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Mercury 2 stroke 115 'tower of power' prop/hub problem

Ok so here is an update. Its been some journey. I want to share again how/when the problem started. After the boat running great for several outings I maybe overloaded the boat in weight with people and at 3/4 throttle it started losing power and i would have to keep 'bumping' it forward to keep speed. Then i settled on the current problem.

Here is where I am at.

I took apart the carbs again and dunked and soaked for 24 hours even after the recommended 20 mins. I got new gaskets etc and I rebuilt the mechanical fuel pump. I reassembled everything and had a helper on the water. After the soaking of the carbs again I idled great and smooth throttle up until 2500-3000 RPM again with that severe miss. So with my helper keeping it at throttle speed enough to 'miss' and previously removing engine cover I watched what was going on by the engine just as she was keeping throttle where I said to. Then I looked and realized at 'full throttle' only going 3k max and having this miss my butterflies on the carbs were barely cracked nevermind wide open. So I manually with my thrumb advanced the linkage from my top carb and sure enough she started taking off on plane as if nothing happened. It was running a ton better but only when my thumb advanced the linkage to match the throttle position otherwise it would bog down.

So my question is this. On a mechanical pump (on the 86' its the christmas tree looking version' what could of got out of sync? What do I have to link and sync to have the matched fuel pump,throttle and butterflies be in unison. I guess in theory that is what's out of whack but how that even happened is beyond me.
 
Ok I can start another thread. I do not have a manual. Up until this point has been basic trouble shooting and online help....I'm sure the next step is proper timing/linkage procedure. However it idles perfect it's just WOT doesn't open.....
 
So spring is here in Florida with our seemingly 'winter days' fading away. Brought the Merc to a mechanic and before he even looked it over he said that it still had the factory rev limiter (which of course why wouldn't I, I wouldn't of disconnected that). He said that whenever he see's one he usually checks it first as the cause for a lot of issues. I took his word but sure enough by disconnecting it the wires going to it were shot. One was corroded and spliced with a newer wire that was barely hanging on. And we brought it on the water and she jumped right up on plane and not a hiccup. Hope it wasn't a fluke as it has been sitting all winter and was the first ride since last summer where I couldn't shake this issue….but so far so good. Just adjusted the timing to have the idle a bit higher but still in range and not bog when shifting and idling. Contacted a mechanic next door to him who used to race these motors in his heyday and said he never ran them either. I only go to the local islands so over revving just like a car would be users error anyways. Figured I would update you guys. Thanks for the replies.
 
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