I recently got a 1962 5.5 hp johnson model CD-19 S. I've got it running, and but it seems to run best with both high and low needle valves closed or close to it. I know the seats or bushings that the retainer nuts push against are missing, though I'm not sure that should matter. I've read here that the low end should be open 1.5 turns and the high end .75. When I do this it idles right down and run rough and usually quits. Even with them both closed it runs okay at high speeds but a little rough at low speeds. Any suggestions on what could be causing this?<br /><br />Sorry about the long post and thanks for any help.<br />Also, the fuel line was missing when I bought it so I put a 3/8" line on there even though I know it's supossed to use a 5/16" line. Could this be part of the problem, maybe not enough pressure in the tank? I have had it on the lake once, and it ran good at high speeds but had trouble getting / keeping it started sometimes.
<br /><br />Have a look at Tom Travis' website where he's fixing up a 5.5hp:<br />