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Have a 48 Packard Deluxe with 288 engine. When running get a constant tap like a valve needs adjusting. That said went in and adjusted the valves to spec but still get that annoying tapping sound. Used a stethoscope and not hearing any particular noise valve but when put by the fuel pump it’s tapping is in sink with engine tap. So questions are… am I heading in the right direction and when mechanical pumps start to wear do they start tapping loudly?

There is a mechanical interface with the cam shaft. The 1st large lobe on the cam runs the arm that actuates the lever that runs the diaphragm. What may of happened is that there may have been enough wear on the arm or cam lobe that there is now a spot in the cycle where the cam and arm no longer touch, then a tap sound occurs when the lobe comes back in contact with the arm of the pump.
On mine my rebuilder built up the arm's cam follower pad with weld and refaced it, that may be required on yours. Just about all cam shafts have wear on the fuel pump lobe so I suspect that any wear that there will be on that lobe is still okay, which is proven by the fact your pump works so there is sufficient 'throw' to pump the fuel. Like it has been pointed out on other threads, the pump delivers far more fuel than necessary anyway.
Bob J.

It could be worn linkage too. Easy enough to check.

How do you check the linkage?

Remove the pump and watch for play between the arm and the diaphragm(s).

Got it! Thanks! Appreciate the help.

All of the above, plus a weak spring in the pump or loose attaching hardware. It needs to be investigated to avoid fuel pump failure, possibly with small parts falling into crankcase. I've had fuel pumps make hooting sounds, but what you describe sounds like a developing mechanical issue.

Attached is a video of what I am hearing after the valve adjustments…

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And under 10MB.

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