Flathead newb, but lots of engine building with musclecar era stuff. Posted a couple weeks ago about valve guides on an 8ba in a 1951 F1 & got good advice, so I'm back... The truck sat for a long time and the engine was very stiff. I pulled the intake/heads and all the valves/guides. A bunch were very sticky and at least 3 were frozen solid - thank god open, not closed so no bent valves or anything. Cleaned/polished/lubed everything & re-***embled. Engine turns over beautifully by hand. Hooked up a battery & hot wired the coil (not sure if the ign switch is good), plus gravity feeding the carb from a small tank - my regular procedure for getting an vehicle that has sat forever running. No start at first but once I installed new condenser & filed the points it barked right up! Awesome! But... I cannot get this thing to pump fuel. The owner (Bob) installed a new fuel pump prior to me working on it. I also tried the original ( I took it apart & the diaphragm looks fine). With the fuel pump off I cranked the starter - the pushrod is moving. I triple checked the pushrod has engaged the pump arm. Made sure the sediment bowl was properly seated with a good gasket. I don't understand WTF is going on....My last attempt was to prime the pump thru the inlet hose using a squeeze bottle full of gas. Ran a new hose from the inlet to a can of gas. Then I disconnected the line at the carb & ran a hose off it to a second can to check for flow. Fired up the engine ( bottle feeding it) - not a drop of fuel being pumped. I ran it for 30 seconds or so, I figure that should be long enough to start pumping fuel. If I bottle feed it or use the nurse tank it would run all day... Is there some weird flathead thing going on here?
If it sat for a long time I would think the check valves in the pump are stuck, or not seating. While the pump was off, you should hear the thing pump when you move the arm by hand, and it should make a little suction on your finger. Maybe having some gas in it will loosen things up...but maybe not
You could also test the check valves while its apart. Basically, they are one way valves, inlet side you should be able to blow thru, and with a piece of hose on it you should be able to **** on it and hold some vacuum for a bit.opposite for the output side. In a perfect world, they should hold some vacuum, but even if they leak a little it should run. Dont buy a new piece of junk, have your original rebuilt if you go that route.
Your pump rod may be a wrong length. Every aftermarket intake has a different height at the pump seat. Take the pump off and try it by hand. Most issues are related to a vacuum leak on a used pump. If you figure out the pump is good at the bench test you can then measure the needed length of the rod.
I'll tear apart the pump to test the check valves. Weird I would have the same issue with two pumps. Intake is original, not aftermarket. In fact everything is original. This truck is pretty amazing. It still had its original hoses & belts!
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