Brothers Trucks 1963-1972 Blazer/Suburban Gas Tank Installation

03/01/2016

Brothers Trucks 1963-1972 Blazer/Suburban Gas Tank Installation

03/01/2016

BROTHERS Blazer Suburban Gas Tank Kit is an easy-to-install kit designed as a direct replacement for the factory steel gas tank found on 1967-72 Suburban and the 1969-72 Blazers. This kit can also be used on the 1963-72 pick-ups. This requires adding a fuel line down the passenger side frame rail and installing a filler neck assembly as described below. On the pick-up trucks, the spare tire must be relocated and the spare tire bracket removed. Also, some vehicles require that a bed cross sill be trimmed for clearance. The tank is now reproduced in rust-free poly-ethylene for a trouble-free, long-lasting installation

Our 1971 Project Suburban has had a lot of previous modifications prior to us acquiring it. The vehicle had been equipped with a 45 gallon (yes, 45 gallons) steel plate fuel cell in place of the original tank. Removing this tank was a challenge in itself. The old tank was secured with 4 long 1/2″ bolts going directly through the tank and the hardware was rusty and difficult to remove. Not surprising considering the trucks previous use as a tow and launch vehicle for a drag-boat team. The vehicle has been converted from a 3/4 ton to a 1/2 ton and has been lowered 5 1/2″ in the front and 6 1/2″ in the rear. Now we had the ride height were we wanted it, it was time to regain some of the ground clearance by exchanging the hulk of a tank with the 21 gallon poly tank.

We were careful when removing the old tank because it was still about half full when it was being removed. This was because the sending unit that was in the tank went bad a few months before this swap and we always tried to keep a good amount of fuel in there. Pushing this thing is not a fun task. We lowered the tank enough to get to the fuel lines and filler hose connection. After these were removed and capped, we dropped the tank all the way down on the jack and set it aside. We did not use any of the components from the existing tank on the new unit because the tank set comes complete with the straps and a new AC Delco sending unit. The new sending unit mounts with a steel lock ring and a few screws.

To simplify the installation we also mounted a new 3/8″ fuel hose, vent hose, and the new 1 3/8″ filler neck hose with the new tank still on the ground and capped off the ends of all hoses to keep any dirt and foreign material out during installation. The tank has provisions for a fuel return line and an additional vent, we just plugged these with some 1/4″ brass pipe plugs with some liquid teflon sealant, like we used on all the tank fittings. We put the tank up into it’s location to check the fit and see if any holes had to be drilled for the attaching hardware. We found that the two holes originally use in the frame for the drivers side bolts where too close with this new style poly tank. We drilled two holes 1″ farther out on the frame rails to accommodate the wider flanges on the new polyethylene tank. With the straps bolted to the drivers side frame rail and the tank up on the floorjack (using a 4 x 4 to support it evenly), we fed the fuel, vent and filler hoses between the frame rail and the bed floor and connected the gas tank sending unit wire.

With the tank up and in place we started work on connecting the passenger side S-bolts. They slip into the elongated hole on the outer vertical area of the frame. The straps are a snug fit and require some patience to get started over the S-bolts. Once they are started over the bolt, a hex nut will hold them in place and allow you to tighten the straps. We tightened the straps up so they had even tension on them and double nutted the S-bolts to lock them in place.

After the tank was mounted we connected the fuel pick-up line to our rear mounted electric fuel pump and secured the clamps. The filler neck hose had to be trimmed to length along with the filler vent hose. With these cut to length, they were connected to the vehicles original filler neck and vent. This is where the pick-up truck differs from the Suburban and Blazers. The pick-up does not have a filler neck in the bed and most of the people we have talked to have opted to graft one into the bed side on the fleet side or hide it in the wheel well on a stepside. The parts are generally available from a trailer or full size truck (tractor-trailer) supplier. Ours was pretty simple with the existing filler neck, but we decided to remove the neck to have it painted and then reinstalled it. The hoses were then double check for tightness and the tank was filled.

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