The fuel pump cam I believe is actually part of the intermediate shaft on these, it cannot come loose, or distributor would not turn.
Fuel pump if good will prime carb unless filter or something else stopping up fuel line. Ethanol plays havoc with fuel line now unless you have ethanol tolerant line. The Gates hose mentioned. You can blow back through fuel tank with compressed air and listen for it bubbling to know if pickup filter is clogged. Have cap off when you do it. Ethanol also very bad about sticking float shut from the residual sugar in it after car or bike sits for more than a week. I've had to take compressed air to fuel inlets before to just pop needle free of seat. Either that or take carb apart to merely touch needle to have it come loose. A pain in the -ss and plenty of fun on inline four bikes.
Rather than prime engine through butterflies I simply fill carb up through the vent area on 5200s. Pump throttle 2-3 times till pumpshot comes out and go. I ALWAYS use a big fuel filter in the line coming up to carb and the small internal carb filter gets tossed almost immediately, they clog super easy. I do not use the 1/8" pipe thread inlet filter either, always a simple hose fitting there and bigger filter down lower. Clear so I can see if fuel in it.
I feel same way as jeremysdad about priming engine with fuel, one guy only, watched a friend get blown backwards once when doing it, he and girlfriend got tangled up in communications, she turned key at wrong time. BOOM. I've done it a hundred times safely yet I back up when others do it, you just can never tell what someone is going to do there......... ..........seen hair on fire more than once.
I use ether all the time but one concrete hard rule, if it does not light up at all after a solid 2 second shot then STOP RIGHT THERE and find out what is wrong with car. I came up once just as a mech friend was finishing blowing up 6 out of 8 connecting rods in a Pontiac V-8, he kept squirting more and more ether in as car kept trying to barely start, it bit him bad. Block had so many holes in it it was not funny. As I said 6 rods spit in half. Awesome. Turned out he had done a cam change and forgotten to tighten fuel pump lobe to cam, it halfheartedly spun every once in a while to just barely pump a small amount of fuel. Another mech who knew better kept loading up ether in a 289 Ford that was mistimed to not run and before all over, GET THIS!, pulled #1 plug and lit a MATCH to look in cylinder. It went off and the resultant flamethrower jet hit him in face and head, caught them on fire. Same friend who blew up the Pontiac worked for him at the time and quickly threw a winter coat over him to extinguish it, elsewise guy might have died. The guy was a premiere high dollar sprint and dirt car engine builder in Dallas, go figure........ ............
Cars are fun guys but they can kill you in a minute. Far better to think about things for a second rather than just doing them.