I have a 3.75 Briggs, been running about 9 years now with no problem, other than "hard to start" early in life. I too stuck with the recommended "not more than 3 pumps" on the primer and it was a work out. I quickly learned to give it 5-6 pumps, and now it's more often than not a one pull proposition, even after sitting for the off season (about one month here).
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72
'02 CLK320 Cabriolet - wifey's mid-life crisis
2012 VW Jetta Sportwagon TDI...at least its a diesel
Non illegitemae carborundum.