Hello to all. Please advise timing proceedure and specs for a JD model 510 3 cyl. farm tractor. I.m replacing a defective Roosa Master dist. pump. I believe the original pump may have broke down due to the poor lubricating ability of the new low sulphur fuels. I.m also looking for a good fuel additive that would prevent fuel system damage. Best regards and thanks. This message has also been posted in the vintage section. Serge