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I think I am running rich cause there is a strong gas smell and I have black smoke (only a little) coming through the tail pipes. Any guidelines on adjusting the 400-4 carb on a 67 GS400 TH400? I am really looking for better mileage too.

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Best I can do ya is the proper (best imo) way to set the idle mix.. Buy, borrow or steal (umm, maybe not? wink.gif" border="0 ) a Vacuum Gauge. Hook the gauge up to manifold vacuuum port turn each screw in then back out about 3 turns. Start car, if it refuses to start, up the idle speed a bit. With everything running, one at a time, turn the idlemix screw in until vacuum starts dropping on the gauge, then start turning out until you reach max vac reading on the gauge for that screw. Do the otherside the same way. When done, reset the idle speed and your done. Some (most?) people say to turn the screw in 1/4 turn after reaching highest vac for lean-best-idle but well, it's upto you. I usually don't, but thats me.. lol<P>If she smokes when ya dig into the secondaries might go discount hunting at your local yard for some free rods and hangers.. Just make sure the carb is pre 75 (i forget exact year) as they changed the secondary rods and are not interchangable between the two.<P>HTH<P>Scott

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