Also, many don’t realize that the J9 has a waterpump impeller to keep the bottom bearing and leg cool. These impellers are often overlooked and it leads to the lower bearing getting fried pretty quickly.
I use air-cooled oil in the ones we have, 16:1. The fuel pump diaphragm is easily made from generic material – you can get it from McMaster Carr or Ollie G. has small sheets available: http://www.pfs-ware.com/Parts/OllieParts.htm It’s just a flat piece of material sandwiched between the two halves of the connector/pump assembly. Punch the 3 holes for the screws and trim the sides, you can make it in a couple of minutes.
