Re: Poor idle
There are special meters that will reveal those measurements but it's unlikely you'll need those expensive pieces of equipment.<br /><br />With the spark plugs removed (all of them), rig up a spark tester whereas you can set a 7/16" gap. If a strong blue lightning like spark jumps that gap on all cylinders, all of the ignition components are in good condition.<br /><br />If the spark appears weak on only a few cylinders, the usual cause is a weak coil or poor continuity in the spark plug wire, or no contunity between the primary and secondary wire within the coil itself. This can be checked with a simple ohm meter.<br /><br />If the spark is existent on both banks and is perfect on one bank, but not on the other bank, that would indicate a stator problem which is usually visible in the form of a cracked and/or leaking stator... easy to spot.<br /><br />If the spark is perfect, or you have corrected it to be perfect and still have a idle problem, and assuming that you have not made any mistakes in the linkages, overlooked anything pertaining to the carburetors, the following may be your problem. But first... just in case the idle air bleed jets in the top portion of the carburetor may have been mixed up with other jets similar in appearance, those jets should be .032 jets which are marked 32 on the jet themselves (OMC #320016).<br /><br />The fuel recirculating valves in the intake manifold should be checked to make sure that fuel/air flows only in one direction... from the inner portion towards the hose connection.<br /><br />Now, various V/6 engines in that year and hp range were known to have either slightly warped intake manifolds and/or block (crankcase) surfaces. This allowed a conflict/crossover of crankcase pressure between cylinders. The simple cure was/is to use a double gasket on the intake to crankcase surface area.