Mark L

What are the differences between a "standard" mechanical fuel pump for a Studebaker V8, such as a 259 or 289, versus a mechanical fuel pump for an Avanti R1 289? Is the flow rate and/or output pressure higher on a R1 pump to accomodate the Avanti's fuel return line to the gas tank?

I didn't do any work on the gas tank itself, so I can't give any advice on that. Neil Loughlin posted a series of videos on You Tube where he works on an Avanti. In one video, he describes the steps he completed to remove and clean the gas tank. That may be useful for you. The fuel hoses are pretty basic stuff. The vent hose is the most difficult due to its route. It goes through a rectangular channel and up into the right pillar between the rear window and the right vent window (directly opposite from the filler neck in the left pillar), makes a 180 degree turn, comes back down through the channel into the gas tank compartment, then goes down through a hole in the tank shelf in front of the right side of the tank. It apparently has (or should have) a clip that holds it up in the pillar. The hose passes through two holes going up through the channel and another two holes going back down. In a nutshell: I cut the ends of the old hose that were visible below the channel and pushed it and the clip up into the pillar. I will remove them in the future when I remove my interior for restoration. I'll put the clip on the new hose at that time. I straightened out a wire coat hanger and fed it through the inside of the new replacement hose. I tied an additional piece of aircraft grade .032 stainless lock wire to one end of the coat hanger wire. The coat hanger wire was sticking out one end of the hose, and the .032 wire was sticking out of the other end. The junction where they tied together was crimped tight to fit through the interior of the hose. I bent the end of the coat hanger into a hook and fed it through the holes in the channel so that it formed a guide for the hose. I beveled the end of the hose to make it easier to pass through the holes in the channel. I put some oil on the outside of the hose at the beveled tip to help it get through the holes. I put some oil inside the hose to make it easier to remove the wire once the hose was installed. I pushed the hose up through the forward holes in the channel while I was holding onto the coat hanger wire where the wire came out of the rear channel holes. The hose went up through the holes, was forced to make the 180 degree turn by the wire, and came down through the rear holes (after a lot of pushing and coaxing). When I saw the hose coming back out, I grabbed it with a pair of needle nose pliers and pulled it down the rest of the way as I fed more hose up into the pillar. Once I was sure I had enough hose to connect to the vent tube, I pulled the wire all the way out of the hose, cut off the beveled tip of the hose, and clamped the hose to the vent tube. I then adjusted the amount of hose in the pillar to make sure I had a tall loop that was higher than the filler opening on the left pillar. I then fed the hose through the hole in the bottom of the tank shelf. It took three tries to be sucessful. Adding the .032 wire and lubricating the hose were the two things I learned between the start and end. Ok, I guess that was a pretty big nutshell.

Earlier this week I replaced the plug in the T at the fuel pump outlet with a nipple, replaced all the rubber fuel hoses including the tank vent hose, and installed a check valve in the return line to the tank. I did not install the ball valve I purchased. I would have had to engineer a place to install it, which would have taken longer than the time I had available to work on it. The car had already been sitting on the driveway for the last month under a cover, so I needed to get it fixed and out of the weather. I should probably write a technical article for the Avanti magazine describing how I replaced the vent hose. I looked in the article index that was printed in the 2024-2025 member directory, but didn't see anything that described how to do it. That was the most difficult and time-consuming hose to replace. When I finished, I refilled the tank with 5 gallons of gas and leak-checked all the lower hoses. I then drove to the gas station to top off the tank to verify all the upper hoses were not leaking. Everything was dry. Now I just need to install the bulkhead and rear seat.

Yesterday (February 17, 2024) I attended the North Puget Sound Chapter SDC monthly meeting/lunch. I drove my '63 Avanti R1. After the meeting, I drove to a local farm/feed supply to buy ethanol-free gas. In the 11 months I've owned the car, I've put gas in several times, but never actually topped off the tank. Yesterday, I decided to top it off to make sure the gas gauge is working full-sweep. It turned out to be an exciting/frustrating fuel stop. While I was pumping, several people came by and mentioned something was leaking at the front under the engine. It has leaked a little anti-freeze in the past. Without actually being able to see while I was pumping the gas, that's what I assumed it was. When I finished pumping, I went to the front and found a strong, steady stream of gasoline streaming down near the power steering pump and fuel pump. I opened the hood, and saw gas coming from a short hose that looked like it was disconnected next to the fuel pump. The end of the hose still had a hose clamp on it. The supply to the pump was connected, so I assumed it was the return line to the tank. I was able to start the car and move it away from the pumps, and it never hesitated, so I knew the supply line was not sucking air. I got the car off to the side, but gas continued to stream out. The store had one bag of oil-dry at the pumps, and I used all of that. The employees went to find several more bags, which we used. I initially tried to fold the short hose over, but it was so dry-rotted it just snapped in half. They had no tools, but there was a hardware store across the street. I went there and quickly bought a ratchet set, some fuel hose, and some clamps. I then removed the old rotten hose that was disconnected and replaced it with a much longer hose, and I folded the end over and clamped it off. I ended up losing almost as much gas as I purchased. I called my wife to come to the station so she could follow me home. In the photograph she took, you can see the stain on the pavement I left behind when I moved the car from the pumps to the side of the parking lot. I called the county's non-emergency number and requested a fire truck come down to the store to stand by, just in case something worse happened. In the photograph, I'm laying in the mess under the front bumper with gas running down my left arm to my armpit. The store employees are to the right, keeping the spill contained until I could get it stopped, and three of the fire engine crew are checking out my Avanti. The leak stopped on its own before I capped off the open line, so I suspect enough gas leaked out to stop the flow. I was able to drive home with no other problems. Without thoroughly checking, I suspect that either the hose just came off the return fitting at the outlet side of the fuel pump, someone forgot to install the hose the last time the fuel pump was changed, or the fitting was changed and there's no place for the hose to connect any longer. When I topped off the tank, the gas must have overflowed down the return line back to the engine. Now I have some fuel system maintenance to perform. To be safe, I left the car parked on my driveway until I can get the issue resolved.