[6pack] Hard Starting New SU6 Carbs

[Sally or Dick Taylor]

Steve---The need to use a Choke depends a lot on the temperature of the engine and surrounding temperatures. If you would like to reduce the time the choke is in use, you could just lower the jets on the SU's a couple of flats, or more. This will allow more fuel to pass thru, so the air/fuel mix will be richer. This lowering is easy enough to do, and entirely returnable to where they now are, (if you don't like the results) by counting the number of flats being lowered.

It would be good to know that there are no vacuum leaks, that cause a lean mix, more noticeable during warmup.

Also, feel the intake manifold pipe, to be sure there's (hot) water flowing thru it as the engine warms up. This aids greatly to the fuel atomization process.

There are several ways to check on whether this air/fuel mix is correct. Depending on one's budget and need-to-
know, we can use the simple but not always reliable sparkplug color test, ColorTune, or a tailpipe exhaust analysis, or even an air/fuel analyzer with the attendant 02 sensor. Know that enrichening the mix at idle speed, where it's critical, doesn't change the mix all that much at cruising speeds. There's always the possibility that the needles being used in these SU's are too lean to begin with, but that's for another post!

Dick