So, what kind of tank do you get? That's entirely up to you. My first SVO tank was an aluminum box with a tank cap. Now I use a beer keg. It was free. It's always good to recycle!
Material: Definitely use either aluminum or stainless steel. Regular steel will rust and clog your filter or injectors. Aluminum is light and easy to fabricate. There may be a possibility of incompatability with SVO. If it reacts with food, it may react with SVO. Stainless steel is impervious to whatever you put in it, but what a pain to fabricate!
-Hot vegetable oil may melt the plastic after a while.
-You will use screws to hold a plate on the tank. They may strip the plastic and cause leakage.
You can have an aluminum tank welded pretty easily and cheaply. Stainless steel should not be welded with regular steel. It is expensive to have stainless welded.
Make sure your tank will have a vent. See the link at right for a source of tank vents.
Of course, your tank will need to have some way for you to put your SVO in it. You can have a 2.5" filler bung welded to your tank. Then, you can use a screw-on tank cap.
Beer kegs have a filler hole in the top you can use. You'll need to connect a filler bung to the hole with some large flexible pipe and clamps.
To take out the pressure inlet, first push down on the ball to release pressure. Some nasty old beer may come out. Find the thin strip of metal that goes around the inside of the cylinder where the tap goes. This holds the pressure inlet in place. Pull the strip out. Then, the inlet should slip right on out, leaving you a nice-sized hole for inserting SVO.
Now for the fabrication. Check out www.greasel.com for ideas on how to fabricate your specific tank. Generally, you cut a hole in your tank and affix a plate over the hole. On this plate, you will attach thru ports for your coolant, veggie, and your vent.
NOTE: If you use your stock tank as an SVO tank, unless it's brand new you'll need to take the tank out and clean it with solvent (kerosene, carb cleaner, etc.) to remove deposits left by diesel fuel. If you don't, you'll clog your SVO filter and possibly your injectors!
Materials:
Flare Tool, pipe cutter
3/8" NPT Tap
1/4" NPT Tap
10-32 Tap
1/2" Hole drill bit
3/8" Drill bit
#21 drill bit
Tank vent
Two brass 3/8" male NPT X 3/8" barbs
Two 3/8" female NPT X 1/2" barbs
1/4" male NPT X 3/8" male NPT
teflon tape or pipe dope
3/8" ID vinyl hose
5" X 12.75" Transmission cooler
ATV silicon
Four stainless steel small hose clamps
Flexible copper or aluminum pipe
3/8" Flare nut
3/8" Flare X 3/8" female NPT
Your hole should be just big enough to fit your transmission cooler inside your tank. Your plate should be larger, big enough to drill/tap holes thru the plate and tank all the way around. Place your large hole on the top of your tank. Minimize all chances for leakage. On a keg, it's hard to fit a plate just right. If you have access to 2 kegs, you can cut a plate to fit over your hole. If you plan on laying the keg on its side in the car, put your hole on the cylinder. If your keg will be upright, use the top.
On the plate, in the middle where it will fit over the large hole in the tank:
Drill 2 1/2" holes and tap 3/8" NPT threads (coolant).
Drill 2 3/8" holes and tap 1/4" NPT threads for vent and SVO sending unit.
***If you install a fuel level sending unit, follow the directions of the manufacturer.
Use pipe dope or teflon tape to screw in the proper brass fittings. Use 3/8" male NPT X 3/8" barbs for the bottom of the plate (coolant.) Once the coolant barbs are threaded into their holes, attach a female 3/8" NPT X 1/2" barb to each male thread sticking out of the top of the plate.
Use 1/4" NPT X 3/8" male NPT for SVO. Insert the vent on the top of the plate.
While holding down your plate on the hole so that it is centered, drill holes all the way around with a #21 drill bit. Tap 10-32 threads into each hole, both plate and tank.
Connect 3/8" ID vinyl hose to your tranny cooler and the 2 hose barbs. Use stainless clamps.
Using flexible copper or aluminum 3/8" pipe, insert your flare nut and flare one end. Attach a 3/8" flare X 3/8" NPT female to the 3/8" male NPT on the plate. Adjust the length of the flexible pipe so that it sucks SVO off the bottom of your tank, cutting a 45 degree angle to prevent vacuum against the tank wall.
Okay, you've finished your hole, plate, tranny cooler, and SVO sender. When you're sure you're ready, spread some red ATV silicon around the outside of the plate. Put 10-32 machine screws in the corner holes of the plate. Press it into place and gently tighten the corner screws. ATV silicon may ooze out the side. This is okay. Screw in the rest of the screws and tighten, but don't strip.