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Teach me about fuel hoses

RStyleRStyle Senior MemberBoynton BeachPosts: 1,715 Captain
Was changing Racor with a friend on his boat and noticed his fuel hoses were dry, super stiff and with small surface cracks.
1)) how often should they be replaced. Should it be a routine every couple of
     years maintenance thing?
2) Is it true that grey hoses collapse or disintegrate inside?
3) are there options other than grey hoses.
4) change the primer bulb at the same time? It also seemed to have small
    surface cracks although easy to squeeze

Replies

  • chaser48chaser48 Senior Member San Mateo Fla.Posts: 345 Deckhand
    Grey hoses do disintegrate ask me how I know,replaced mine with black fuel hose
  • CaptjamesCaptjames Pompano BeachPosts: 231 Deckhand
    Yes, You want black outer core and black inside core fuel hoses.  Depends on how the boat is stored......in a garage, baking in the sun on a lift......I'd say 10 years, but start inspecting carefully at the 6 year mark.  Yes change primer bulb at the same time. 
  • RStyleRStyle Senior Member Boynton BeachPosts: 1,715 Captain
    chaser48 said:
    Grey hoses do disintegrate ask me how I know,replaced mine with black fuel hose
    Just curious. When you say it desintegrates. What happens? It breaks and spill fuel everywhere??
  • lemaymiamilemaymiami Senior Member Posts: 4,773 Captain
    Avoid any fuel hoses that aren’t clearly marked on the outside with a Coast Guard rating.  That means do not buy any cheap Walmart or other big box store ready made fuel lines.  You’ll find what you need by the foot at any good marine hardware store.  I’ll explain why in my next post…
    Tight Lines
    Bob LeMay
    (954) 435-5666
  • lemaymiamilemaymiami Senior Member Posts: 4,773 Captain
    Now for a quicky fuel line tutorial... from a guy who had to learn all of it hard way "aren't boats fun".

    Different sized motors need different sized fuel lines... The fuel line for a 200hp motor is bigger than the fuel line for a 20hp motor... and if in doubt your owner's manual for the motor you have will tell you specifically what sized fuel line you need... and every motor manufacturer will also have their own brands of accessories that if you stick with should provide what's needed... The trouble comes when you try to save a buck (or not go to your dealer...).   By the way fuel lines get old and get stiff and eventually will begin to crack and have leaks - so check your lines every year and when they're no longer flexible start thinking about replacing them... before trouble starts if you can...

    Years ago, all we had was gasoline, then came additives and finally starting more than 40 years ago gasoline mixed with alcohol... Pretty much the cheapest fuel around and what most of today's cars were designed for.  The problem comes from the fact that alcohol is not only a solvent - but it will attack anything made of rubber (hoses, gaskets, all the stuff that needs to be working properly or your motor won't run right - and eventually won't run at all..). Manufacturers responded by changing out most of their gaskets (but not all) and so did the folks who make fuel lines, fuel filters, etc.
    That's where the Coast Guard stepped in and began rating fuel lines with clear markings on the outside every 18 or 24".  It will say "USCG RATED ACOL TYPE...." etc.  - if that fuel line can handle fuel with alcohol in it.  Are there still fuel lines that can't handle alcohol - oh yeah.... Are there gas stations that might not tell you that their gas has alcohol in it? -oh yeah... So that's why you avoid unmarked fuel lines - no matter how much cheaper they are... 

    It gets worse.. if you're running any alcohol in fuel lines not meant for it.. the line itself will be begin to crumble - but not from the outside - it will start on the inside where you can't see it and those small bits of rubber will end up in your motor where they'll damage it and eventually shut you down... Something to remember... no motor warranty (even with a brand new motor... ) will cover you if you put bad fuel into it... 

    More stuff to know about fuel with alcohol in it but I won't cover that here - except to point out that all of my motors for years now have run alcohol laced gas without the slightest problem - but I've been set up for it - and I've run Evinrude E-Tecs since 2005 (that will change now that they've quit making them and I'll have learn about fuel in four stroke motors).  Many choose to run straight gas (no alcohol) called Rec 90 mostly... The problem for someone that's a high end user though is most gas stations don't carry Rec 90... Straight gas has more power in your motor than gas with alcohol so there's that incentive as well as getting away from the troubles that alcohol can cause... so that's your choice if you're running a boat...
    Tight Lines
    Bob LeMay
    (954) 435-5666
  • gogittumgogittum Nature CoastPosts: 3,669 Captain
    I went thru this just recently.  Some fuel hoses are made with a plastic liner inside the main hose.  On a motor I bought recently, the hose was soft at the motor fitting and "didn't look right," so I tried to pull the connector off to check it.  When the hose came off, it left a white plastic liner still attached to connector.....and the liner was coming apart.  The hose itself was breaking up around the liner.

    When I went into Apopka Marine for new hose, I mentioned it to the very knowledgeable guy at the counter, since I'd never seen or heard of such a thing.

    His eyes got wide and he said, "omigawd, get rid of that stuff - it'll clog up your motor."

    When I bought the 2nd, larger boat, I went thru the same thing with a different colored hose, (1st hose was grey, 2nd one black) so don't depend on a black hose automatically being a cure-all.

    As an aside, I had a bit of a struggle with hose and fitting sizes that caused some frustration.  Take a fitting in with you when buying hose.  Just because the box says 5/16" hose doesn't necessarily mean it'll fit a 5/16" fitting.  Sounds silly, but I'm very serious......I went thru that, too.

    I find it somewhat hard to believe that some people would manufacture such garbage and that others would actually sell it......but they do.  The education continues.
  • CaptjamesCaptjames Pompano BeachPosts: 231 Deckhand
    RStyle said:
    chaser48 said:
    Grey hoses do disintegrate ask me how I know,replaced mine with black fuel hose
    Just curious. When you say it desintegrates. What happens? It breaks and spill fuel everywhere??
    The inner core disintegrates into small pieces and clogs your fuel filters, high pressure fuel pump and is a very costly fix.
  • chaser48chaser48 Senior Member San Mateo Fla.Posts: 345 Deckhand
    What Captjames said is what happened to my filter setup
  • BillgranBillgran Senior Member Posts: 350 Deckhand

    *****************************************


    "There is never just one thing wrong with a boat"
    --- Travis McGee


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  • MissedMissed O-townPosts: 659 Officer
    I just rigged a new fuel tank in my boat this year and bought some pricey fuel line.  It has a 2 part outer shell and a clear inner liner.  Go figure.  Then again, so did my "old one" that is 4 years old, as did the fuel line I got from the dealer with the brand new motor last year. 

    Since all 3 brands have it, gonna guess that most alcohol rated fuel lines have a clear plastic liner.  I really thought I was getting a solid 1 piece, plastic fuel line made outta some special PVC hose.  Was surprised that it weren't so cause you can't see the liner in the fuel lines.

    Ran the new fuel line thru a piece of 1-inch PVC from front to back and figured that would help protect it from damage.  Put an inline filter on there for giggles.  If the tank got any crud in it, be nice to catch it before the motor's little filter does.

    Also started running Startron in the boat gas.
  • CaptjamesCaptjames Pompano BeachPosts: 231 Deckhand
    Shields that West Marine sells, doesn't have the clear plastic liner. 
  • lemaymiamilemaymiami Senior Member Posts: 4,773 Captain
    Did that "pricey fuel line" have a Coast Guard rating on it clearly visible up and down the line?  If not.... you've been had... The fuel line on my skiff is marked as above, is all black, with no "clear liner" inside... 

    I wouldn't trust anything else in today's world where you're very likely to find alcohol in any fuel - not matter what they claim.... An "in line filter for giggles"  is actually a necessity on any boat - the canister type (or the ones with a clear bowl where you can see what's accumulating) isn't meant for debris as much as it is meant for a water trap - to prevent any water in your fuel tank from getting to your motor.

    I figure almost any fuel tank will have some water in it... Look at you car at first light and note the dew on it... The inside of your fuel tank (the part above where the fuel is...) isn't any different... The big trouble for boat tanks is that the water sinks down under the fuel (water and gas don't mix - unless you're running alcohol in your fuel...) and just stays there forever... On a nice smooth day on the water you'll never have the slightest water problem (unless you've gotten a lot of it in your tank...) but on a rough day that water will manage to make it into your fuel line a bit at a time and that "water trap" (your fuel filter) should catch most of it, hopefully... How to prevent or minimize water in any fuel tank ?  Pretty simple, just keep your tank topped off (and I won't put my rig in the garage at the of a day's work without topping it off...).  That minimizes interior metal surfaces where moisture in the air can condense over night and begin that cycle of water contamination of your fuel... Leave that tank half full (or less) and let it sit for weeks or months - then expect water troubles.... 

    Hope this helps, "aren't boats fun?"
    Tight Lines
    Bob LeMay
    (954) 435-5666
  • MissedMissed O-townPosts: 659 Officer
    Did that "pricey fuel line" have a Coast Guard rating on it clearly visible up and down the line?  If not.... you've been had... The fuel line on my skiff is marked as above, is all black, with no "clear liner" inside... 

    I wouldn't trust anything else in today's world where you're very likely to find alcohol in any fuel - not matter what they claim.... An "in line filter for giggles"  is actually a necessity on any boat - the canister type (or the ones with a clear bowl where you can see what's accumulating) isn't meant for debris as much as it is meant for a water trap - to prevent any water in your fuel tank from getting to your motor.

    I figure almost any fuel tank will have some water in it... Look at you car at first light and note the dew on it... The inside of your fuel tank (the part above where the fuel is...) isn't any different... The big trouble for boat tanks is that the water sinks down under the fuel (water and gas don't mix - unless you're running alcohol in your fuel...) and just stays there forever... On a nice smooth day on the water you'll never have the slightest water problem (unless you've gotten a lot of it in your tank...) but on a rough day that water will manage to make it into your fuel line a bit at a time and that "water trap" (your fuel filter) should catch most of it, hopefully... How to prevent or minimize water in any fuel tank ?  Pretty simple, just keep your tank topped off (and I won't put my rig in the garage at the of a day's work without topping it off...).  That minimizes interior metal surfaces where moisture in the air can condense over night and begin that cycle of water contamination of your fuel... Leave that tank half full (or less) and let it sit for weeks or months - then expect water troubles.... 

    Hope this helps, "aren't boats fun?"
    There's different ways to skin cats and diff opinions on just about everything.  At least up til we got You Tube and the first guy to post a video is the "right one"  :o

    Fuel line is marked - so are the other 2 brands.  I never liked the black fuel lines - back in the day, we used to run clear vinyl tubing to be able to see the gas flow between the ball and the motor.

    I put a particulate filter on there, not the water catcher.  Using a 13-gallon can and it gets cycled-thru pretty regularly.  I bet your tank and motor are bigger than mine, and that you run them a lot more while guiding folks.  

    The condensation concern is minimal but does happen.  And ethanol gas is known for it.  Topping off and using fuel stabilizers helps.  

    As with everything - it falls into an "if you take care of it - it will take care of you" concept.
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