41 fuel pump problem and frustration

[hombres ruin]

Hi guys I have a 41 ford flathead V8 with stock fuel
Pump . Today I went ahead and replaced the black fuel line that goes from the hard line to the pump . I also replaced the gasket from the fuel pump to the fuel stand and the fuel stand to manifold gasket as both were old and a little leaky. This is the first mechanical pump I have owned. I believe I put it back together correctly . The lever that comes from the pump with the cap on it goes over the fuel pump push rod in the fuel stand correct? I felt it push down and tighten all the bolts. The ride won't start I get no fuel at all. I have a electric pump to and that wasn't pumping fuel either . I have gas in the tank. Did I do something wrong or did my pump just crap out at that time?

[JSeery]

Is the electric pump running but not moving fuel? I would start cracking joints with the electric pump running and see where the fuel is getting to before it is blocked. Be careful it is flammable!!

[Vanspeed]

Was the black fuel line hard to get on? Could you have scrapped some of the inside that is now restricting the flow?

[hombres ruin]

Jseery.. I will check the connections under the car and see where the fuel stops and if there is a blockage.. Vanspeed.. The black fuel line was easy to go on and when I took it off again to inspect what was wrong I could blow through it and see light at the other end. So that's all clear

[deuce_roadster]

If the hard line going into the carb is too long past the compression ferrule, the end of the line can dead end and prevent fuel from flowing. Check both ends of the hard line and maybe put a rubber line from the carb end into a coffee can and see if fuel is getting that far. I had this happen at the fuel pump end.

[hombres ruin]

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So I disconnected the fuel line after the fuel pump and turned the pump on and gas is flowing. Then I took out the hard line after the pump to the firewall and blew it out and it was clean. Still no fuel coming out the hard line to the carb when reconnected .. I don't get it. I have a regulator set at 4psi in line. What the heck is going on. Fuel flows but when the hard line is connected.. Nothing

[JSeery]

Did you check the output side of the regulator?

[hombres ruin]

Yes I watched fuel pump freely from the pump. The last time I drove the car was a week ago. It was all fine then. The only thing changed is I removed the black fuel line and fuel pump to change gaskets etc that's all

[Kurt in NJ]

did you have the valves out of the mechanical pump---perhaps one is in the wrong way ---can you blowthgrough the inlet of the pump to the outlet

[hombres ruin]

Hi Kurt , no all I did was pull the pump away from the pump stand and replaced the gasket then I took the stand off and replaced the gasket to the manifold and stand . I replaced the fuel hose from the hard line to the pump . At no time did I disassemble the fuel pump. This whole thing defies logic

[JSeery]

Was there fuel out of the inlet to the fuel pump with the elec pump on? Maybe the mech fuel pump is not on the rod correctly?

[hombres ruin]

There is fuel coming out the electric pump no worries about that . If the mechanical pump is not on the rod correctly that still wouldn't explain why the fuel isn't coming out of the hard line to the pump ..

[SofaKing]

If you are certain the hardline from the pump is clear and fuel comes out of the pump when disconnected, is it possible the electric fuel pump is weak or obstructed and unable to push fuel the vertical distance to the mechanical pump? A test for this would be to attach a rubber line to the electric pump output and hold it up in the air several feet to see if fuel comes out. If it does you might also attach the regulator to the end of the hose and repeat. This way you can check the lift capacity of the electric pump with no load and again to see if it supplies enough for the regulator to modulate. You might also try bypassing the electric pump altogether and using only the mechanical. It seems extremely improbable but sounds like you have tried the more sensible alternatives.

[jimTN]

If you cannot blow thru the mech pump with the outlet line off then start from scratch and go thru it again.

[Steves46]

[QUOTE=hombres ruin;1272661]Hi guys I have a 41 ford flathead V8 with stock fuel
Pump . Today I went ahead and replaced the black fuel line that goes from the hard line to the pump .

From my experience, whenever a problem occurred on my 46, sometimes it was from the last change or repair I conducted. In order to further troubleshoot, did you try reinstalling the original black fuel hose you replaced? Steve

[JSeery]

Originally Posted by hombres ruin

There is fuel coming out the electric pump no worries about that . If the mechanical pump is not on the rod correctly that still wouldn't explain why the fuel isn't coming out of the hard line to the pump ..

OK, sorry, I wasn't following where all you had checked the flow. And of course you are correct, the mech pump should not be the issue (at least not so far! ). Think there were some good suggestions in post #13 about checking the elec pump capability. No idea why the timing would be connected to the hose change, but sounds like the electric pump is not working properly.

Here is a thought, the electric pump may have been weak before and the mechanical pump was capable of operating mostly on it's own with only sight help from the electric.