Fuel lines

richlee

Cadet
Joined
Sep 20, 2016
Messages
6
Fuel line question

My old outboard fuel tank (metal) has finally had its day along with the fuel line and bulb. Neighbor gave me a better tank but it has a 3/8 line rather than the 1/4 on my old tank. My motor is a Honda 8 horse. Does the size of fuel line make a difference? Thanks for your thoughts.
 

alldodge

Moderator
Staff member
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Mar 8, 2009
Messages
40,751
This is one of those questions which should be in the outboard section, because they know more about the fuel pump in the small motor. Until one of those guys come along my thought is, your motor should have no issue running so long as the fuel pump can draw from that size line.

A 1/4 line has very little volume so drawing fuel up that small line would be easy. Change to a 3/8 line and the pump has to work a tad harder. The difference between a 1/4 to 3/8 isn't much but if it does require a tad more suction. Is it enough of a change, maybe not but I'm unsure
 

richlee

Cadet
Joined
Sep 20, 2016
Messages
6
My old fuel tank and fuel line has given up the ghost. Neighbour gave me an extra that he has. My question: my old tank had a 1/4 inch line and the one he gave me has a 3/8 line, is this a problem on my 8 horse Honda? Thanks for your thoughts
 

pvanv

Admiral
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Apr 20, 2008
Messages
6,509
As long as you have the correct connectors, you will be fine.
 

ahicks

Captain
Joined
Sep 16, 2013
Messages
3,957
I would take your neighbors offer of the tank in a heartbeat - as long as it's clean internally and hasn't been sitting around for many years unused. If the neighbors line is in good shape, I'd say go for it as well. If there's any hint it's old, or it's stiff, you might just as well take the time to do it right and replace it. Most taks are set up with replaceable fittings. It might be something you can swap from your old tank. You could also view it as a good time to replace those fittings as well.
 

km1125

Chief Petty Officer
Joined
Aug 10, 2016
Messages
496
The issue is going to be if that 3/8 line will clamp down on the hose barbs or not. If you already have the connectors on it, then it's OK, but if you have to put that hose on where the 1/4" hose was, it likely won't seal very well. I bought an older outboard where someone did something similar and it sucked air in easily. If I used the hose bulb to pressurize it, I got a gas leak. The motor would run OK at lower speeds but basically run out of gas at higher speeds/loads where it needed to pull more from the tank. I replaced it with smaller hose and it works great now.
 
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