75hp merc timing/sync

So I just bought a fishing boat from a elderly man who was the original owner and only used the boat a dozen times, literally brand new. The engine is a 98' 75hp elpto 2 stroke. It ran good except it sneezed when starting and idled like crap. I did the normal stuff, fresh gas, new plugs, rebuilt all the carbs, rebuilt the fuel pump, adjusted the air screws etc. I couldn't get it to run any better so I bought a oem mercury manual and did the "link and sync". In order to get the roller and throttle cam white lines to match up took quite a bit of adjusting the idle stop and throttle cable. All seemed good until the last step, timing. The idle timing was in the ballpark where I needed it 5°btdc (obviously will have to adjust to get the idle I want). The issue came when I times the maximum timing, factory setting where the paint is on the adjuster read 27°. Should be 20° at cranking speed so I adjusted the adjuster. In order to get the maximum timing set I almost bottomed out the adjustment screw. Something feels off, I am nervous something isn't quite right. Any ideas? Thanks!

That 27 degrees is there for non-running timing of the motor with a light (the way the factory does it. Running timing is the 20 degrees.)

I remove the carb linkage to the throttle when I time a motor. That lets me take my time and get it right, for the motor only hits about 3 grand with the throttle wide open.

Jeff

fastjeff said:

That 27 degrees is there for non-running timing of the motor with a light (the way the factory does it. Running timing is the 20 degrees.)

I remove the carb linkage to the throttle when I time a motor. That lets me take my time and get it right, for the motor only hits about 3 grand with the throttle wide open.

Jeff

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Ok now im lost. The manual says to statically time the engine to 20° at cranking speed and the ignition with adjust it to 18° at 3000 rpm. So in theory if it was 27° before I adjusted it at 3000 rpm it would retard to 25°, which is way to advanced. Am I missing something?

This cranking timing is so far off, not even close. Should I just do a WOT check of the timing, set it at 18° and be done with it?

I like to play it safe, so I set mine just under the factory timing with a light (using the method I described above). My triple is supposed to be at 23 degrees (WOT) so I set it about 21.5 to 22 degrees.

Jeff

You set it at 20 degrees cranking and it will advance to 27 at WOT....

Or is it visa versa?

Jeff

I set it to 20° cranking, brought it to the lake with the light and did a WOT check, it was dead nuts 18° which the engine is supposed to be at. So why would the factory set it at so far off? Now im getting a surge/miss at wot. Getting really frustrated with this thing.

Can any merc techs chime in? I just got it back from the shop. Had them sync the carbs and time the engine. It came back exactly how it left, still has the bog intermittently when running wot and the max speed timing is exactly the same. Factory static timing it read 27 degrees, can anyone confirm that 27 degrees is safe to run? The manual says 20 degrees and I don’t want to burn it down. This is getting ridiculous....