Bad fuel pump?

[Bearskin9898]

I have a 1977 johnson 75hp

Everytime I go to start it the fuel primer is always rock hard. Disconnecting it from the motor and reconnecting it allows me to prime it a bit.. Should the motor be holding pressure for that long?
Also I noticed a bit if fuel would squirt out from where I connect my hose to the engine and around the fuel pump when priming. Should I replace the connector on the fuel hose or the one on the motor itself? Would it be worth just replacing the whole fuel pump as well?

 

[racerone]

There is something wrong here.-----The primer bulb should not be hard.----Replacing the pump won't fix the " hard bulb " either.----There might be a blockage in the fuel line or connecter..

 

[Bearskin9898]

There is something wrong here.-----The primer bulb should not be hard.----Replacing the pump won't fix the " hard bulb " either.----There might be a blockage in the fuel line or connecter..

I can squeeze the bulb if it's disconnected from the motor and I hold the pin down with a nail

 

[racerone]

???-----It should be easy to determine where the blockage is.----Remove one of the drainplugs on front of carburetor bowl.----Sqeeze the bulb.-----It should feel like you are moving fuel .---Fuel should pour out of the carburetor bowl.

 

[Bearskin9898]

Yeah I don't know anything about outboards or carbs. When this happens it seems like there is always a lot of pressure in the fuel tank.. But letting it out doesn't necessarily fix the priming issue . Boat starts up and runs fine on the lake. So I don't know if it's just normal for this motor or what..

 

[racerone]

What kind / brand of fuel tank ?

 

[Bearskin9898]

I'll have to look. When I went out there yesterday it was swollen up like a balloon..looked like it was about ready to pop.

 

[racerone]

Look for / get one of the older steel tanks that came with the Johnson / Evinrude motors in the 1960's

 

[Bearskin9898]

Look for / get one of the older steel tanks that came with the Johnson / Evinrude motors in the 1960's

Why a steel one?

 

[racerone]

Never mind.

 

[F_R]

Factory fuel tanks have a one-way vent valve (it's the Law---can't emit fuel vapors). That means it will allow air to enter the tank to replace fuel that was used, but pressure build-up within the tank from sitting out in the sun cannot escape. All this means that pressure in the tank is also pressure in the squeezer bulb, and is normal. Obviously, if there is already pressure in the bulb, it doesn't need any more priming, so don't fight it.

Ok, having said all that, there is also a pressure relief valve in the tank that allows air to escape if the pressure is so high as to be a danger. If your primer bulb is blowing up like a balloon the relief valve may be faulty, or the rubber bulb is all mooshy.

 

[GA_Boater]

His EPA tank is doing it's job.

Disconnect the fuel line from the tank or motor, maybe even both ends. Crack the cap to relieve the pressure before hooking up the hose.

I was writing this ^^^ as F_R was posting. I don't know and never looked what the blow-off pressure is supposed to be. It must be awfully high cuz my tank turns into a red peanut if I don't crack the cap.

 

[IDFISHER]

If your tank/boat is sitting out in the sun it will expand the vapors in your fuel tank and pressurize the tank/fuel line/primer bulb. With all that pressure in there, that's why fuel is squirting out when you disconnect the fuel line. If fuel is squirting out of the connector when you squeeze the bulb then you probably need to replace the connector. I bet if you leave your fuel tank vented while in storage your primer bulb wont be rock hard.