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I have a 1999 75hp mercury motor that is running very rough.

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I have checked compression...
I have a 1999 75hp mercury motor that is running very rough. I have checked compression and it is approx. 100psi on all 3 cyl. I have removed and cleaned all 3 carbs and it did not help. It has new plugs and pulling plug wires one at a time does not show a difference in the miss. Can you help?
Submitted: 3 years ago.Category: Boat
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6/25/2015
Marine Mechanic: Jason, Marine Mechanic replied 3 years ago
Jason
Jason, Marine Mechanic
Category: Boat
Satisfied Customers: 18,193
Experience: Degree in Marine Technology. Gas and diesel marine mechanic.
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Hello my name is ***** ***** am I speaking with? How old is the fuel?Does pushing in on the keyswitch make the engine run better or worse?
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Marine Mechanic: Jason, Marine Mechanic replied 3 years ago
Hello, it looks like you read my response and logged off. Did you try to send a reply back as I did not receive one.
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