My old (1960-70) Sears Suburban, 12hp has been very slow to turn over ever
since I first got it about 5 years ago. It usually starts but you'd think
it hardly turned over once or twice very slowly. I replaced the regular 12V
tractor battery with a car battery but it still turns over slow. It has the
old belt drive starter and I also swapped it with another machine - still
slow cranking. Any ideas as to how to get this sucker to spin over better ?