Merc 6 hp fuel delivery issue

[HickInTheSticks]

Having a new problem with my motor. Was running fine yesterday and day before with no issues...

Today I took it out and it would no longer siphon the fuel from the tank. I had to keep pumping the primer every 2 minutes or so in order to keep it running.

Fuel tank, line, and primer bulb are brand new (have only been out 3 times) and secured with metal clamps.

The connector to the motor (male fitting, I think) will leak fuel if i "Over-pump" the primer... meaning if I keep pumping it after the filter is full, the fuel will leak out the quick-disconnect fitting (also brand new) where it plugs into the motor. Doesn't leak fuel during any normal usage, only when I apply enough pressure to the primer will it start dripping out.

Tried running it with the fuel tank vent both open and closed, didn't make any difference, been running it open so I left it open.

Prior to taking it out the first time this year, I cleaned the carb and all fuel lines. No visible cracks or anything... didn't replace the fuel filter, but it worked fine yesterday and allows fuel through... just doesn't draw fuel into it.

Do not think my motor has a fuel pump? It's a 1996 Merc 6, 2 stroke.... feel like it runs on a siphon action. All the lines look good and the only way I know of to break a siphon is to add air to the line. Given my quick disconnect will leak fuel, I can only assume it'll draw air.

Is there a more permanent fitting than those quick disconnects? Mine is built directly into the motor, haven't actually looked but not too sure how easy it'd be to remove. I'd honestly just like a straight valve and a clamp. I'd rather put a metal disconnect in the middle of the fuel line rather than the plastic one on the motor.

Just looking to brainstorm to see if any other obvious solutions I'm overlooking pop up.

 

[earl60446]

Looks like your fuel pump is on the side of the carb.
That is where I would check first, see if it is pumping gas on the discharge side.
Diaphragm may have a hole in it.
Tim



https://www.boats.net/parts/search/Merc/Mercury/1996/1006201SC/CARB%286-8%29%289.9%20-USA-S-N-0G112449-BEL-S-N-9831799%20%26%20BELOW%29/parts.html

 

[Insanity]

Mine will pump up when unhooked from the boat. See if yours does. Then see if it holds it prime. Or is one of the connectors at fault.
If they are the screw on clamps and not factory crimped they will leak until tighten down twice sometimes. Mine also leaked at the tank where the connector threaded into the tank. Wasn't in far enough.

Mine doesn't leak at the motor no matter how hard you sqessh the ball. So I'm betting thats you problem if nothing above. If it leaking out that easy it suckling air in.

 

[HickInTheSticks]

Not leaking at the tank, mine leaks where my female quick disconnect fitting meets the male fitting on my outboard. It locks on properly and everything and is definitely the right size - the shop only had 2 sizes of Mercury and I bought both and one fits perfect.

Yet it will leak fuel when the primer bulb is compressed AND the fuel filter is full. It'll fill the filter without leaking as it should... once the filter is full the pressure causes it to leak out where the male/female connect together on the outboard.

It's just a crappy plastic piece and I'd much prefer a barb fitting to clamp the fuel line down to more permanently.

Been raining all day so I haven't really had the opportunity to mess with it.