DontPanic42
Adventurer
The second tank has a fill neck same as the Mitsu tank. I have two ball valves, one on each tank, so that they can be isolated from each other when filling. I'll check to see if I have a photo that I can post.
my fg/camper pre purchase plan "101"
- Thread starter Gold Boy
- Start date
DontPanic42
Adventurer
Brent,
Never moved the original Mitsu tank. The extra tank was designed to fit in the space between the Mitsu tank back to where the fender is. We wanted to double the fuel load so that is why the aux. tank is taller than the Mitsu tank. That design is part of the reason that I have isolation valves on the tanks. There is enough head from the back tank that when everything is full up, fuel will push into the expansion area in the Mitsu tank and could leak out the top. I run with both valves closed until I reach about 1/3 full and then open up the rear tank. Makes me stop to turn the manual valves instead of just going, going, going... The 2 valve system also keeps you from losing all your fuel if you snag the fuel line. After trying flexible line, we replaced it with a rigid steel one. We also added some skid plates around the valves to protect them from being knocked off. A couple of rumen magnets that they use in cows were added to catch any wayward steel chips that might get into the tank.
You might want to use remote activated valves instead of manual ones like I used but I wanted to keep most things basic and somewhat fool proof. Of course gremlins can get into just anything. So far everything has worked well for me to date.
I haven't found any good shots of the setup so it looks as though I'll have to figure out how to use that digital camera a pretty lady gave me for Christmas. Of course my computer OS is just one step above bear skins and stone knives so even the new camera might not get the job done.
Hope this helps out.
Bruce
Never moved the original Mitsu tank. The extra tank was designed to fit in the space between the Mitsu tank back to where the fender is. We wanted to double the fuel load so that is why the aux. tank is taller than the Mitsu tank. That design is part of the reason that I have isolation valves on the tanks. There is enough head from the back tank that when everything is full up, fuel will push into the expansion area in the Mitsu tank and could leak out the top. I run with both valves closed until I reach about 1/3 full and then open up the rear tank. Makes me stop to turn the manual valves instead of just going, going, going... The 2 valve system also keeps you from losing all your fuel if you snag the fuel line. After trying flexible line, we replaced it with a rigid steel one. We also added some skid plates around the valves to protect them from being knocked off. A couple of rumen magnets that they use in cows were added to catch any wayward steel chips that might get into the tank.
You might want to use remote activated valves instead of manual ones like I used but I wanted to keep most things basic and somewhat fool proof. Of course gremlins can get into just anything. So far everything has worked well for me to date.
I haven't found any good shots of the setup so it looks as though I'll have to figure out how to use that digital camera a pretty lady gave me for Christmas. Of course my computer OS is just one step above bear skins and stone knives so even the new camera might not get the job done.
Hope this helps out.
Bruce
taller tank
Here's a photo Bruce sent me privately some years ago that gives a sense of the taller second fuel tank.
The standard tank is not taller than the top of the rear tire. The second tank is about as tall as the top of the fender, maybe 6 or 8 inches higher.
Bruce, is the second tank wider than the standard tank, or is it sort of oval, that is, taller than it is wide?
Incidentally, I have read several reports of travelers who had trouble with custom made fuel and water tanks. The custom tank welds developed small leaks after miles of travel over rough roads. So it might be best to find a tank from a commercial vendor, who would have better quality control over the welding process.
Chip Haven
Here's a photo Bruce sent me privately some years ago that gives a sense of the taller second fuel tank.
The standard tank is not taller than the top of the rear tire. The second tank is about as tall as the top of the fender, maybe 6 or 8 inches higher.
Bruce, is the second tank wider than the standard tank, or is it sort of oval, that is, taller than it is wide?
Incidentally, I have read several reports of travelers who had trouble with custom made fuel and water tanks. The custom tank welds developed small leaks after miles of travel over rough roads. So it might be best to find a tank from a commercial vendor, who would have better quality control over the welding process.
Chip Haven
DontPanic42
Adventurer
Chip,
Thanks for posting that picture. I may find the original again one of these days.
Anyway to answer your question, the tank I had built is 24" wide by 20" diameter vs. the 44" wide by 15" diameter for the Mitsu. tank. The clearance from the ground is about the same within a 1/2' or so. The added tank then is about 5" taller in diameter. Since it is not a pressure vessel, the ends are effectively flat.
Note: DOT requires that the fill neck be placed 15 - 20 degrees below the top of the tank. This provides a place for expansion of the fuel without spilling out the top. The actual useable volume is about 80 - 85% of the true volume. Somebody out there probably can quote the actual regulation.
Your point about potential leakers is a good one. My tank was rolled formed and welded by a local tank company. Unfortanately they won't do small tanks any more. My guys finished it off. They rebuild tank trucks and fuel tanks for 18 wheelers, oil field trucks and construction equipment. I am confident with their work but it doesn't hurt to watch for leaks in either of the tanks.
As an aside, the 4 guard cats (the stealth all black one is hiding in the shadows as usual) keep the mice, squirrels, possums and other various gnawing critters away from the camper. They work cheap and get to eat anything they catch.
Bruce
Thanks for posting that picture. I may find the original again one of these days.
Anyway to answer your question, the tank I had built is 24" wide by 20" diameter vs. the 44" wide by 15" diameter for the Mitsu. tank. The clearance from the ground is about the same within a 1/2' or so. The added tank then is about 5" taller in diameter. Since it is not a pressure vessel, the ends are effectively flat.
Note: DOT requires that the fill neck be placed 15 - 20 degrees below the top of the tank. This provides a place for expansion of the fuel without spilling out the top. The actual useable volume is about 80 - 85% of the true volume. Somebody out there probably can quote the actual regulation.
Your point about potential leakers is a good one. My tank was rolled formed and welded by a local tank company. Unfortanately they won't do small tanks any more. My guys finished it off. They rebuild tank trucks and fuel tanks for 18 wheelers, oil field trucks and construction equipment. I am confident with their work but it doesn't hurt to watch for leaks in either of the tanks.
As an aside, the 4 guard cats (the stealth all black one is hiding in the shadows as usual) keep the mice, squirrels, possums and other various gnawing critters away from the camper. They work cheap and get to eat anything they catch.
Bruce
Gold Boy
Adventurer
Carlyle said:
i once walked near a 5th wheel which was using Yamaha 1000, i could not even here until i was 20' away.... amazing!
cheers
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