When To Replace Raw Water Hoses

[h2oski]

Hi,

I'm updating the fuel system in my 1999 AN, that includes the fuel fill hose. Yesterday I removed the original fuel fill hose and I noticed a year marking, 1999. I looked around the engine and the raw water hoses have a year marking too.

Sorta like tires on your vehicle, they have a manufacturing date...

I did replace the fuel fill hose (2021), it touches fuel, it looked fine to me though, but what about the raw water hoses. Mine look fine, they feel a little stiff but they have a wire twisting through them.

Do we need to replace the raw water hoses, if so, how often, 5, 10, 20 years or when?

TIA
Scott

[NautiqueJeff]

I don't replace them unless they are leaking. I have seen a few that did leak, and I replaced those. It is a good idea to replace the fuel lines and hoses every so often though, especially older ones that weren't meant for ethanol.

[h2oski]

Thanks NautiqueJeff. Regarding the rubber fuel lines and hoses, I've learned probably more than I care to know about them. In my case, I gradually started noticing raw fuel fumes every time I removed the cover. No leaks any where, boat ran fine, no ideas. Then I learned what permeation is and how in the early 2000's the EPA changed the rules about rubber fuel lines and hoses and the allowable release (permeation) of fuel molecules into the atmosphere.

Correct Craft used gasoline and alcohol rated fuel lines in my boat, but as the fuel hoses age, they break down and fuel fumes permeate or escape through the walls of the fuel hose. Today, the USCG requires A1-15 low permeation fuel hoses to be EPA/CARB compliant. I also learned that fuel hoses should be replaced every 5 to 8 years. I'm not sure if that's true, marketing, or a guess :-)

Long story short, once I replaced the supply and return fuel lines (and all the screw mounted zip ties securing it), no more fuel fumes, odor, vapor, and smells like a boat again.

-Scott

[shag]

Ethanol was the worst thing for older boats and caused many fuel related problems in not only marine engines/fuel systems, but small engines like mowers and weed eaters as well. Good case of the government not looking at all the ramifications before enacting laws.
As far as your water hoses, if they begin to start showing small cracks into outer covering or look brittle, I would replace. The ends can sometimes mushroom a little and if there was ever a time that clamps were over tightened there's a slim chance it could have damaged the end of the hose a little bit. Depending on model, sometimes hoses aren't too expensive and maybe if they aren't, and you're servicing the boat anyway - it may be cheap insurance and/or peace of mind to replace them... Just my .02

[h2oski]

Thanks shag I seem to deal with ethanol issues with my small engines every spring, even with fuel treatments or draining the fuel out.

I checked our vendors here and I'm going to replace the water hoses. After closer inspection, the ends on the manifolds and thermostat have a few cracks and slightly mushroomed. Like you say, cheap insurance/peace of mind.

-Scott

[shag]

Thanks shag I seem to deal with ethanol issues with my small engines every spring, even with fuel treatments or draining the fuel out.

I checked our vendors here and I'm going to replace the water hoses. After closer inspection, the ends on the manifolds and thermostat have a few cracks and slightly mushroomed. Like you say, cheap insurance/peace of mind.

-Scott

Ah good to catch them. And I only use ethanol free in all my small engines and boat (not sure if its available around you) and have not ever had a fuel issue since. Boat or lawn equipment can sit for months without use and they start right up and run great. I have also looked inside my FCC canister after several years using ethanol free (even with boat sitting for months at a time (sadly) and it's always clean as a whistle.

[h2oski]

We have a QT station near that has ethanol free fuel that I've been using, it's 90 octane. It's a bit more expensive, but over time I think it'll pay to use it.

-Scott