New fuel line assembly 3/8 or 5/16 - does it matter?

[xzab]

I have a 1968 9.5 hp Johnson Evinrude (MQ14e) outboard and the fuel line assembly needs replacing. XXXXXXXXX shows the fuel line assembly using a 5/16 i.d. line -- but seems like it's a lot easier to find a 3/8 i.d. fuel line assembly than a 5/16 online. So my question is -- does it matter? Seems like some forums I see people saying stick with the 5/16 and others saying the 3/8 works fine too. Just want to make sure I'm getting the most out of my engine; if a 3/8 would improve speed by any chance I'd be up for that too.

Thanks in advance!

 

[interalian]

5/16" is plenty large for your 9.5. 3/8" would work too. No, it won't give you any more power.

 

[F_R]

You can use 3/8 anywhere 5/16 is specified, but you can't use 5/16 where 3/8 is called for (large V4 & V6 engines)

 

[xzab]

Awesome great replies, thank you!!

 

[xzab]

Sorry one more question: would getting the 3/8 size end up in any fuel inefficiency or anything? Wondering why others mentioned it may be "overkill". Thanks!

 

[racerone]

5/16" or 3/8" makes no difference on the way the motor will run !-----Has zero affect on fuel efficiency or power.----Ignore what " others " say on this matter !

 

[xzab]

Got it thank you!

 

[oldboat1]

but....should be able to order up 5/16 for less that a buck/foot. Think if meaning to replace the tank lines, it would be a good idea to get the bulb and hose assembly together, btw (use the current connectors).

Outside diameter may be a factor too, depending on where you are running it. I'm pretty sure that can vary in fuel hose for either inside diameter.

I don't want to get tossed overboard, but would get the 5/16 if there is a choice. Want good tight clamps either way, but probably especially for the larger ID 3/8 (fuel nipples for the fuel pump and carb are probably 5/16.)

 

[xzab]

ah, just saw this one -- the reason I ended up replacing everything in the first place is the connectors were leaking (and one actually snapped - they were pretty old). So I ended up getting a new complete 3/8 fuel line assembly (reinforced bulb) and new connectors. Gonna give it a shot and report back. Thanks for the info.

 

[sqzdog]

So, what'd you find out?

 

[GA_Boater]

So, what'd you find out?

The OP left no forwarding address - A year and a half ago!

Closed.