is there a check valve in fuel line?

hi,

I have a 1985 115hp merc. I am having problems getting the primer bulb to firm up. it is a new bulb and fittings. it is a 3/8 inside diamter fuel line. I have hooked up a different brand new attwood line and bulb and was unable to get any gas past the bronze fitting on the top of the tank. acutaully, i was unable to get gas anywhere past the top of the fuel pick up tube that sits in the gas tank. with the original bulb and fuel line its the same story. The tube in the tank has got a big diamter at least 3/8ID. should this line in the tank have a one way check valve on it? now it has nothing, not even a screen. the gas tank is a 12 gallon on-deck tank and it was full and still these problems. I noticed that the gas will come up only to the top of the intank fuel pick up line. Would a check valve help to pick up a prime?

Re: is there a check valve in fuel line?

Portable tanks do not usually have any kind of check valve. If they have a quick disconnect fitting, they will have an automatic fuel shut off as part of it. Does the tank have the brass Merc fitting? if so, is there a rod in the center of it? That would be the shut off valve. Your fuel line should push it in.

Those merc fittings can be hard to mate. They need to be pushed together tightly and then the female fitting turned a /14 turn. Remove the darn things and use a brass nipple and hose clamp.

Re: is there a check valve in fuel line?

The primer bulb has a check valve. That's why the arrow must point the right direction - toward the motor..

Re: is there a check valve in fuel line?

Hold the bulb upright rather than horizontal. They work better that way. If you have the hose disconnected from the engine youj cannot pump fuel because you are pumping against a closed line. Connect it to the engine and have a go at it. Is the vent open on the tank?