Problem with my classic 50 (45)

[j-6]

I have had this problem with my motor for a long time now. I asked a couple of mechanics for some direction but nothing in depth came from that. Here is the problem - I pump the bulb a couple of times use the choke and it starts right up. It idles fine I put it in gear and it stays running fine I let it warm up for a little while, then I throttle up and I can not even get on plane, It will run like this any where from 2 minutes to 10 minutes then poof! the engine will take right off, the boat will go on plane and run fine (most of the time). Some times it will bog back down again for a little while the run fine again. I do not use the boat alot, maybe 10 times a summer but it happens every time.

any ideas?

 

[Selcorunner]

Re: Problem with my classic 50 (45)

Try this:
Could be dry lubrication of the unit adjusting spark advance. It is supposed to turn ( up to the stop setting of max spark advance) when you accelerate. If dry, the spring pressure will not be enough to move it until the engine has heated up the old lube. Thats why it will be ok after 15-20 minutes.
At least thats what happened to my 1980 merc 50 hp which is almost identical to yours.

Selcorunner
Oslo
Norway

 

[j-6]

Re: Problem with my classic 50 (45)

excuse the ignorance on my part, I dont know what the spark advance looks like and how do I add lube?

thanks