Fuel line replacement

[walski]

I have a 1999 Honda BF90 that’s been a great motor. I replaced my fuel line from fuel tank to engine last summer as the bulb was getting pretty stiff. Wondering when I should replace internal fuel lines on the engine itself. No info in owners manual.
Thanks

[Bobby Winds]

When they start leaking.

[REW]

Walski,
Not a bad idea to check the lines.

But, after looking at a lot of boat, and checking under the hood so to speak, it seems that the largest majority of the boats are using a very alcohol resistant fuel line under the decks and seem to remain flexible with no issues for many many years.

Never hurts to check.

Good luck

[yarcraft91]

FWIW, my 1991 Johnson outboard still has all the original fuel lines under the cowl and they don't leak.

[walski]

Thanks for your input. If you have a 91 with no problems that’s got me thinking I’m worried about nothing. I’ll have to go through and see if anything feels crispy just for peace of mind. I have a 1965 Merc with original fuel lines, but that motors never seen any ethanol. I fish Canada every summer, and I know I get plenty of Ethanol in that gas. I don’t think my lines from 99 would be the alcohol resistant type???

[yarcraft91]

Originally Posted by walski

Thanks for your input. If you have a 91 with no problems that’s got me thinking I’m worried about nothing. I’ll have to go through and see if anything feels crispy just for peace of mind. I have a 1965 Merc with original fuel lines, but that motors never seen any ethanol. I fish Canada every summer, and I know I get plenty of Ethanol in that gas. I don’t think my lines from 99 would be the alcohol resistant type???

Hard to say without knowing what kind of lines you have. The OEM fuel pump in my '91 Johnson is a 2nd-generation pump designed to tolerate ethanol in gasoline and it has so far done that. Even my 1967 Plymouth still has some of the original rubber fuel lines and they are in good condition. That car has been run on E10 for ~30 years. OTOH, there are gray marine fuel lines with red lettering sold in the early 2000's that didn't last 10 years with ethanol exposure. I've never seen those gray lines installed under the cowl of a new outboard.

[walski]

Mine are gray with black lettering.

[REW]

Actually, outboard motors have been built since the 80's with alcohol resistant line.

Having said that - there are alcohol resistant lines of the 80s, and there are alcohol resistant lines of 2018.

Good luck

[TomP.]

The fuel lines will look great on the outside and not leak what needs to be checked is the inside of the lines for flaking. Had to change my 2000 Opti fuel lines the inside were just flaking away.

[walski]

That’s what I’m afraid of, what’s in the inside. I’ve heard of tiny black pieces of deteriorated fuel line screwing up carbs. I was told by a fellow fisherman that you can tell if you have the fuel lines with the ethanol resistant lining by the type of clamp used. The lining is slippery, and you need flat clamps to hold it. Regular fuel lines have wire compression clamps. I never heard that before, and haven’t been able to find anything on it. My lines have the small wire compression clamps holding the lines on. Anyone ever heard that before ?