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I have a Mercruiser 8.1 496HO Pretty much everything is

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I have a Mercruiser...

I have a Mercruiser 8.1 496HO Pretty much everything is brand new from last year mercruiser reman block, oil cooler, heat exchanger, plugs, wires, starter, belts, tcs sensor, feul injectors, etc... my problem is my boat engine will "surge" when in idle to 1200 rpms any suggestions???

Submitted: 11 months ago.Category: Boat
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Answered in 11 minutes by:
9/9/2017
Marine Mechanic: Matthew John, Marine Mechanic replied 11 months ago
Matthew John
Matthew John, Marine Mechanic
Category: Boat
Satisfied Customers: 69
Experience: Marine Technician, Certified in MERCRUISER AND MERCURY OUTBOARDS (Current), EVINRUDE, SUZUKI, YAMAHA, HONDA.
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Hi my name is***** to Just Answer ! I will be assisting you.

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Marine Mechanic: Matthew John, Marine Mechanic replied 11 months ago

Hey ya, just wondering if you had previous issues with performance?? Where are you operating the vessel? Off Shore Cruising? Do you have a DTS system? Digital Throttle and Shift Control... Have you installed new In-Line Fuel Filters? What temperature is the engine running at these speeds? Was the engine commissioned after the install with any special notes or any performance data taken, e.g., Prop size, drive ratio, and do you have or most importantly able to get the maximum RPM's ?

Regards,

Matt

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Marine Mechanic: Matthew John, Marine Mechanic replied 11 months ago

Hi, sorry if it looks like too many questions for you at once! By the sounds of things, you have been over most things that can possibly come to mind and we are here to trigger ideas and thoughts that contribute to diagnosing or eliminating.

As I am thinking of things and coming off live, I will leave one of the mast important things with you, that is the maximum RPM value that the boat will achieve with a full tank of gas and fresh water (full load) and we can take it from there OR with anything else you may think of whilst we can brainstorm your situation. Thanks!

Regards,

Matt

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Marine Mechanic: Matthew John, Marine Mechanic replied 11 months ago

Hi there,

Just a quick follow-up to see how you went...

Please don't hesitate to let me know of any concerns you may have in the future!

Be sure to hit my Star Rating ! ! ! ! !

All the best!!!

Matt

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Matthew John
Matthew John, Marine Mechanic
Category: Boat
Satisfied Customers: 69
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Experience: Marine Technician, Certified in MERCRUISER AND MERCURY OUTBOARDS (Current), EVINRUDE, SUZUKI, YAMAHA, HONDA.

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