Timing v6 johnson

adam171771

Cadet
Joined
Jun 9, 2003
Messages
26
I will be putting my rebuilt 175hp Johnson in the water this weekend and want to be sure the timing is set back to 24 degrees from 28. Is running the engine at full throttle the only way to confirm timing? If so it does not sound like a pleasant task, especially during break-in.<br /><br />Thanks,<br /><br />Adam
 

Dhadley

Supreme Mariner
Joined
Feb 4, 2001
Messages
16,978
Re: Timing v6 johnson

Use a test wheel is the best way. Or on the trailer just far enough in the water to pick up water and let the motor reach 5800 rpm in gear.<br /><br />Good luck!
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: Timing v6 johnson

77.... The following may be of interest to you.<br /><br />(Timing At Cranking Speed 4°)<br /><br />The full spark advance can be adjusted without have the engine running at near full throttle as follows. <br /><br />To set the timing on that engine, have the s/plugs out, and have the throttle at full, set that timer base under the flywheel tight against the rubber stop on the end of the full spark timer advance stop screw (wire it against that stop if necessary). <br /><br />Rig a spark tester and have the spark gap set to 7/16". Hook up the timing light to the #1 plug wire. Crank the engine over and set the spark advance to 4° less than what the engine calls for. <br /><br />I don't know the full spark advance setting your engine calls for, but to pick a figure, say your engine calls for 28°, set the timing at 24°. The reasoning for the 4° difference is that when the engine is actually running, due to the nature of the solid state ignition componets, the engine gains the extra 4°. <br /><br />If you set the engine to its true setting at cranking speed, when running it will advance beyond its limit by 4° which will set up pre-ignition causing guaranteed piston damage! You don't want that to take place. <br /><br />No need to be concerned about the idle timing as that will take care of itself. The main concern is the full advance setting. <br /><br />Be sure to use your own engines spark advance settings, not the one I picked out of the air here in my notes.
 

clanton

Rear Admiral
Joined
Jul 9, 2001
Messages
4,876
Re: Timing v6 johnson

What year engine 77? I agree with what JR and DH said, but the final check should be at full throttle and rated rpms. Some stators will advance at 4 degrees, 5 degrees, and 6 degrees. I would also review the service bulletins for recommended changes by the mfg.
 
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