I bought a new fuel pump for my '51 Ford truck and it doesn't seem to be pumping. I have been told that the cam lobes under the push rods for the fuel pumps wear on flatties and once that happens you either have to replace the cam or go with an electric pump. Do you have to prime a new pump? If so, what's the best way? Also, I have an old electric pump that runs but doesn't pump. I took it apart and there doesn't seem to be any exessive wear. Do you have to prime electric pumps too, and if so, how?

 

Bob
Was the old pump working at all? How many miles on the motor, the cam ecentric should be good for a 100,000 miles, how did the pump push rod look?
I seek knowledge

 

I took the old pump out the other night and dismantled it. The main diaphram was dry rotted. I when down to NAPA this afternoon and got a new pump. I the pump push rod moves up and down about a 1/2". I took it out and matched it up to the one in my panel truck and they look identical, no noticeable wear.

I am now trying to reinstall the pump and I am having one hell of a time. The first time I installed it today I removed the tower, installed the pump on the tower and then installed it as one piece. I might not have gotten the cup on the pump arm to sit on the push rod correctly. This time I installed the tower then attempted to install the pump onto the tower. I cannot get the cup to sit on the rod. I am ready to douse the whole damn truck with gas and set it on fire!! I don't have a lot of patience when things don't go right. Is there a trick to install these pieces of crap of pumps?!!! I have had only experience with the flat six's, they are beautiful works of art compared to this pain in the *** eight!!!

 

Would it help to rotate the cam so the push rod would be in the lowest position?

 

Rotating the engine over a little like Christopher2 said could help you considerably!

Vernon

 

Also be sure the push rod is in right-side up. I think one end should be just slightly rounded or tapered to help it slip into the pump's cup. If it's upside down it's more square. It can be a you-know-what trying to install, assembling the tower to the pump is usually how I did it, and it would usually slide down easier. Using studs on the intake manifold instead of bolts helped to keep it straight and square sliding the tower down over them.

Scott

 

Bob,
Not sure how these flatties work, but a little grease on the push rod ends might might provide enough vacuum to hold it in place while you finish assembly. Works on an SBC.
Good Luck!

 

Bob

Any luck?

I was going to post some suggestions and the site was too busy. Saw the same thing on the Barn. Sometimes two people work better, one to bump the starter the other to work the pump.

 

I haven't had a chance to try any of the suggestions from any of the responses from here or the other boards. I worked until Saturday night on the beast and finally gave up before I torched the damn thing. Sunday I woke up sick as a dog and had to go to a graduation party. Today I had to work and other family obligations. I will try to do what was suggested tomorrow if I get a chance.

As for the physical condition of the push rod, it looks to be in good shape. I compared it with the one from the '48 panel and it was exactly the same. I had the panel running last year so I am assuming everything is OK with that one. It moves up and down about a 1/2" or more. I had a heck of a time getting the pump mounting onto the tower when the tower was bolted to the motor. I am going to try to mount the pump to the tower first and then bolt the whole assembly to the engine, like I did the first time around. I will take more notice to see if the cup seats on the end of the push rod this time. I am running a line from a gas can with new gas to assure I have a clean fuel source, I don't trust the fuel system in the truck because it has sat so long and I am pretty sure the tank is full of gunk and the lines are rusted. It just doesn't seem like the pump is pumping. If that's the case I will be paying a friendly revisit to my NAPA store. The service I got there Saturday had me fuming and if the pump is bad they aren't going to be happy to see me again.

I am working my way through the truck to make sure everything works before switching bodies with the '48 I just bought. When I bought the '51 last year the guy told me he couldn't get the thing to run, he thought he messed up the wiring, but when I fill the bowl of the carburator the engine fires right up and runs smooth and quiet. I had to file the points a little. It's one of the nicest running engines I have ever heard even with the hard plug wires and poor distributor cap and rotor. If I can get it to stay running the next thing is an engine flush to clean the cooling system, a tune up and an oil change. Then the tear down.

Once I get it running I'll let you guys know.

Thanks everyone for your help and if you can think of anything else please post it.

Thanks
Bob

 

The first thing I would verify is that the fuel line is unobstructed since it sounds like you may suspect that. Then, if you aren't sure about the cam lobe you could leave the pump off and put your thumb on the fuel pump push rod while someone bumps the starter to see if it goes up and down. The only other possibility I can think of is if the carb float valve is stuck shut. You could disconnect the fuel pipe at the carb and get a helper to crank it over while you stick the end in a jar.
BTW every electric (and mechanical) fuel pump I've had would eventually self prime but electric pumps work a lot better if they're mounted below the fuel level. Good luck and I'm sure you'll get the problem resolved soon Bob.

 

A buddy just went through the same thing with a NAPA pump for his '53 car. He installed it, nothing. I suggested he do some tests to isolate the problem. First thing I suggested was to operate by hand with a can of gas. The pump worked. Then, I had him hook it to the line from the tank. I wanted to make sure the line from the tank didn't have some pinhole in it. He pumped it by hand and got gas from the tank. Then he installed the pump, primed the carb, and she started. It's been running regularly for 2 weeks now.
Success could have been the result of priming the pump, priming the carb, or coincidence. It probably helped to have the line, pump, and carb full of gas, as taking the pump off will allow the gas to drain back to the tank.