Trojan Boat Forum

on my 1978 f32 i have removed my aft only tanks and am having new aluminum tanks made. (unbeleivable amount of crap look like someone had been playing at the beach with all the sand like stuff in there.) since i am going to all this trouble should i replace my oem copper fuel lines? i have no corrosion (i am in fresh water also) all oem lines are intact with no problems noted. however they are 33 yr old. the tank will have female pipe thread bung fittings that i can use my original fittings or if i go hose just replace with barb. i did find that none of my antisiphon valves worked at all they were all stuck open(good or me it wasnt stuck closed)
i know i will need to use a stainless steel bushing as a (insulator) between my oem copper and the tank to prevent any disamiliar metal problems. i know that the a1-a15 is the correct fuel hose. just cant decide if i need to change it over right now. leaning toward using the oem stuff right now.
any thoughts? thanks

I replaced the tanks on my '79 tri-cabin last year and faced the same question. I decided to leave them alone under the "if it ain't broke, don't fix it" philosophy.

Agree with k9th, leave them if they are good.

Also, thanks for sharing about the antisophon valves, I shouls check mine, do you have a picture of what these antisiphon valves look like, seem like I remember several posts about them and location

This is the valve. It looks like a fitting but has a spring and clip in it. It will be at the top of the tank where the fuel line threads into.

Its basically an in-line check valve.

i think I need to look a bit closer, but if memory serves me correctly, I do not have them on my tanks, there is a shut of valve and the flare fitting on the fuel line....

i'll get back on this one

I would leave it. Copper is better than using newer hoses, especially with the impending doom of Ethanol at some point. Ethanol will not hurt the copper but does break down rubber hoses.

although this isnt my pic it is exactly what mine is. check valve is circled. i think i will proably use the oem copper for now. i ordered new valves today to replace my bad ones
heres the pic

http://www.marineengine.com/boat-forum/ ... 13&thumb=1

Thanks for the photo, ill look

Here is some info that may be helpful, taken from the link below.

Fuel Hose: When fuel hose is used it must be either USCG Type A1-15, USCG Type B1-15. Where you use it determines what type you use.

From the fuel inlet on the engine (usually the fuel pump) to the carburetor you must use Type A1-15.

Each fuel vent line or fill line must be USCG Type A1-15 and the line from the fuel tank to the engine inlet must be type A1-15;

UNLESS:

if no more than five ounces of fuel is discharged in 2 1/2 minutes when:

(A) The hose is severed at the point where maximum drainage of fuel would occur,

(B) The boat is in its static floating position, and

(C) The fuel system is filled to the capacity market on the tank label.

Then you may use Type B1-15.

As a practical matter, few boat builders want to have to stock two types of hose, so most buy only Type A1 and use it everywhere. This is fine. Just be sure that you put in your owner's manual that the hose from the fuel pump to the carburetor and the vent and fill hose must be TYPE A1-15.

So what is the difference between A1, and B1. A type hose has to pass the 2 ½ minute fire test, B does not. The theory is the A is under more pressure than B, and being on the engine is exposed to more danger of fire than B. Since B is between the pump and the tank, if a leak occurs, the pressure rapidly drops to zero and the pump just sucks air, stopping the engine. Fuel doesn't get sprayed all over the place. The fuel line between the fuel pump and the carburetor, or fuel rail, is under pressure and if a leak develops, fuel will be sprayed around the hot engine. So there is a greater risk of fire. This hose must be A1-15 which is fire resistant.
As Of 10/10/09: The US EPA has changed the permeability requirements for fuel hose. It must now allow not more than 15 grams/square meter of vapor to escape from the hose in 24 hours. This is 1/20 of what the USCG requirement was for type A2 and about 1/7 of the A1 hose. If is a very significant change. So check with your hose supplier. Hose should be labeled USCG A1 - 15, Or USCG B1 - 15

You do not have to use hose! You can use metallic lines. Some manufacturers do. For example, Mercury Marine inboard engines come with steel fuel line from the fuel pump to the carburetor. Metal lines do not allow vapor to escape through the fuel line walls.

Metallic fuel Lines: If you use metallic fuel lines, the ones that run from the fuel tank to the fuel inlet on the engine must be one of the following; seamless annealed copper, nickel-copper, or copper-nickel. From the fuel pump to the carburetor they can be any metal you want to use. Beware. You could set up a galvanic couple and the tube will be eaten away like powder. Choose carefully if you use metal fuel line from the pump to the carburetor. Do not use copper tubing. Pure copper is very subject to galvanic corrosion.

Anti-Siphon: The fuel line on a boat must run uphill, or else you have to have an anti-siphon device. An Anti-Siphon valve is that annoying little valve that most builders put at the tank outlet, that seems to get clogged at the most inconvenient times. So, if the top of the fuel tank is higher than the inlet on your fuel pump you have to put anti-siphon in the system. This is because the possibility exists that your entire fuel tank could siphon out into your carburetor, and fill up your manifold, and ruin your whole day! So, the solution is obvious. If you don't want this nasty little gadget in the fuel line, put the tank lower than the engine fuel inlet.

Clamps: If you use clamps, they must be used with hose designed for clamping. Sounds pretty obvious doesn't it. They must be placed beyond the bead, flare, or over the serrations of the mating spud, pipe, or hose fitting; and, not depend solely on the spring tension of the clamp for compressive force. Again this is pretty obvious stuff. In addition, the law doesn't require it but ABYC standards and good practice require that clamps be at least ½ inch wide, and each hose should be double clamped.


The above was taken from this link.
http://newboatbuilders.com/pages/fuel.html

Mike

Good info Mike, thanks.