Having a peruse and rummage around the carburettor and gas tank, iirc it's a late 60's early 70's Briggs engine with a pulsa jet carburetor, not a vac-u jet as it has two pickups instead of the one. In this a little-too-long video I disassemble it, clean out the needle and seat, and most importantly replace the diaphragm, which was all stiff and crusty. Replacement parts were found on Amazon after carefully trawling through Briggs and Strattons website to find the correct diaphragm.
Watch video Pulsa Jet Carburetor teardown and diaphragm replacement | CarBOOrettor | Rototiller Part 6 online without registration, duration hours minute second in high quality. This video was added by user Wood you Rather 21 December 2023, don't forget to share it with your friends and acquaintances, it has been viewed on our site 47 once and liked it 0 people.