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Discussion Starter #1
Does any one know what the flow rate is on the VE Pump return line to the tank. Here is what I want to learn;

Hook up a full 24 gallon tank to a 4B Series, and the return line from the VE Pump to a seperate empty tank. Head out on the road and drive the full 24 gallon tank empty. How much fuel approximate would have been returned to the seperate empty tank ?

Not looking for exact figures, close though

Thanks
Paul
 

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I did some messing around with this, it actually moves a lot of fuel through it. Not sure how long 24 gallons but my guess is at least a gallon a minute maybe?
 

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It would vary due to return line size, lift pump volume/pressure, injection pump calibration, and engine RPM. It's safer and easier to fill a remote tank using an electric fuel pump. You just need to incorporate an "overflow line" that returns the overflow back to the tank being pumped from. This line would be the same size as the electric transfer pump line. I also found out that you can't trust the fuel gauge on the remote tank whenever you trickle fuel into that tank. The gauge usually lags behind and the tank overflows before it reaches the full mark.
 

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Discussion Starter #4
Thanks for the replies. That shoots down my idea. LOL.

I am running dual 24 gallon fuel tanks on my new build. My idea was to send the return to only one tank to simplify switching tanks. I figured if the return flow was really small that it would just retrun to the prime tank. Since the flow is rather large, to much would be lost back to the prime tank. So I will just run returns to each tank and when switching tanks, flow/return is from the selected tank.

Paul
 

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If the tanks are mounted at the same level you could probably get away with running a 3/8" equalizer line that would connect to the bottom or near the bottom of both tanks. This would require the tank bottoms to be at or slightly above the bottom of the frame rails.
 

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Discussion Starter #6
BobS;

The prime tank is frame rail mounted the secondary tank is mounted in the bed. So I have to keep them seperate.

I have used selectable fuel valves in the past on Gas'ers that would accept 2 tank inputs and one output to the engine. I have never seen a selectable fuel valve that will handle flow and return for 2 tanks. Have you seen such a valve ? I perfer mechanical, electrics can fail.

Or, I will just use 2 of the selectable valves, one for switchable flow and the other for switchable return. Just have to be sure both are switched the same way. But since I am the Only driver that is not a problem.

Paul
 

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Paul,
I agree that the electrics can fail. The failure rate can be reduced by using a momentary switch with the center as the off position. I however have switched over to the manual types in "pairs" as you described. The last ones I bought came from Saturn Surplus here in PA: http://saturnsurplus.com/miscpage/fuelvalve.htm
If you have access to a milling machine these can be nicely mounted into a piece of square tubing without a lot of work involved. You might also check out their surplus Blazer Diesel fuel tanks which are priced right.
Bob
 

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Bob;
Thanks. Those valves are what I have used in the past and work well.
The tandem valves are the answer. I take my trucks to most remote regions and try to make tham as fail safe as possible. I even keep my engines bone stock for maximum Cummins Realibility. I already have the second tank installed. Pictures at;
http://imageevent.com/moosecreekmaple/m37project
The pictures of the 2nd tank setup are near the end of the album

Paul
 

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those valves definitely exist and are actually widely used by the guys running vegetable oil (SVO) conversions.. There are 6 port (two in, one out feed; two in, one out return) and then some people run two (or even three) 3 port switches if they want their SVO to bleed through at staggered times so are the SVO returns to the correct time, then they will also run a 3 port switch to either return to the tank, or loop back into the feed so they don't have to reheat new oil and can reach the desired fuel temps quicker...

I have been following the best kits I think are out there are plantdrive.com and frybrid.com , the plant drive guy is a guy a lot like us and rally helpful and I think their site/photos/descriptions/prices are better, and he will help you considerably with questions (Craig Reece). He has that badass custom Land Rover D100 with a 300TDI on vegetable oil, on http://www.roverhybrids.com/ He also has a very badass diesel converted 80 series land cruiser....

beer
 

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Nice work Paul. I now understand your project. My thoughts were you had frame saddle tanks installed.

Bob
 
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