That's a good spot!
CK5
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1982 C/K 6.0L Caitlyn Mall Crawler (Interior time)
- Thread starter Babaganoosh
- Start date
Sense I sold the 85 c10 I have a left over efi tank to put on the passenger side to have 40 gallons.
Here is where it gets tricky and someone correct me if I’m over thinking this. My goal is to turn the truck into a overlander.
Im going to use the 2nd gas tank as an auxiliary to where I can pump into the primary tank. If the fuel pump goes out in the primary I can just “flip a switch” and use the 2nd as a primary feeding the engine. Then I can quickly flip the flow on the pump that goes between tanks for transfer and reverse the system thus still having 40 gallon capacity.
What do you guys think? I have been watching to many drag and drive videos along with overlanding.
Here is where it gets tricky and someone correct me if I’m over thinking this. My goal is to turn the truck into a overlander.
Im going to use the 2nd gas tank as an auxiliary to where I can pump into the primary tank. If the fuel pump goes out in the primary I can just “flip a switch” and use the 2nd as a primary feeding the engine. Then I can quickly flip the flow on the pump that goes between tanks for transfer and reverse the system thus still having 40 gallon capacity.
What do you guys think? I have been watching to many drag and drive videos along with overlanding.
I think you are over thinking it. If you have a fuel pump in ea tank that will provide the correct injection pressure, and flow just plum the two tanks into one feed with a check valve at ea tank. then you only need have an electrical selector switch to turn the pump in the tank you wish to run.
If you wish you can link the tanks with a manual valve, in case of fuel pump failure.
edit 40 gl only gets my burb @300 miles on a good day
If you wish you can link the tanks with a manual valve, in case of fuel pump failure.
edit 40 gl only gets my burb @300 miles on a good day
That is a much better way of doing it then my idea and cheaper. My regulator is on the firewall next to the booster. I can just Y off the feed line and boom done.
Good idea Wes. Just gotta make sure the returns are isolated in some way. You could use a factory style tank valve and just plumb the returns to it. That way your fuel pumps would work on a switch, and your returns would be a switch too. If you only run 1 fuel gauge, then the factory switch could switch between which level you're reading. Also could your Holley be made handle the I/O of dual tanks in some way?
I didn’t even think of the return….
Yes the Holley can handle the ins and outs of both tanks, I love the pro dash
A few ways of doing it, use the factory selector switch, 6 barb, or 3 barb, or use a transfer pump like I did.
The factory selector switch is rated at higher pressure but could limit flow if you ever add boost. Walbro pumps have built in check valves, so you would just need plumb the factory selector in, the one that has a return built into it as well, has 6 hose barbs.
Or Y together the pumps before the rail, and just use a selector to change what pump is running. Ideally that switch would also run a selector for the return line only, then it wouldn't limit flow on the supply and wouldn't be on the high pressure side either. But then you need to decide if you have one filter or two. One filter after the Y would work, unless it pumps debris into the other pump. EDIT: This option could be dangerous if the return selector failed and you end up returning fuel to the wrong tank at potentially high pressure.
A transfer pump works but you have to remember to turn it on or off or you can overfill the tank or burn up the pump, could be dangerous if forgotten. I actually had a friend make me a transfer pump controller that could read both sending units and shut the pump off if one was full or the other empty.
The factory selector switch is rated at higher pressure but could limit flow if you ever add boost. Walbro pumps have built in check valves, so you would just need plumb the factory selector in, the one that has a return built into it as well, has 6 hose barbs.
Or Y together the pumps before the rail, and just use a selector to change what pump is running. Ideally that switch would also run a selector for the return line only, then it wouldn't limit flow on the supply and wouldn't be on the high pressure side either. But then you need to decide if you have one filter or two. One filter after the Y would work, unless it pumps debris into the other pump. EDIT: This option could be dangerous if the return selector failed and you end up returning fuel to the wrong tank at potentially high pressure.
A transfer pump works but you have to remember to turn it on or off or you can overfill the tank or burn up the pump, could be dangerous if forgotten. I actually had a friend make me a transfer pump controller that could read both sending units and shut the pump off if one was full or the other empty.
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Hmmm, my truck didn’t come with dual tanks so I don’t have one of those selectors. If I remember right they are not available after market?
I might still have the GM one, I had replaced it a couple years before the transfer pump, genuine GM, but not sure if it still works from sitting in a box for 15 years.
My '79 k10 had the returnless style mechanical pump and ran this selector if you wanted to run one for suction and one for return or the 6 port that everything runs through. Just more wiring then maybe.
I think running two separate units is not safe because if one fails and not the other you could have a major safety issue.
Although I suppose the same thing would happen if you turned on one of the pumps and that switch didn't work, suddenly you would be returning fuel to a different tank at potentially high pressure, which could be a major safety issue.
With the 6 port GM one it either works or it doesn't, but there shouldn't be a safety issue assuming your connections are good.
Can you just run a single big suburban tank? Balances the weight better too.
What we did with my fathers dual tank system was use two 3 way SS solenoid valves, one NO and one NC. That way, they defaulted to the main tank when off, but when both switched, they would switch tanks. However, there is still a chance one could fail and create a problem.
40 gallon burb tank under the bed, eliminates the don’t t bone me saddle tanks and only one tank to deal with
Yes but I already have the tanks and trying to not to reinvent the wheel on this one. Although just like everything else on this truck it needs to be.
I really don’t want to cut into the bed and create a filler. This is also the same reason I don’t have huge shocks through the bed.
You could steal something like this from the c10 guys. I believe this one's made by LS fabrication: 
There's guys that do an exhaust tube filler from one saddle tank filler over to the other saddle tank so that basically one tank fills up first then overflows over to the second tank across under the floor. Eliminates filling from both sides of the truck.
Just seen there's places selling in bed filler neck setups too.
Just seen there's places selling in bed filler neck setups too.
I really think I want to go simple on this one sense I have a lot of the parts. As much as putting more weight behind the rear axle would benefit a lot I'm trying to get away from pushing the truck that much further.
As it is right now offroad it is a animal, I can do just about anything and feel safe. Any faster it needs caged for sure, even now if something happened it would be ugly.
As it is right now offroad it is a animal, I can do just about anything and feel safe. Any faster it needs caged for sure, even now if something happened it would be ugly.
The y'd fuel feed with the simple switched return line is easiest. Have the same tank switch supply the power to the return switch that turns on the pump.
As for what happens if the return switch fails, it would return fuel to normally open side tank. If the tank were full that would be an issue. Adding a link tube at the top would allow any over flow into the current use tank. Fueling might be hard to tell when tank was full.
As for what happens if the return switch fails, it would return fuel to normally open side tank. If the tank were full that would be an issue. Adding a link tube at the top would allow any over flow into the current use tank. Fueling might be hard to tell when tank was full.
I’m really unfamiliar with these tank selectors, I have never seen one or worked on one.
I should have my factory style selector valve laying around somewhere I think. I bought it new when I put the first 454 with the Sniper.
I can confirm the factory selector valve is capable of handling the pressure of a newer injection system, at least 58psi. Mine worked fine. I had found the pressure rating at some point and I feel like it was around 65psi. I don't know about flow.
I can confirm the factory selector valve is capable of handling the pressure of a newer injection system, at least 58psi. Mine worked fine. I had found the pressure rating at some point and I feel like it was around 65psi. I don't know about flow.
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Found a couple of useful pictures.
If I remember correctly the wiring connector is a Weatherpack style.
If I remember correctly the wiring connector is a Weatherpack style.
