Aux Fuel Tank on tire trailer

[nsogiba]

Hi folks, I'm in the process of refurbishing my 48x96 HF trailer that serves double duty as a home utility trailer and a track day trailer to haul tires, tools, fuel, jack, cooler, the usual.

During my last few track events in my stockish E92 M3 I found myself needing to refuel throughout the day to ensure fuel stayed above 1/4-1/2 to prevent fuel starvation. Never actually had any starvation issues, but still want to avoid it.

I found myself needing to leave the track during precious rest periods or lunch hours to find a gas station and refuel. During these times I found myself wishing I could sit down and relax, rehydrate, check tire pressures, review data, socialize with instructor and other drivers, etc. It's also annoying dragging around multiple 5 gal gas cans that I have to bring in the car to fill up at lunch and hope it doesn't spill or stink up the car.

Last night while dreaming about warmer weather I thought up the crazy idea of installing a smallish fuel cell on the front of the trailer tongue area, behind the toolbox but in front of the actual cargo area.

Old photo of said trailer:



Here's where I'm thinking of sticking the cell. Toolbox would have to move forward slightly to allow a stake side to be installed in the front as I still use this trailer for firewood, plywood and lumber, etc.



I'm thinking a 15 gallon aluminum cell with a top fill that can be easily filled with 93 while refueling the car. For some reason this one is advertised at a 17 gallon but running the volume calc I only get 15.

I would need to have a -8AN bung welded on other the side at the bottom, or on the actual bottom of the tank. The idea would be to have a separate small 5 gal gas can that you can fill as needed from the trailer and then refill the car. Doesn't make filling the car any easier but you don't have to leave the track grounds.

In terms of safety, I'd need a secure mounting system, a relief valve to let it breathe for temperature differentials, and a shutoff valve at the "drain" that can stand up to gasoline.



Thoughts? Am I crazy? Too much egg nog?

[roastbeef]

It’s a bit much unless you need a specialty fuel that isn’t available at or nearby the track.
There might also be DOT regulations you’re violating transporting fuel, double check on thay if that’s even a concern for you.

[DRLane]

If I had a trailer, I would 100% build in a 50-100 gallon tank with electric pump. Then convert to run e85.

[bigjae1976]

There are a couple of things...

A 30 gallon tank will add almost 300lbs in fuel when full. Make sure you have enough gross weight capacity. Fuel in the tank will slosh and affect control of the trailer.

A fuel cell will likely not work very well as an external fuel tank. The fuel will expand and contract with temp changes. The biggest problem you will have is when the temp drops. Fuel tanks will generally collapse under vacuum so you need some sort of pressure relief/vacuum ventilation system. It needs to be sized correctly!!!

The biggest risk is static control. Static is created whenever fluid moves. So you will need to make sure the system is properly grounded.

Pumps rated for gasoline are expensive. Make sure its rated for gasoline! Most are rated for diesel and kersone.

DOT regulates gasoline transported for commerce. So if this is for a business (for the tax write off people) then DOT and OSHA might apply - there's a materials of trade exemption for small non-bulk quantities. I think you'd be ok with anything less than a 55gal drum. Not sure if you have to put the red 1202 symbol on the tank.

[nsogiba]

The more I think about it the more I realize that a stationary tank on the trailer doesn't really gain me all that much. It prevents me from going back to the gas station but it still requires me to fill up a 5 gal can, when then is used to fill up the car, adding unnecessary steps. I think I'm going to stock up on the popular race style 5 gallon jugs and just fill them on the way to the event.

[bigjae1976]

Originally Posted by nsogiba

The more I think about it the more I realize that a stationary tank on the trailer doesn't really gain me all that much. It prevents me from going back to the gas station but it still requires me to fill up a 5 gal can, when then is used to fill up the car, adding unnecessary steps. I think I'm going to stock up on the popular race style 5 gallon jugs and just fill them on the way to the event.

I've already thought about this. IIRC, I would need to spend almost $1000 on everything plus the time to install and maintain. Any fuel savings could be achieved with using 5 gal cans.

The only advantage is you can take better advantage of price swings. If you could store away 100 gallons and you can time the market then you can safely make $.50/gal a year? The savings comes in if you can SAFELY store thousands of gallons.

For my E46, I take 4 5gal fuel cans and about a 3/4 tank to a weekend event. I might have to fill up 2 -3 cans depending on the event. I usually have 1-2 left over. You'd probably want 5-6 for a much thirstier E9X M3.

There is a hand pump for the racing fuel cans that is available. I've seen mixed reviews on these but this is the best one I've seen.

https://www.pegasusautoracing.com/pr...sp?RecID=30125

Or a funnel makes refueling faster since you don't have the hold up the can as long all though requires a little more effort.

https://www.pegasusautoracing.com/pr...asp?RecID=9659

[admranger]

Or just put one of these on the trailer and build something to hold it in place during transport?

30 gallon portable fuel tank

Transfer Flow makes a horizontal one with a pump but it's $2k-ish. They are the gold standard of fuel tanks for vehicles though. Had a 72 gallon one on my old crew cab diesel truck. 1000 mile towing range.
Transfer Flow tank

[Richbot]

Please make sure all of the combustion sources in your hosue are venting to the outside because you're clearly under the influence of something? CAbin fever? Something

5 gallon cans and a hand pump or a steady hand with the hose coming out of the cap are all you need. Don't overthink it. They're rectangles, so build a rectangle to hold 3-4 of them standing up, and voila, no more leaving the track for fuel during the day

Disposing of the cell when you're done will also be a huge pain in the ass. The cans can go to a new home or landfill if necessary, not so easy with a fuel cell

Or are you snowbound and just need something to do? I'll ship you my racecar fiberglass to refinish for a lot less than $1000 if you're bored

[rcracin]

I know we love to overthink stuff and make cool shit. In this case 2-3 jerry cans strapped to the trailer should suffice. I like proper jerry cans like the oem toyota ones.

[DRLane]

This is what i had in mind - https://www.ronstoyshop.com/shop/enc...r-mate-custom/

[bigjae1976]

Originally Posted by DRLane

This is what i had in mind - https://www.ronstoyshop.com/shop/enc...r-mate-custom/

The problem is the trailer has a 7000lb capacity. The trailer itself is probably at least 3500 lbs. 45g of gas is about 315 lbs. So you can barely carry a Miata and a set of tires or two. Probably need dual 5k axles.

Looking at the tank, I don't see a pressure/vacuum relief. I'm pretty sure that tank is a diesel transfer tank with a pump not rated for gas w/ ethanol. The lack of a PVRV on the tank is a dead giveaway that it is a diesel tank.

You can use a gasoline tank for diesel, can't use a diesel tank for gasoline.

[DRLane]

Originally Posted by bigjae1976

The problem is the trailer has a 7000lb capacity. The trailer itself is probably at least 3500 lbs. 45g of gas is about 315 lbs. So you can barely carry a Miata and a set of tires or two. Probably need dual 5k axles.

Looking at the tank, I don't see a pressure/vacuum relief. I'm pretty sure that tank is a diesel transfer tank with a pump not rated for gas w/ ethanol. The lack of a PVRV on the tank is a dead giveaway that it is a diesel tank.

You can use a gasoline tank for diesel, can't use a diesel tank for gasoline.

It’s not this trailer specifically, but the concept. Get a larger trailer. The 315 lbs isn’t what’s going to limit you to a Miata. If you need 45 gallons, it’s going to weigh what it weighs.

Point is the concept is possible. Go this route : https://gastrailer.com

Can handle Avgas which would be equivalent to also transporting auto fuel or racing fuel.

[SAMM3Y]

In good old California these days, motor sports stores aren't allowed to sell tuff jugs as gas containers anymore, not sure if this is a federal or a state law. They sell the jug as a "water jug" and then sell the hose and valve separately known full well of the consumers intent. I purchased a few for the track and have noticed the plastic valves and tops for the jugs seize on them to the point where I snapped one of thr valves off attempting to open them with pliers! Also Regardless of how "loose" I dare leave the top it's always a bear to remove to refill as is the cap of the hose. Has anyone else experienced this? I bought a reputable brand and they weren't cheap from a reputable store.. frustrating

[DRLane]

Originally Posted by SAMM3Y

In good old California these days, motor sports stores aren't allowed to sell tuff jugs as gas containers anymore, not sure if this is a federal or a state law. They sell the jug as a "water jug" and then sell the hose and valve separately known full well of the consumers intent. I purchased a few for the track and have noticed the plastic valves and tops for the jugs seize on them to the point where I snapped one of thr valves off attempting to open them with pliers! Also Regardless of how "loose" I dare leave the top it's always a bear to remove to refill as is the cap of the hose. Has anyone else experienced this? I bought a reputable brand and they weren't cheap from a reputable store.. frustrating

Have had lots of luck with the VP 5 gallon jugs and their little hose bender thing. I keep the regular cap on with the middle port sealed with plumber tape. Then at the track cycle the one cap w/ hose between the bottles as needed. I transport 10-15 gallons in the back gently resting against the cage bar. No leaks and no issues. I don’t test my luck and only refill at the last station about 15 miles outside of the track.

[leftfootbr8king]

I was going down the path of adding two aux tanks to my Trailex, one for ethanol and one for 93.

I bought 8 vp jugs for 200 bucks from the supply store at VIR instead and avoided any further headache.

[bigjae1976]

Originally Posted by DRLane

It’s not this trailer specifically, but the concept. Get a larger trailer. The 315 lbs isn’t what’s going to limit you to a Miata. If you need 45 gallons, it’s going to weigh what it weighs.

Point is the concept is possible. Go this route : https://gastrailer.com

Can handle Avgas which would be equivalent to also transporting auto fuel or racing fuel.

Could certainly be done!

Just make sure there is a correctly sized PVRV or two way valve for gas. That’s the only difference between a tank that is rated for gas vs diesel other than rubber seals.

Tanks are built to contain low pressure. If it is subjected to vacuum then the tank will collapse and it does not take very much at all. IIRC, it takes about 5inHg to collapse a 4 million gallon tank (1/2” steel at the bottom). Gas is volatile and vaporizes. As temps drop then without a vacuum relief the tank would come under vacuum. One case could be if you are going over a steep elevation change and the temp drops a lot.

Also if you leave the tank a 1/4 full, the rest of the tank will fill with vapor. When you go to fill the tank you could build pressure and cause an explosion.

Just make sure those things are considered. Most places will tell you…yeah you can put gas in it! But the correct answer is…yes you can put gas in it but it is not safely designed to store gas.

The indication to me is I don’t see an external vent. You can also retrofit a PVRV, there is a certain sizing based on flow rates I believe.

[Richbot]

Originally Posted by DRLane

Have had lots of luck with the VP 5 gallon jugs and their little hose bender thing. I keep the regular cap on with the middle port sealed with plumber tape. Then at the track cycle the one cap w/ hose between the bottles as needed. I transport 10-15 gallons in the back gently resting against the cage bar. No leaks and no issues. I don’t test my luck and only refill at the last station about 15 miles outside of the track.

+1 for the VP Racing jugs. The only jugs I've had in 20+ years of playing with cars that haven't been annoying. Mine are pretty old at this point, still kicking, including the hoses.

[roastbeef]

Originally Posted by SAMM3Y

In good old California these days, motor sports stores aren't allowed to sell tuff jugs as gas containers anymore, not sure if this is a federal or a state law. They sell the jug as a "water jug" and then sell the hose and valve separately known full well of the consumers intent. I purchased a few for the track and have noticed the plastic valves and tops for the jugs seize on them to the point where I snapped one of thr valves off attempting to open them with pliers! Also Regardless of how "loose" I dare leave the top it's always a bear to remove to refill as is the cap of the hose. Has anyone else experienced this? I bought a reputable brand and they weren't cheap from a reputable store.. frustrating

my jag "water" containers i use for offroading have a pressure relief valve you have to manually click open and it becomes easier to unscrew the lids from temperature fluctuation. the vents also help dump 5 gallons pretty quick.

[bigjae1976]

Originally Posted by Richbot

+1 for the VP Racing jugs. The only jugs I've had in 20+ years of playing with cars that haven't been annoying. Mine are pretty old at this point, still kicking, including the hoses.

The other thing is a 5gal jug is convenient and reliable. There are 15gal jugs, 30 gal rolling containers available but you have to pump from those containers...what if the pump breaks? Malfunctions? Leaks?

Which brings me back to using 5 gallon jugs. I am going to buy a manual crank pump on my next Pegasus Racing order. So I get the ease of not having to hold the jug while refueling and I can still refuel if the pump goes down.