Re: 120 johnson quick start
Here is a cut and paste from another post involving a 1995 130 HP. It might be the same or similar.
Im curious too as to why the idle timing would affect the top end. A linc n sync is a good place to start as stated per your manual. What type of plugs are you running?? The spark plugs have to be the factory recommended QL78YC. Use of other spark plugs or wires can cause problems inside the power pack. A breakthrough at CDI Electronics has allowed the use of microprocessor digital control circuits to handle the timing, QuickStart, S.L.O.W., rev limiter and data logging inside the power pack. This allows the timing to be set using a timing light, remote starter, spark gap tester, piston stop tool and a jumper wire. With these new digital power packs, you disconnect the port temperature switch/sensor leads and use a jumper wire to short the tan temperature sensor wire to engine ground. Once you have verified the timing pointer using a piston stop tool (Or a dial indicator), connect all spark plug wires to a spark gap tester, connect a remote starter to the engine and a timing light to # 1 spark plug wire. When you crank the engine over with the remote starter and check the timing, you should see the timing is set to approximately 4?-6? ATDC (After Top Dead Center). By advancing the throttle all the way and rechecking the timing for WOT (Wide Open Throttle), you should see approximately 19? - 21? BTDC (Before Top Dead Center) Without this timing feature built into the power pack, you would not be able to easily set the timing for idle or WOT without a optical diagnostic tool. Additional advantages offered by the digital circuitry include the ability to compensate for a bad temperature switch, a smoother rev limit, customized rev limiters and special timing curves.
