Fuel pump pass through?

[Jim G]

If I blow on the inlet side of the fuel pump on my 1949 Fargo, air should pass through? It does when the sediment bowl is off. I'm assuming a check valve is stuck shut, or there is a blockage someplace. but wanted to double check before I start chasing.

The suction line of the pump is in a jerry can and it doesn't seem to be sucking. The fuel pump is relatively new, but has sat quite a while.

[kencombs]

I think no, unless you create quite a bit of pressure.  The outlet check valve has to be unseated for air to blow through it.

[wallytoo]

how high are you trying to pump fuel up from the can?  as they sit in the truck, the fuel from the tank pretty much reaches the pump via gravity, and all the pump does is push fuel from there up to the carb.  asking it to elevate fuel from a low position might be too much.

[Jim G]

6 minutes ago, wallytoo said:

how high are you trying to pump fuel up from the can?  as they sit in the truck, the fuel from the tank pretty much reaches the pump via gravity, and all the pump does is push fuel from there up to the carb.  asking it to elevate fuel from a low position might be too much.

That is on the list of where to start chasing problems. the jerry can was sitting on the ground, toying with making a gas 'IV' but it got dark and my battery ran out of charge. This thing has always been hard priming/starting after sitting for a while. Dad and I used to have to tow start it in the spring if it didn't get ran at all in winter.

It has compression, it has spark, definitley hasn't got fuel, just chasing one problem at a time so I know where I am.

[1949 Wraith]

On vehicles that sit for a long time between being used I put in an electric fuel pump. I prime it with the pump before attempting to start. Run it for about 6 seconds then turn it off, sure saves the starter.

 

You can add fuel to the carb float bowl by attaching a small hose to the carb breather vent inside the throat, using a small funnel or syringe. If fuel pump is not working a remote fuel tank from a lawnmower above the carb should work if you want to run longer. 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[JBNeal]

additional information - carburetor priming made easy

[Merle Coggins]

I have also added an electric pump to prime my carburetor when it's been sitting for an extended period. I used to have it plumbed in series with the mechanical pump and found that sometimes it could push fuel through the mechanical pump and sometimes it wouldn't. I suspect that it had to do with the position of the diaphragm. Maybe it restricts flow through in certain positions? Sometimes I'd just have to give the engine a quick crank to get the fuel flowing again. The electric pump was also helpful when things got hot and the pump on the engine struggled to pump fuel. I could switch on the electric pump to help push fuel through the system. I have since re-plumbed my fuel lines and put the electric pump in parallel with the mechanical pump. This allows for easy priming, and it can still assist the system if needed. 

[Tooljunkie]

I gravity fed mine for most of the winter, moving it in and out of shop and storage. I went straight to the electric fuel pump and will not consider anything else. Ignition switch, oil pressure switch and a prime button. 

[ggdad1951]

FEF sits for a while during summer (coupla weeks generally) and starts right up with a little choke and 2 cycles on the starter.  After winter maybe 3 cycles. To me, that's just how these old boys work.

[wallytoo]

both the 237 that blew up and the 251 transplant start about the same.  overnight or longer, and it takes two tries to get it to run, with a little choke and the throttle knob pulled out a bit (not much).  two quick hits on the starter pedal, and it runs.  later in the same day, even after cooldown, it will start instantly with no choke or pedal application - literally just have to touch the starter pedal to engage the starter, and the engine is running.  less than a half-second of starter run-time.