Hey all, Recently ordered a stainless pump-to-carb 5/16" fuel line from JC that came with compression fittings. Well, I got curious and started cross referencing with 1941 and 1954 Master Parts catalogs which show only unbent 5/16" copper tubing and compression fittings for this year. JC and others claim their standalone fuel line (steel or stainless) to be "100% authentic in appearance, application and fit" with "proper fittings," yet they also sell a combo fuel-&-vacuum line set that uses compression fittings for the fuel line. So what actually came off of the factory floor? Steel and compression fittings? Was the copper tubing only to keep things simple for the dealers and avoid having to ship and store an array of pre-bent lines? Or were the originals actually copper?
And a related question: are the two 7" flexible fuel/oil lines listed in the Master Parts catalog for either end of the tank-to-pump line, or for something else?
Thanks!
(P.S. - I understand the concerns about using pure copper lines. There are good alternatives that still look the part. Trying to nail down what was original first so I can decide the most authentic looking and safe replacement next. I want to keep original where I can, and settle for "original looking" where I have to.)
Hy Backets, welcome, all I can say for sure is in my experience I have never come across anything but steel tubing for fuel line, I have seen it in both compression and inverted flare types. When I was taking my apprenticeship, we were told not to use copper for fuel line as it would harden and eventually crack when used for gasoline transfer.
I would bet the unbent line was for replacement use only, the original was likely pre-bent steel. You wouldn't have time on the assembly line to bend and fit lines as the truck moved along the line. Compression fittings don't seem right either, not sure I have ever seen a factory compression line other than the 1/8" brass oil pressure gauge line. I have purchased a a number of Carter Carburetor cores and all of them had inverted flare fittings for the fuel line. The rubber lines are for flex joints such as engine to frame, and tank to frame.
I have seen only steel inverted flair on all the GM trucks, although I haven't worked on anything older than my '57. My '55 International Harvester has steel line with compression on both ends but it's gravity feed from the tank to the carb.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
Every original fuel line I've see was steel. Mostly on AD and a little later trucks.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
Welcome to Stovebolt Backets. I agree with the rest of the guys that original factory fuel lines for your '41 were most likely pre-bent steel and the materials for replacing them at the time in the Master Parts Books were just the easy way out for making up replacements when needed.
I did a bit of snooping through various resources and found nothing that specifically states that so far. Even the original 1941 Chevrolet Truck Data PDF from GM doesn't discuss fuel lines. The specifications of the 1941 Truck fuel system are in the first pic below, taken from that PDF.
On your related question on the flexible fuel/oil lines listed in the Master Parts Catalog, the same hose assembly (GM# 592818) is used for both the flexible fuel line attached to the fuel tank output shut-off valve that connects to the fuel line going to the pump and on 1934-39 vehicles with oil filters as the inlet line. You only need the one for your truck for the fuel line connection. It's also my opinion that there should only be one (1) flex fuel line for your truck. The catalog shows a quantity of two (2) in the Parts Group 3.163 section (see 2nd pic) for some unknown reason, but later in the catalog under the truck specific Parts Group 16.000, it's listed as a quantity of one (1) (see 3rd pic).
Just IMHO, but I would go with the pre-bent steel lines as I think you will find them accurate in appearance and design and definitely the flex fuel line assembly..
~ Dan 1951 Chevy 3 window 3100 Follow this story in the DITY Gallery "My Grandpa Carl's Truck and How it Became Mine" 1966 Chevelle (Wife's Hot Rod) | 2013 Chevy Silverado (Current daily driver) US Army MSG Retired (1977-1998) | Com Fac Maint Lead Tech Retired (1998-2021)
Inline Tube does an excellent job. I've used their pre-bent fuel lines on numerous vehicles. They're always a perfect fit.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
I agree with the rest of the guys that original factory fuel lines for your '41 were most likely pre-bent steel and the materials for replacing them at the time in the Master Parts Books were just the easy way out for making up replacements when needed.