Fuel Lines/pipes

[dansar]

Hi

The yacht we've just bought (June) is being prepared for the voyage down from Scotland to the Humber--it's a little nearer home so during the winter months we can travel daily instead of the 5 hour car journey + ferry.

One potential problem that I found last week was the fuel line from the water trap to the lift pump, then from the lift pump to the filters, then from the filters to the main pump, were all plastic and there was, due to vibration over the years evidence of damage to all the pipes where they are fastened to the lift pump/filters etc. Of course, apart from having the smell of diesel in the engine compartment, there could have been the problem of air entering the system. /forums/images/graemlins/shocked.gif

Obviously these pipes need replacing and in the past I have used braided fuel lines, which allow for vibration--a little more expensive but I think worth it.

My question is "What type of pipes do you have on your engine(s) and have you checked them recently?

Your comments please.

Thanks

David

 

[gorb]

Mine are all copper (about 8mm diameter, I think) and looking good after 20 odd years. Have just replaced a water trap/filter unit so have had a recent look at them. There is a flexible braided line from (fixed) tank to (moving) engine.

Gorb

 

[beneteau_305_553]

The pipes on mine are zinc plated steel with flexible rubber hoses at ends that fix to the filters etc.

I am concerned that the steel pipes are corroded and need replacing. Am thinking of replacing with fuel grade rubber hose all through.

 

[Ships_Cat]

What type of pipes do you have on your engine(s) and have you checked them recently?

Our own boat is fitted with simple plain fuel use approved heavy wall rubber hose. However, our fuel tank is in the keel, the fuel line is only about a meter and a bit long, we have no lift pump between the tank and the engine itself, and is all in the bilge. So there is no significant source of fuel to feed a fire if the hose ever burnt through (apart from that in the hose and the primary filter). Also, I would suggest that in the circumstance that there is a fire in the bilge big enough to do that then one has major problems in any event (the bilge is the last place to get burnt out). The leak off fuel return to the tank is the same.

The primary filter is located next to the seacock for the galley drain and the connection to the tank is next to the seawater inlet seacock (for toilet flushing, freezer, etc) so the fuel line connections are inspected by default every time those seacocks are used (at least every time we leave or board the boat).

Whatever you do make sure there are no special requirements for the home waters you cruise in - some places, especially inland, have "blind" requirements which take no account of individual circumstances eg you may have to have metal lines regardless of the actual need for ones own arrangement.

John

 

[twisterkai]

As I recall, the approved method is copper piping for as much of the run as is practical, with flexible connections kept as short as possible. Fuel line from autofactors, whilst being usable, is generally not acceptable. I think the correct grade is A1, and swindleries charge about £6.00 per metre, but it's definately worth shopping around. The A1 grade fuel line is black twin wall rubber with a fibre reinforcement bonded between the inner and outer walls. The clear reinforced 'fuel grade' pipe is frowned on, precisely because of the hardening process that occurs over time because of the diesel running through it.

 

[savageseadog]

Fuel lines should be non flammable, flexible lengths should be braided stainless full spec I'm not sre of but is available from plumbers merchants for oil fired boilers. The rigid sections should be in Cunifer or Kunifer which is available from commercial brake equipment suppliers.Great care should be taken to prevent vibration fatigue by securing at close intervals.

 

[billcowan]

yep, replaced all mine with black twin wall rubber. cable ties to keep it away from exhaust manifold!

Oh, and one tip. tighten jubilee clips with a socket or spanner, tighten them to one turn off busting. AND after a bit of motoring, check em again for tightness - the rubber squiges a bit.

I'm told inland waterway jobsworth types like to see pipe with the writing on showing the spec.

 

[snowleopard]

As a further precaution against chafe, put a bit of split hose over the pipe anywhere it crosses a hard edge. Hold in place with cable ties.