Hi all info needed..got a 1963 chevy pickup truck and it has three fuel tanks one original behind the seat and one either side under the buck with a diverter switch down by the drivers seat only details on switch are GEM TANK CLACKAMAS ORE ...see attach pic of switch....cant seem to find any info on this set up unless the company is no longer trading.....any help appreciated.....w.w.w.f
What info are you looking for? It's something that was made long ago, to add fuel capacity to the truck. The parts are just what you said they are. The Gem company is still around, selling camper shels.. The valve itself was probably a part you could buy from an industrial parts supply place. The tanks were probably fabricated by the Gem Tank Co., to fit a variety of trucks available at the time.
Hi thanks for the quick response didn't realise it was just for extra fuel capacity...running a big block so probably needed it ...many thanks
It appears you aren't a man of many words. Welcome back, what Jim says but I'll add that the M is for main tank, R for right and L for left auxiliary tank. Quite common for additional capacity especially if hauling a slide-in-camper in the day. Run down the road on one of the auxiliary tanks until the engine sputters, switch to the other auxiliary and run it until it sputters then switch to the main tank that is hooked to the fuel gauge...then fill up all three at the next stop.
Unless you are doing some long trips or working the truck, I’d pull the auxiliary/reserve tanks and plumb it off the main tank.
The additional tanks may have been added during one of the gas shortages back in the 70's when we could only get fuel on alternate days according to your odd or even tag number.
The company I once worked for had the exact set up in an early 70's Chevy truck. It was used when we had to plow snow. When the forecast was for snow we made sure all the tanks were filled as the gas stations would be closed because of the snow.
Damn, hasn't anyone except Jim, windup toy and myself ever seen an older truck with auxiliary tanks on it? As winduptoy said all you have to do is figure out what tank the truck is running off when you turn the handle in what direction. There is also one direction you can turn it to that shuts the gas off if the very similar valve that was on my 63 GMC was any indication. Back then there weren't any or many electric valves that you could switch tanks with as on the 73 and up GM pickups with dual tanks. There is no need to remove the Auxiliary tanks if you don't want them and there is absolutely no frigging way they will feed into the stock behind the seat tank without pumps to transfer the gas to the main tank so that just doesn't fly. Most of the time they were installed when the trucks were new and were either hauling a camper or towing a camp trailer and the 16 or so main tank didn't get you all that far without a fill up and the extra capacity extended your distance between fillups. Lothiandon1940 would probably wish he had extra gas out in Wyoming, Utah, Nevada or Idaho where often enough you see signs that say "Next gas 110 miles" or even more than that in some places. Get out in those places and turn off the main road and you can be 150 - 200 miles from a gas station real easy. Still if the auxiliary tanks are dry/empty and you have the valve turned to the main tank as you only plan to run off the main tank that valve is a nice way to keep anyone who may decide to drive off with the truck from getting very far.
No, many more than you three have had and have multiple tanks, but for a reason. I pulled the auxiliary tank from my OT truck when I decided it wasn’t needed. Does the OP need to have 60 or so gallons of fuel on hand at anytime? I guess he’d be the one to answer that.
Auxiliary tanks with a manual selector valve were very common around here in the 60s thru 80s, until pickup manufacturers started offering good systems. My guess is that although it has a name tag that says Gem Tank, Clackamas, Oregon, they simply purchased the valve from a supplier and put their ID on it. The valve is a basic design made by several manufacturers and readily available from parts suppliers (there may be the manufacturer's name molded or stamped into the body of the valve). Take a look in the McMaster-Carr online catalog to identify it, and go from there to source one. Good luck!
8-10 MPG on a BBC 3 tanks was needed, And even less MPG towing something.. It was quite popular for a truck to have 3 tanks out here on the left coast where towns was MORE than 50 miles apart and even further between gas stations.. Remember gas stations closed at 5ish or dark thirty and there wasnt no credit card access to get fuel after hours..
I bet this is his fuel valve... And the Installer just used there logo to look fancy instead of writing on the floor L R Main
Also one other side note.... One would use both saddle tanks FIRST, Then switch to MAIN and start looking for a gas station !
I had that set up on my main OT truck years back.It had two 15 gallon aux tanks and the original tank. I loved it. Like mentioned run the right out, then the left out, then use the gauge on the original tank! Great for traveling, I could drive through tThe high prices to lower priced gas. Just took a trip to Colorado last week from Muskogee, saw almost $1 difference in gas prices. Carrying over Fifty gallons, that could be a savings of near half a hundred. It’s was better than the new electric controlled fuel switches! Bones
One thing to add... give the saddle tanks a thorough inspection before filling them up with fuel if you haven't yet. Depending on how the truck has been used in the more recent, chances are the saddle tanks were not. I bought a '68 C10 with a similar setup to yours and one saddle tank had been empty for years while the other had about 6 gallons of 20 year old gas. Both stunk to holy hell and had all kinds of flaky deposits inside. No doubt had either of those tanks been filled and used, it would have caused some serious problems to the rest of the fuel system. With that setup in your truck, you could drive from Wales to Scotland! LOL
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