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Thunder Monkey

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I am new to the forum and also new to attempting to fix an outboard. I have a 1988 50 horse force that when I got it had a hole in the top piston. I tore it down cleaned it out really well and cleaned up the cylinder to remove any of the piston material that was on the cylinder wall from the piston. I ended up locatig a used pistion on ebay and put new rings in it and put it back together with all new gaskets and torqued to spec. When trying to turn it over by hand it will turn fairly well with a little effort, but with the starter it is either slow or wont turn it. My starter was bad so i replaced it with a used one from bay from a seller i have bought from before. I am confident he sold me a good stater, is it possibly too tight? Should I take it back apart an have the cylinders bored ?
 
Can you test and see if you can start it with a rope ?-----Were there dowels in the block that have to be lined up with bearings ?
 
Did you try jumping the starter directly from the battery? With jumper cables clamp the neg batt lead somewhere close to the starter on the bracket and then touch the stud on the starter with the posative lead. If the starter spins good you have a bad solenoid or a wiring issue.
 
I will give that a try, I just put the starter on at lunch time then had to go to work so I haven't had a chance to do more. I have rebuilt lots of car engines just not too swift with an outboard but I can't believe I did anything that would keep her from turning over. I can rotate it with a wrench on top and it doesnt feel in a bind.
 
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Make sure the battery is fully charged or just try to jump it with your truck/car. The engine was running lean is the reason it cooked the piston top. If you get it running keep an eye on the spark plugs. If the plugs are burning a powdery white you need to address the overlean condition the plugs should burn a nice toasty brown on the electrode insulator.
 
Take the plugs out and then try the starter?
If that works then the compression might be off?
Do a comp test.
These Forces need even comp on both cyl. to operate right.

The cables make sure they are good, no lumps or twists or bad connectors.
They can unravel where the connector is.
Using a set of battery jumper cables won't work.

There IS a locating pin on your crank bearings.
If the pin isn't in the hole it will turn over but bind.
If you torqued the bolts??then the pins might be smashed in place and need to be filed down so the bearing locating hole fits.

Over on boatsdotnet Mercury parts then open the Force section, find the year and model(all 50's are the same) and find the block pic.
#34 on that is the locating pin.
 
The bearings "float" in the hole.
But if they aren't on the pin it holds the bearing up just enough to bind.

Like I said.Make sure the pin isn't smashed down and it can still fit in the holes.
 
So got it apart and yes I smashed the pin, ordered a new one but havent tried pulling the old out yet. Is it just pusj=hed in, or threaded in? Dont want to mess anything else up on it.
 
Press fit.
Good luck getting it out?????
Don't damage it too much trying to getting it out.
Depending on how bad it is try just filing it down so it fits.
 
If it is soft you drill through it say 1/8".-------Fill with oil.------Use a 1/8 pin and hammer to jack it out.-------Sounds like another wild idea , but it works !!
 
???-----------This is not the first time this mistake has been made.------------I have drilled them on OMC motors and taken them out using oil pressure !!
 
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