Fuel pump

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wheelsport

wheelsport

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When I bought my '65 Barracuda with 273, the fuel pump made a knocking noise and then failed because of dirt from the old fuel tank. The new pump also has the same knock but has worked fine. Is this normal? I don't like the way it makes the engine sound crappy.
 
i would pull the pump off, and look at the eccentric ( i think that is what the silly thing is called)
and inspect it for visable wear

then see if the pump can be moved up or down a little, to make sure the arm touched at all times
(also inspect the arm)
 
wheelsport said:
That would only be possible if NAPA, at two different stores, screwed up.
Click to expand...
Or, if over the 50 plus years that car has been around someone made some changes you didn't notice...unless you bought it new?
 
Could be that the concentric cam on the front of the timing chain is incorrect or loose. Or if the pump is not seating correctly on the block. The noise could be from the pump arm coming back in contact with the concentric for the pump cycle then leaving contact then recontacting then leaving contact...... ect. make sense? This would also create a shortened pump cycle since its not getting the complete ride. What PSI is the fuel pressure at ?
 
69FBCuda said:
Could be that the concentric cam on the front of the timing chain is incorrect or loose. Or if the pump is not seating correctly on the block. The noise could be from the pump arm coming back in contact with the concentric for the pump cycle then leaving contact then recontacting then leaving contact...... ect. make sense? This would also create a shortened pump cycle since its not getting the complete ride. What PSI is the fuel pressure at ?
Click to expand...
The pump fits well and there isn't any slop in the installation.
I had to install a fuel pressure regulator because the pressure too high.
 
Today I pulled the fuel pump to inspect the eccentric and found the pump arm completely dry with no oil at all. I then pulled the timing cover and found the eccentric with a small amount of wear but I don't think its enough to make a knocking sound. I think there is an oiling problem. Anyway the timing chain is worn and I'll replace it and look for a solution to no oil for the area.
 
The eccentric on the cam fits one way, if you pooch it, it will still be on but just wont be located correctly. Also the pump fits in the hole but wont seat properly until its bolted down so if it slides in and seats to the cover, something is wrong. The 'arm' has to go under the eccentric so the pump will be cocked down (lower tab not touching) and when you push the pump onto the cover, you'll feel spring resistance.
 
I know all that but my question is the oiling of the gears and eccentric. I pulled the timing case and I see that the oiling drips or splashes down out of the two holes on the face of the block. The eccentric appears to be OK. So how much oil should be in the timing gear area?
 
The knock could be the chain slapping. Is there some fresh scars inside the timing case? Oil should squirt from the 1 hollow bolt of the retainer plate and the slinging action should coat everything in oil. The pump does make a churning sound but only if its dry, once it pulls fuel it mellows out.
 
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