More Cowbell

I purchased the US Carb generic kit and installed in my 5kw Kawasaki. Your write-up is what got me thinking of converting my generator to run on Natural Gas. I went with the generic spud-in kit with the assurance from US Carb sales that I wouldn't have to permanently modify my existing carb to have it working. Well, that was not the case and I had to resort to fabricating an adaptor to go between my the air filter and the carburetor. Although I'm willing to forego the tri-fuel, but I'm not prepare to throw away a perfectly good carburetor. Mine, especially is harder to find and very expensive to replace.

My first attempt was a 1-1/4" steel shaft collar from princess auto ($3.99) that I drill the connecting bolt holes. The set screw hole made for a perfect location to solder in a 1/4" brass barb. It worked fairly well but I found with the 1-1/4" orifice, there was not enough venturi suction to engage the KN regulator, and to overcame this, I had to restrict the air flow through the air box by using a jar lid to cover the air spout.

My second attempt was a $1.00 hockey puck that I drill a 1" center hole and enlarge the gas inlet to a 3/8" to accept the full flow from the KN regulator. It's not perfect, but it does create the venture suction as the 1" hole is smaller than the carburetor's throat diameter creating an minor restriction and negative suction through the inlet gas line. The puck works especially well for those that do not have a lathe or any special milling machines. It's easy to work with and is rigid enough to be bolted/compressed and gasket is not required (bonus).

Overall, I was surprised at how simple the conversion is and how one can easily modify their generator to accept propane or natural gas. As for the tri-fuel adaptor, a simple steel shaft collar or hockey puck works just as well. Just make sure that the orifice diameter matches the smallest throat diameter of carburetor (i.e. at the carburetor's jets) and use the largest inlet spud tube as possible. This will require less negative venture suction to activate the KN regulator.

Thanks for the inspiration. I'll post an instructable on my two diy propane conversion adaptor. Cheers!!

KD