1986 mercury 20 hp

[waldo1]

Hi
my motor has spark on both cylinders but only runs on bottom cylindertried switching coils still runs on bottom cylinder
iis it my power pack!
i need help!!

 

[corm]

Re: 1986 mercury 20 hp

Hi,

Your power pack should be ok.
You may have a chipped reed valve. You can remove your carb and look at the reeds to see if one is chipped or split. About the only other thing would be a bad exhaust plate gasket. They did change the gasket material and it was not much of a problem in later years, but yours could be bad. Look for water on your spark plug.
A bad reed valve can sometimes be seen by a washed or wet looking spark plug. Wet with fuel not water.

 

[waldo1]

Re: 1986 mercury 20 hp

Hi,
Motor run perfect before i put for storage last year.
The first start this year it would't start.Check the reed valve,perfectly shut and looks spotless
Thanx

 

[corm]

Re: 1986 mercury 20 hp

Hi,

Did you figure it out yet?

 

[waldo1]

Re: 1986 mercury 20 hp

Hi!
The problem still exist.I ordered new powerpack(switchbox),If not i will try to change stator.It bothers me that because the motor runs so well the last few years .I will check the exhoust plate gasket.
Maybe the problem is somthing else, but i don't now

Txanks
waldo

 

[waldo1]

Re: 1986 mercury 20 hp

Hi everyone!
The motor is good now.The problem was that before winter i check for water contamination in the carburator.I unsrew the check valve underneth the carb and wen i put it back i mis the small ball.
Tkank you all for help