Boat

Boat engine 2000 Mercruiser horizon 7.4. Mpi3 runs fine

Customer Question
until 2500 rpm no power...
until 2500 rpm no power. Checked compression injectors cleaned with sea foam on intake line no codes timing ok fuel filter ok fuel ok used dummy tank .Changed cap rotor iac throttle position sensor
and igntion control module. Marina tech hooked up computer checked ok no codes .Fuel pressure ok Checked tranmiission fluid and sensors .Even... Read full answer
Boat engine 2000 Mercruiser horizon 7.4. Mpi3 runs fine until 2500 rpm no power. Checked compression injectors cleaned with sea foam on intake line no codes timing ok fuel filter ok fuel ok used dummy tank .Changed cap rotor iac throttle position sensor
and igntion control module. Marina tech hooked up computer checked ok no codes .Fuel pressure ok Checked tranmiission fluid and sensors .Even swapped engine computer engine to engine no change .We're stumped
Submitted: 3 years ago.Category: Boat
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Answered in 8 hours by:
7/14/2015
Marine Mechanic: Jason, Marine Mechanic replied 3 years ago
Jason
Jason, Marine Mechanic
Category: Boat
Satisfied Customers: 19,700
Experience: Degree in Marine Technology. Gas and diesel marine mechanic.
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Hello my name is ***** ***** am I speaking with? Does the alarm system work in the boat, when you turn the key to run, does it beep each time? What does each cylinder read for compression? Did you check fuel pressure at idle, or with the boat at the highest speed it can hit?
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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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