bubbles in fuel line

[johnnyo34]

1972 Johnson 65hp. there's a very short plastic hose coming out of the middle carb to a T, then a plastic hose going to the top carb & one goes to the bottom carb.. When I flick the hose with my finger tip it looks like fine air bubbles up to the top carb, & fine bubbles below the T to the bottom carb.. is this normal just from the flick I gave it or is there air leaking someplace to cause this..

 

[F_R]

Re: bubbles in fuel line

1972 Johnson 65hp. there's a very short plastic hose coming out of the middle carb to a T, then a plastic hose going to the top carb & one goes to the bottom carb.. When I flick the hose with my finger tip it looks like fine air bubbles up to the top carb, & fine bubbles below the T to the bottom carb.. is this normal just from the flick I gave it or is there air leaking someplace to cause this..

Clear plastic fuel hoses should be outlawed. Why?? Because people see air bubbles in them and freak out. It is normal, and in fact try as you may, you will never get the bubbles out to stay. Relax.

 

[CharlieB]

Re: bubbles in fuel line

If motor performance seems to be reduced at or near full throttle and picks up if the choke is briefly touched to add fuel, then, often when troubleshooting a fuel problem we will TEMPORARILY install a clear hose between the fuel pump and carb(s) to watch for air bubbles which can indicate air leaking into the fuel system.

Once finished testing we ALWAYS remove the clear hose as it is NOT an approved MARINE RATED FUEL HOSE.

 

[johnnyo34]

Re: bubbles in fuel line

OK, thanks, I will replace with rubber hoses.. also there are little metal clamps on the hoses where they attach to the carb, but where they go onto the T there are no clamps of any kind... should there be clamps there? and I see on some fuel lines they have these plastic ties.. Is this an approved method of tightening fuel lines?? Wow I'm gonna learn something about owning a boat yet...lol.
John