View Full Version : Merc 8horse problem
Grant Scheele
10-12-2002, 10:52 PM
My 93' Merc 8 horse won't idle. It runs fine with the throttle open but dies when I try to run it slow. I have changed the plugs and made sure that I have the correct fuel/oil mixture. The idle control is turned all the way up. Any guesses as to why it won't run correctly?
Gone Fishin
10-12-2002, 10:59 PM
It may need to be de-carbed, after a long time of slow trolling speeds it will build up and choke off your exhaust ports. Needs to be taken in for service.
One possibility anyway, I had that problem last year.
-Marty
springer_97011
10-13-2002, 02:18 AM
mine did the same thing but it was the little gasket at the fuel filter was allowing it to lose pressure.it ran fine with a little throttle but would die at idle.about a 50 cent fixf if that is it.if you pump the fuel bulb when it starts dying that is most likely it.
Spoiled Daddy
10-13-2002, 05:45 AM
Good Morning!
I have to agree with Gone Fishin... I had a 86 Merc that I ran for years. I had to have the carb and exhaust ports cleaned twice, as the crud would build up and not allow it to idle.
Simple fix and usually not that expensive.
SD
graybeard
10-13-2002, 09:34 AM
It sounds like the same problem I had with my Honda (4 stroke) this year. It had been sitting for a long time and wouldn't idle. Took it to the shop, had the carb cleaned, now it runs fine. Gasoline sitting in the carb for a long time forms a varnish coating on the carb jets and generally turns to crud.
Merc makes a product called Power Tune. It is a spray that you shoot in the carb after the motor is warmed up. It cleans out all the carbon and coking that builds up in a motor (mine was running too cold). I used it, then switched to hotter sparkplugs, and never had another problem.
Grant Scheele
10-13-2002, 05:12 PM
Thanks for the suggestions. I will get to work. Grant
Kinebra
10-14-2002, 09:25 PM
try an old gamefisher! :grin:
Wet_Willy
10-15-2002, 07:54 AM
Grant,
If you use the powertune spray product that mojo is talking about be careful where the exhaust is pointed. It blows all that junk out of the exhaust and makes for a nasty mess unless you have it in a tank, then it turns the water black.
Bill