| Need some advice [message #69476] |
Sun, 03 January 2010 14:28  |
docsdad
Messages: 32
Registered: May 2008
Karma:
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Got in our 75 Avion before Christmas to go to my sons house in IL. On starting out found when going up slight grades, the cruise control was having to pull throttle wide open to make it up minor hills. In two occasions, had back firing occur, or firing through the exhaust. Turned around and came back to town. While driving in town, could hear major pinging when I took off from stop lights. Preignition. I left MH here and took my sons Tahoe for the trip. I am back home and have pulled top off HEI, the advance moves fine both mechanical and vacumn, When starting and idling while warming up, I get black smoke and black suet on the ground out of the exhaust. Warms up, choke comes off and it starts and idles ok, but appears rich until choke comes off. Idles a little rough with the choke on, but no major problem. Need some suggestions for directions to go. It is 455 engine, carb, HEI ignition. Have not had problem last fall when I drove and have driven into Augusta several times last fall with no problems. Unit has been sitting in back yard, I start on weekly basis and warm up. Filled with gas just few days before starting on on the trip. Your suggestions please.
Jim Thompson Thomson GA. 75 Avion
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