Fuel tank with air tank under bed in 49

[jocww]

So now that I got my bed on, i need to figure out where to put the gas tank and air tank. My air tank is from ride tech and is the 5 gallon size. The gas tank I dont have. I am looking at this one from ebay https://www.ebay.com/itm/15-Gallon-T...9aPiFi&vxp=mtr its only 120 bucks. Where else can I put these, I would prefer not to have any in the cab or bed if possible.

The first 2 pics of where I tried it today, but I think I would like it farther in the back in the last pic where my uncle and my dad were looking at it.
Any suggestions or opinons are appreciated.

[e015475]

I have a 4 gallon steel air tank. It is mounted on outside of the driver's side frame rail just under the driver's door.

This is the gas tank installation on mine - it is a 2nd gen Camaro tank, but early Mustang tanks will fit as well. This one uses a low pressure pump feeding a swirl-pot that feeds a Walbro high pressure pump for the fuel injection.

There's several things to consider with the ebay tank your contemplating using-

-It would be a lot safer if it were a fuel cell. Doesn't look like that tank has any bladder.
-The fuel sender is 90 ohms The factory gauges are 30 ohms (assuming you're using factory gauges. Most aftermarket gauges will use the 90 ohm sender)
-There's no baffling or sump to prevent aeration of the fuel. You may experience fuel starvation with moderate cornering or braking when the tank is low on fuel.
-You'll still need to plumb a fuel pressure regulator, fuel pump and filter externally to the tank.
-The external fuel pump will be noisy. It doesn't bother me, but some people don't like to hear it.
-The tank is probably fabricated with aluminum sheet stock and TIG welded together. I'd be a little concerned about quality control and leaks in the welds. I'd also be concerned about what might happen to the tank in the event of an accident. I'd much prefer an OE tank that had some engineering put into it when it was designed. "Race Drift" in the item description makes my skeptic antenna go up.

You might find that when you add the cost of the tank, all the external components (pump, filter, etc) along with all the extra plumbing, it would almost be the same price as some of the aftermarket tanks that have the in-tank fuel pump.

Look at Tanksinc.com website. There's quite a few others too.

Good luck


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[e015475]

Almost forgot this.

That tank is aluminum. Around here the fuel has ethanol in it that can cause problems with aluminum components and galvanic corrosion.

I've used aluminum tanks and fuel lines in off-road cars for years and never had a problem - but some people have

[Matt_50]

X2 on outside of rail. I bet that would work great. I guess inside of rail maybe too... how were the 47 under bed tanks installed? They had plenty of room for those, so a air tank should have plenty of room.

[jocww]

I cant really do much in front of the pumpkin unless its above it as the frame is square tubed and is about 6in space in between the tubes and the tank is 8in in diameter and i have the power brake booster under the driver side.

[thunderjet]

If you are using a stock seat, the tank will fit on the floor behind the seat.

[jocww]

Got it mocked up, now figuring out how to mount it, I think I will do a belly skid pan type of deal.

Only way to do it, if I had the gas tank in the rear I wouldnt be able to put the air fittings to the tank.

[MiraclePieCo]

Originally Posted by e015475

That tank is aluminum. Around here the fuel has ethanol in it that can cause problems with aluminum components and galvanic corrosion.

Just a side note from someone whose career was in the wholesale gasoline industry:

Almost all of you should be using "clear" (ie non-ethanol) gas for your hobby cars that don't get driven daily. Ethanol is hydrophyllic - water loving - and absorbs atmospheric moisture into your fuel system - devastating for vehicles that sit idle for extended periods. Here is a web site to help you locate ethanol-free gas stations in your area:

http://pure-gas.org/

[jocww]

EO can you send me some under belly shots please?? Trying to see if I should use straps or maybe weld a belly skid plate and then mount directly to plate. I'm thinking 11guage or 10 guage flat sheet.

[e015475]

I turned the tank 90 degrees and mounted it to the frame rail under the driver's seat. Here's a sketch of where it goes...........



Here's a shot of the outside of the truck. The air tank is under the cab between the two of the running board brackets



The tank is tucked up pretty far and it is hard to get a good photo, so sorry this one isn't very helpful, but you can kinda see the bracket and I put an arrow on the tank so you might identify it



There's a couple of issues.........

Your 5 gallon tank is longer than a 4 gallon tank - it probably won't fit between the running board brackets on your truck. I paid $65 for a four gallon steel tank from Jet, so cost isn't too much of a factor, but you will loose some air capacity.

The four gallon air tank is meant to be mounted with the welded-on bracket facing downward, and there's a port location on the tank for a drain. When I turned the tank 90 degrees so the bracket sits on the frame rail, there's no port for a drain anymore. I had to weld a bung to the tank with a 1/8" female pipe thread to install a drain valve.

[jocww]

Thats pretty cool, yea mine wont do that. I was actually hoping for how you mounted the gas tank. Sorry I wasnt clear. But I do really wish I could mount the air tank on the side like you thats pretty trick.

[e015475]

Oops. Thought we were talking about air tanks.

No real good photos in my files, but here's a drawing of what I did



The gas tank is hung in the chassis between two 2x4 cross members - I wanted a perimeter of steel around the tank in the event I get rear-ended. The front cross member is about 3/16" wall, while the rear one is about 1/4" wall

I bent pieces of 10 or 11 gauge steel to make the straps, and terminated the end with reinforcements I made from 1x2 steel tubing. IIRC I plug welded the strap to the tube, then followed up by TIGing all around the perimeter to have a lot of weld area in shear. Four 5/16" bolts hold the tank suspended under the brackets. After the bolts are tightened, there's about and inch gap between the top bracket and the strap bracket.

Hope this helps.

[jocww]

Awesome thanks. Is there a reason why you and most people use straps to hold the gas tank in, instead of building a floor out of flat sheet and just sitting it on top of that with some rubber grommets?

[e015475]

I did it the way I drew it because that's the way a lot of factory gas tanks are installed. I imagine that it was done that way to facilitate easy installation with the least amount of parts at the factory. A factory tank like mine is also designed structurally to be supported with a strap, and I'm not too keen on second guessing an automotive engineer's successful design.

I see you're in California, so it may not matter so much, but I'd hesitate to have a tank sit on a plate where moisture could potentially form and cause corrosion issues.

Hanging it like I did also means I can take the tank for service out by undoing two bolts and a fuel fitting.

I suppose you could design a floor that dropped out from below too, but it seems like a lot of unnecessary work to me. But you know what they say - opinions are like a$$holes, everybody's got one.