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Question
I have a 1996 Mercury Black Max 3.0 L outboard, carburated which is running to cool. I have replaced the water pump, thermostats, and the temp guage is OK. It will stall at idle after taking the motor out of gear. Have tried to adjust the idle, but that does not seem to help. I think it has something to do with the cooling. Help!
Larry you need to have a good service shop look at the motor. How do you know it is cooling too much? Even if it were it may affect the idle but would not cause the motor to stall. I would be looking at carbon on the pistons, uneven compression and fouled spark plugs from a engine running too cool.
I would be looking at proper fuel delivery, fouled spark plugs, one or more cylinders not firing and mis adjusted linkage for the stalling.
Have the shop do a complete diagnostics including a temperature check first. Then have them set the timing and linkages. Post back if needed.
Jeff
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| Comment | Jeffs Answer was helpful. Since there is a lot of smoke, it most likely is carbon on the pistons. I will have shop look into it. | ||
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Jeff Grigg
Expertise
Can help with most any question related to outboards, high performance, hull repair, rigging, if it floats and uses a motor. From a 9.9 on a aluminum boat to DFI two strokes. Outboard motors are my specialty. I can help with some I/O questions as well. Ratings are the only way we know if we are helping. If you are pleased with the help, please rate us. 20% don't bother reading my answers! If you are not going to read the follow up then why ask? Keep in mind we do this at no charge and are not paid. We do it to help you!
Experience
32 years in the marine business. Own a service facility, in coastal South Carolina certified Master Tech by Johnson/Evinrude, certified Mercury/Force, Tohatsu/Nissan. Former technical director for DMI Pistons. 30 year racing career including 3 APBA Formula V National Championships
Organizations
AMTECH, APBA
Publications Written For
Boat & Motor Dealer, Car Classics, Custom Vans (tech articles), Miami News, powerboat racing column
Awards and Honors
Certified Master Technician Johnson/Evinrude
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