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Timing on 1989 Merc 25hp

M

mattyc

New member
"Hi there,

My dads little

"Hi there,

My dads little boat has a longleg 89 Merc 25hp on it, a sweet little motor, starts well and runs well, it seems to be lacking in power, A newly replaced solenoid gave up the ghost the other day so i changed it and noticed the timing advance rod connected to the throttle was wound out a bit at one end, perhaps 40mm - The engine seeems to rev a lot and take a while to get on plane, boat is a 13foot6 figlass. Seems to rev a bit without being torquey - too much timing perhaps ?the transom has been raised so it sits normal depth, and it goes ok once on plane.

my cousin has a 97 30 merc on a 14'6 quintrex and it has a LOT more power and planes easilly on 1/2 throttle"
 
You may have a spun prop. Put

You may have a spun prop. Put 2 marks on the prop. One on the very inner hub and another opposite of it on the out hub so they are lined up. Now go for a ride then recheck the marks. If they are not still lined up have the prop rehubbed.
 
"thanks for the replies guys,

"thanks for the replies guys, engine runs smooth as, both cyls have equal compression, Prop is not spun.

I think the last guy to service it over advanced the timing. does anyone know the factory recommended length of the rod that goes up to advance the timing as you open the throttle."
 
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