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I have a mercury 80 hp outboard that idles rough. I have…

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I have a mercury...

I have a mercury 80 hp outboard that idles rough. I have rebuilt the carbs, ohmed out all ignition components, and ran a fresh mixture of fuel through it to try isolating the problem.

Mechanic's Assistant: Sometimes boat issues seem like they'll be really complicated, but end up being easy to fix. The Marine Mechanic I'm going to connect you with knows all the tricks and shortcuts. Tell me a bit more about what's going on so the Marine Mechanic can help you best.

It idles rough. I just bought the boat about 4 months ago, so I've never had this boat on the water yet.

Mechanic's Assistant: Is there anything else important you think the Marine Mechanic should know?

Well, as I stated, I've done a complete test on the ignition system and it checks out fine. I've rebuilt all 3 carburetors, and I've ran a fresh mixture of fuel through it looking for a difference in its performance, but no luck. I will say that when I open the fuel mixture screw on the top carburetor to equal out with the other two, it starts running even rougher. It seems like there is a problem that is linked to the top carburetor.

Submitted: 4 months ago.Category: Boat
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Answered in 2 minutes by:
3/16/2018
Marine Mechanic: Jason, Marine Mechanic replied 4 months ago
Jason
Jason, Marine Mechanic
Category: Boat
Satisfied Customers: 17,881
Experience: Degree in Marine Technology. Gas and diesel marine mechanic.
Verified

G​ood morning, my name is ***** ***** am I speaking with? I read what you wrote. Mercury outboards are cataloged by serial number, can I start by getting that number so I can see exactly what you have.

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Marine Mechanic: Jason, Marine Mechanic replied 4 months ago

d​id you have that serial number or no?

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Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

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