Replacing Copper Fuel Line, and Other Issues

[kazenza]

I have a newly purchased 1980 CT Trawler with fuel issues. I have a weepy starboard tank (200 gal) that I intend to dry out and remove. the other two tanks (especially aft) appear sound so I will clean those out and recoat the outside and replace senders etc. The copper fuel line appears all original, is kinked in a couple of places, and is quite corroded on the outside. My question is whether to replace the copper with copper or to replace it with an appropriate synthetic fuel line. Secondly, if I replace it with copper, is this something beyond the skills of A DIY. I have run copper line on a diesel tractor but am by no means accomplished and this is a lot of line with a lot of connections.

[Pete7]

I would go with a flexible fuel line. There are standards particularly on commercial boats and in the UK it's ISO 7840 if memory serves me right. That said I used quicksilver fuel lines on a previous diesel commercial vessel and the surveyor passed it. Properly supported and protected from heat and moving parts it will be much easier to fit.

We will replace our copper lines at some point because they have too many joins in and then change to a flexible hose in the engine bay anyway. I would prefer one continuous line with no breaks to reduce the chances of leaks or air getting in.

Pete

[David M]

I did all the copper fuel lines for my boat when it was a Subchater-T inspected vessel. I wish so much I could have ran flexible hose as bending and flaring copper fuel line is a PITA.

If you do go with flexible fuel line get it professionally crimped at both ends with JIC compression fittings which makes for a much more secure connections....this is the same way hydraulic hoses are done and done by the same people that do hydraulic hoses. I think it is worth the extra effort to minimize the chance of fuel leaks by doing it this way. While you are at it, make up a long temporary fuel line in case you do have a hose that does go bad.

[GordMay]

Greetings and welcome aboard the CF, kazenza.

What my predecessors have said go flex hose.

[Tynesider]

Originally Posted by kazenza

My question is whether to replace the copper with copper or to replace it with an appropriate synthetic fuel line. Secondly, if I replace it with copper, is this something beyond the skills of A DIY. I have run copper line on a diesel tractor but am by no means accomplished and this is a lot of line with a lot of connections.

Hi Kazenza
You do not say what size your existing copper fuel pipe is, 2 years ago I had fuel problems for ages on old copper pipes but in the UK we call it 'Microbore' copper tubing which is less than 6mm dia at best and very difficult to clean out but great for getting blockages in it.

I re piped both tanks and all pipework myself and went for the approved certified rubber diesel piping, one big advantage apart from being much easier to fit is the bore for the delivery fuel is a larger at 3/8" dia and the return 1/4" dia, also 'if' a problem it takes minutes to disconnect.

You can easlily fit valves and fittings using just using hose tails and to date I have not has any trouble.

Hope this might help
Mike

[James S]

When I re-powered I replaced the copper with flex.
As David says the crimped connectors are nice, but IMO not necessary, as the pressures are very low.

[Alaska JD]

Flex is so much easier to deal with than copper. Using flair fittings with copper is pretty easy for a DYI but flex is a much better deal

[Artif]

Personally I would replace the copper with copper with a short length of flexi to connect to the engine.
Flexi hose has a limited lifespan and unless you use fire rated hose you have the obvious potential for feeding any fire with fuel.
You must ensure that the copper is routed and fixed well to avoid damage and vibration (goes without saying for either type of fuel line).
The boat safety scheme here in the U.K. has the same recommendations Boat Safety Scheme - flexible hoses

[motion30]

nothing wrong with copper and with a little effort can be bent neatly with the proper bender Save a few dollars as well most boats have rubber

[kazenza]

Thanks everyone for the great feedback. I used to restore tractors as a hobby and I have to say that everyone here was much more positive and helpful than I am used on the old tractor forums. I am thinking that I will go flex at this point, but I have to polish my good tanks and transfer fuel before that. the old Lehman 120's on this boat have about 2000 hrs on them and fire right up so hopefully I'll be in good shape once I get my fuel system sorted.