How do I use the tank selector on 1973 Camper Special

[Arroyo083]

Thanks everyone. I’m currently using the “R” or what I think is positioned at the R.. so we’ll see if it’s using from the other tank now. The driver’s side that is. Hopefully everything works and I don’t need to pump 20 gal out haha.

 

[DoubleDingo]

looks like a push/pull stem rather than a twist left/right.

good luck!

It's a twist, not push/pull

 

[DoubleDingo]

I had one of these on Mean Green, but it was only a three port, no returns. It's a twist 180 degrees type of thing to select the other tank.

On Mean Green I ran the side tank as my main tank, and the seat tank as my auxiliary tank. Mean Green was a '65 C20. Anyhow, the side tank would make a sound when the tank would suck in when it was running out of fuel, this only happened on the open road though, and it allowed me to switch over to the other tank and keep going. I never had a working gas gauge in that truck, so I had my ways of figuring out the fuel levels and never ran out.

 

[Arroyo083]

Thanks everyone! I’m assuming everything is working. The middle, can’t see in the picture, shows an “M” that I didn’t see before. I assume that’s for main because it was using the passenger side tank when I had it positioned to that when I bought it. And sounds like everyone is saying the pass side is the original. I switched it to “R” and now it’s taking from the drivers side! What’s the best way to use these tanks? Because no matter what, the fuel gauge doesn’t work. It shows past full, off the scale, no matter what.

 

[Grit dog]

Use em however you want. But if they both work fine I’d use both interchangeably to keep fresh fuel in them and keep the valve operating.

 

[bucket]

Thanks everyone! I’m assuming everything is working. The middle, can’t see in the picture, shows an “M” that I didn’t see before. I assume that’s for main because it was using the passenger side tank when I had it positioned to that when I bought it. And sounds like everyone is saying the pass side is the original. I switched it to “R” and now it’s taking from the drivers side! What’s the best way to use these tanks? Because no matter what, the fuel gauge doesn’t work. It shows past full, off the scale, no matter what.

Since the aftermarket valve has no electrical components and the aftermarket tank has no sender (I'm assuming), your fuel gauge only reports what is in the factory tank. You will have to go through a diagnostic procedure to figure out what is causing it to read incorrectly.

 

[Arroyo083]

Thanks guys. New issue is gas is spewing out of the main/passenger side at the fuel neck/gas cap. I see it has a vent line on the neck to the tank… idk why this is happening. Maybe just a new gas cap? I feel like it was a lot one time.

 

[75gmck25]

If you have a fuel pump with a return line, and the fuel solenoid/switch only has 3 ports, you can’t switch both fuel feed and return (that requires a 6 port solenoid). This means you might be drawing fuel out of the drivers side tank , but the fuel will be returning to the passenger side tank. Eventually it will fill up.

 

[Arroyo083]

I’m so lost haha. If it’s going to the passenger’s side, no matter what, why is there a selector? That’d be great if I only had to fill one side and it all fills up and it just draws from one side, as if I just had a huge tank. But I don’t think that’s how it’s working.. man this is complicated.

 

[Bennyt]

I had a '72 in '95-96ish and it had 3 tanks(behind seat, and a R/L 30 gallon) with a similar switch on the floor. Mechanical fuel pump and the truck had to be running to switch to the side tanks or it would only pull from behind the seat.

As a side note, only filled up all 3 one time. New Union 76/ Unocal gas station opened and they had a sale with 99cent a gallon gas.

 

[75gmck25]

Arroyo083 - I think you missed the point of the 3 vs. 6 port solenoid, and how it fits with a fuel return line.
- two port fuel pump with no return line to tank. You only need to switch the fuel feed from one tank to the other, so the solenoid only has 3 ports (two lines in from the tanks and one line out to the engine).
- if you have a fuel pump with a return line to the tanks. When you switch the fuel feed from one tank to the other (as above) you also need to switch the return line from one tank to the other so that fuel will return to the same tank it’s being pumped from. This means the solenoid must have the same 3 ports as above, but 3 more ports to switch the fuel return line.

You want to use a fuel pump with a return line. It helps prevent vapor lock because when the float stops fuel flow and the pump has to return it to the tank, the circulation of fuel will help cool it down.

 

[SirRobyn0]

Another question. 73 wouldn’t have had return line from the fuel pump originally. But that’s a 6 port valve so must have a return line?

I know at some point the return line became standard equipment (80ish I think), but for sometime before it was optional. A friend of mine had a 1972 Chevrolet C30 350 TH400 single rear wheel. Though they didn't call them camper specials in those days (keeping in mind this was the last year of the body style before the square), this thing was made to haul a camper and from 72 until he bought it in the late 80's it was married to a camper. Anyhow that truck had a factory return system, at least I think it was factory. Unfortunately he beat it up pretty badly and eventually scrapped it, so I can't go look at it. But I did look it up and there is a three line fuel pump for that year truck listed. IDK maybe someone added it, but I always thought it was factory..... Anyhow some food for thought.

 

[75gmck25]

My ‘75 K25 camper special with a 350 has a factory metal fuel return line. I have HD cooling with A/C, and the camper special suspension upgrades, but no other unusual options.

 

[andybflo]

My ‘75 K25 camper special with a 350 has a factory metal fuel return line. I have HD cooling with A/C, and the camper special suspension upgrades, but no other unusual options.

I own a '69 Corvette, and '63 Impala.

Both have factory return lines; 3/8" Supply, 1/4" Return. So, that's not odd on GMs. Maybe it's odd on light trucks, but, I'm betting it's based on how the vehicle was optioned/type of carburetor/etc.

Low performance 409s, for example, on the '63 didn't have a return. Only the high-flow fuel pumps needed it. The Corvette had it for Rochester equipped motors, but not the Holley motors (the needle/seat can handle higher pressures is my guess.) I'm betting your camper special was outfitted it based on potential underhood temps where vapor lock could be an issue in a high-load/weight situation.

 

[oldretiredafguy]

Here are all photos I took! Thanks for the reply! It’s like 1st owner deleted that (your right) drivers side option. Idk if R means right or reserve.

This is an old 50's-60's 18 wheeler fuel tank selector valve. Probably still get seals for it from a true big truck parts store. Might also try NAPA, they carry a ton of parts for older stuff.