1982 25 hp mercury need help

[66shelby]

Have a 1982 25hp mercury outboard. I'm having problems getting it to run smoothly. It has a real rough idle, it smokes and is running to rich. I have rebuilt carb, installed new reeds, compression is @130 in both cyclinders. I've tried to also adjust timing and carb, it helps a little but not alot. I also checked for vacuum leaks with carb cleaner. I have new spark plugs, the coils and spark plug wires check out ok, pulled spark plug wires while running individually and it still ran, didn't die. I stumped on what to do next..Any help would be appreciated..Thanks

 

[jbjennings]

Re: 1982 25 hp mercury need help

Too rich? Do you mean too lean? If it's running too rich, adjusting the idle screw should lean it out.
If it's too lean, the other possibility besides dirty carb or intake/carb vacuum leak would be a lower crank seal leak.
HOpe this helps,
JBJ

 

[66shelby]

Re: 1982 25 hp mercury need help

Where would the lower crank seal be located at. And how could i check if its leaking

Thanks

 

[66shelby]

Re: 1982 25 hp mercury need help

Last night i pumped up my carb and found out the main jet is leaking. Is there a way to repair the main jet
Thanks

 

[jbjennings]

Re: 1982 25 hp mercury need help

Did you use a new carb kit on your carbs? I would guess that your float is out of adjustment on the carb that is leaking, or that the float needle is sticking open.
Main jets don't usually crack or break. It's either a gasket issue, or a float adjustment/float needle problem.
Good luck,
JBJ