looking for sending unit.(instrument for measuring gas level)? or fuel pump?( instrument for transferring gas from tank to engine)?

Apparently I'm looking for both.

Pretty apparent your title ask one question, and apparently you didn't know the difference.

What I mean is that other's now suggest I need both. But the fact that I'm fairly short on knowledge regarding all things automotive is, well, not exactly a secret.

No one says you have to use a sender ( and a gauge.) You could regularly put a stick in the tank to see the level or guess by how many miles you drive. But you won't go anywhere unless you pick up the fuel out of the tank.

We are all here to learn, but your apparent "remark" seems to borderline on being a smart "s". So will let it go at that, was only trying to get a clarification. These threads are quite often hijacked with no harm meant it just goes that way sometime.

I'm really not trying to be a smart [censored].

I need a sending unit so I can see on the dash how much fuel is in the tank.

I have a fuel pump on the engine but some folks are saying I need a different pump because the one on the engine won't work for this application.

So apparently (and to my surprise) I do actually need both.

But I'm no closer to knowing WHICH sending unit I need for this tank. If I need something proprietary for this tank and have to figure some way to rig an original sender to it, I mine as well just find another tank.

Or...?

here you go, done deal

will you need a new gas gauge ?
I used a s/w and sending unit to match from Napa,, my tank was behind the seat though... stock type

I've still got to see if the tank I have can be rigged to work.

$200 for a tank (without the sender or a pump) is too much for my budget.

Couldn't you use one of the frame mounted electric pumps and just put the sending unit and pickup in the tank. Just wondering, if it were me I'd want simple and easy.Larry

This is what I did. I used a tank from a 89 S10 Blazer, that is the same configuration as the one you pictured. I used the Blazer fuel pickup, threw away the electric pump and used one tube for a fuel pickup and blocked off the rest except one for a vent. I wanted to use the original 49 gauges so from the original 49 gas tank, I cut the sending unit mounting area out of the old tank and welded it onto the top of the Blazer tank, so now I can use the original 49 gauge and sending unit. With a voltage drop from 12v to 6v.Put a universal 4-7gpm electric pump close to the tank and your in fat city, assuming both your old gauge and sending unit are in working order.