Fuel tank to bilge - original copper or rubber USCG fuel line?

[ethan169]

1981 Glastron SSV-177 with a Mercruiser 165 L6.

I bought the boat used with a cracked block. Completely rebuilt the 165 with a good block. When I pulled the engine I pulled the gas tank as well.

The tank originally have a copper line running from the tank to the bilge (secured with plastic tie wraps with screw mounts). In the bilge it terminated with a barbed end with 3/8 rubber fuel line going to the fuel pump. I assume this is the original configuration however this is how I got the boat and I have no knowledge of its past life. I guess I want to know if I should replace the copper line with rubber (USCG with appropriate rating of course). I have the section of flooring that covers the tank removed and now would be the time. I talked to the guy at the parts desk at my local boat store and when I mentioned copper line he gave me a weird look like that was never the standard.

The copper line comes off of the tank with what looks like a JIC fitting or some sort of flared fitting. The other end as I said is barbed and goes to a rubber line which then goes to the fuel pump on the side of the block.

Any thoughts or suggestions?

Thank you,

 

[alldodge]

Don't know of anyone using copper, I think it was replaced previously. I would recommend using USCG type A1 rubber fuel line.

Also if you have the older type gas fill fuel hose, I would highly recommend replacing it. The ethanol will eat the older type hose up

 

[hemi rt]

Copper is not a good thing to use as a fuel line, copper and gas don't get along well. I would use a steel line that is coated against rust or use a steel line inside a rubber hose sealed and clamped at both ends to prevent water/moisture from getting in but definitely replace the copper

 

[CV16]

I have had two boats with the tank mounted in the bow. Both of them have copper lines running to the back just like the OP has. The one i still have is 42 years old. I'd think if gas didn't play well with it I would have had a problem by now. Show me a rubber hose that will last like that. I'd keep the copper line!

 

[third times the charm]

I concur with AllDodge....defiantly update the rubber lines with new rated rubber lines, or steel, or even stainless steel. Im going to refit mine with stainless with the new tank. Use rubber at the engine connections for eliminating leaks due to vibrations. Thats my two cents..

 

[third times the charm]

I have never seen copper used for fuel line....my experience. I have seen a few boats and vehicles over the years....no copper in them on the fuel side.

 

[ethan169]

Thanks for everyones opinions and recomendations. I agree that i dont see a problem with copper and fuel. However ill probably go with the rubber line for the whole run anyway. Its short and i need to get some of the uscg a1 stuff for the main feed anyway.

Thanks again!

 

[mickyryan]

I prefer rubber its what came stock on my boat to fuel pump , I have always wondered about copper/steel lines condensating if they were dry

 

[ethan169]

I picked up USCG A1 3/8 line for the full run but I looked at the copper again last night. I am 99% certain it is factory installed on this particular model/year. Everything else around it has dates on it of 1980 and the boat is an 1981. Plus I removed the floor over the fuel tank and the carpet and it looked original.

This being said the copper fuel line that I have is in excellent shape. A lot better shape then the rubber lines that I am replacing. So I have to think that copper is an acceptable choice of materials. Now how does it hold up in an accident or is it legal per USCG regs? I don't know...

BTW: here is a very useful link to the USCG Fuel system document from 2011 http://www.uscgboating.org/assets/1/AssetManager/ABYC.1002.01.pdf

 

[52FordF2]

I had an aluminum tank that had a copper line. The tank had pitting where the copper line laid against it.

I now have a plastic tank and will probable used rubber fuel line rated hose.

 

[ethan169]

Just and update for anyone that stumbles on this thread or for those that responded.

I purchased the USCG A1 3/8 line to run from the tank to the fuel pump however I noticed a few things when inspecting the original copper line. The fitting on the tank that looks like its an NPT type thread on the tank side and a single flared (accepts a flared) fitting on the goes-outta side. That fitting has a check ball in it. I assume this some sort of safety device that keeps stuff from flowing back into the tank? Or maybe protection during a fire? Either way I wanted to keep it since it was there originally. This meant I needed to keep a flared line. I could replace the copper with stainless but I didn't see a reason for that since the copper was in good shape and has lasted this long. In addition the copper line has a ground strap wrapped around it and brazed or soldered to it at the engine side. This strap has a large ring terminal that gets attached to the side of the engine block. I like this too since it grounds out the tank with the rest of the bouts ground system. Using a rubber line all the way back would mean that I would loose that ground and have to fashion a new grounding method for the tank. Which isn't a huge deal to do but I liked the way it was done from the factory.

In the bilge I use the USCG A1 line to connect to the fuel pump from the end of the copper line. Also used new stainless hose clamps on the rubber line. All of the supports holding the copper line are plastic type clamps and there is marine grade rubber used as a grommet between the plastic and the copper line, so no chaffing anywhere.

I put fuel in the tank and dropped the boat in the water for the first time in 15 years! She floats and runs! More on that in a different thread...

Ethan

 

[alldodge]

The spring loaded valve is called an anti-siphon valve. If keeps fuel from siphoning out of the tank into the bilge if there is a break in the fuel line.

Was on a 52 footer yesterday and there was copper lines all over it for fuel lines. This was diesel and an older model, but still the same

 

[72fj40]

Our 77 Chris Craft Lancer has its original copper fuel line. I thought one reason for the use use of copper was because it doesn't spark. If you read the Coast Guard regs it says to use copper or ni-cop.