Extending fuel line on outboard problems

[Slayer33]

Hi all,

I recently extended my fuel line for my merc 20hp 4-stroke outboard. I am using the stock quicksilver tank that comes with the fuel demand valve included.

I needed to add 4ft to my fuel line cause I wanted to relocate my fuel tank to the front of my 12' SIB to balance out the weight.

I used a 3/8" non-fuel injected fuel line between the primer bulb and the fuel demand valve. This hose was 8ft long.. the hose I removed was about 4ft..

After doing this I wasn't able to prime the fuel anymore.. no leaks etc..

I can hear the fuel demand valve making a thumping noise each time I pump the bulb...

Is my issue with priming now because of the added 2ft of fuel line? or is it because I didn't use a fuel injected fuel hose which has stiffer walls? The fuel line that came off was fairly stiff.. but still could that be the issue? The tank is no lower or higher in height than the motor.. within 1ft..

Should I relocate the bulb closer to the tank? or maybe remove the fuel demand valve all together?

I read that the valve has a manual bypass on it.. but I have no idea how to switch it...

Can anyone help?

[paintman]

I presume your bulb only allows fuel to pass one way and that you've refitted the bulb the right way round?
The pick-up tube in the tank hasn't fallen off?
The pick-up tube is in the fuel?

After checking the above disconnect the tank end of the hose from its connector so you have just an open tube & put it in the fuel. Squeeze the bulb & see if it draws fuel.

[Slayer33]

Originally Posted by paintman

I presume your bulb only allows fuel to pass one way and that you've refitted the bulb the right way round?
The pick-up tube in the tank hasn't fallen off?
The pick-up tube is in the fuel?

After checking the above disconnect the tank end of the hose from its connector so you have just an open tube & put it in the fuel. Squeeze the bulb & see if it draws fuel.

Yes its a one way bulb.. it is the correct way..

I'll check the pick-up tube, but I don't think that is it either, the tank is about 2/3 full so I can't see that being an issue as well...

I could get the fuel to come about 3/4 of the way through the new fuel line but it wouldn't go any further...

I feel it has something to do with the fuel demand valve.. or perhaps that the fuel line I got doesn't have very stiff walls vs the stock tube which was quite rigid..

[uncle al]

disconnect the the fuel line on the engine end,remove the fuel connecter out of the pipe, put the hose in the fuel tank, you now have a circuit prime the fuel bulb, it may be just an air lock. I have had a few swear word priming fuel through sometimes when I've rigged boats, with OBMs.