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I have a 2002 mercruiser 8.1 horizon in a cruisers yachts…

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I have a 2002 mercruiser...
I have a 2002 mercruiser 8.1 horizon in a cruisers yachts 3470 express.
The starboard engine starts and idles fine but it will only reach 3500 rpm and in is sluggish. It does not pull as hard as it should. It sounds strong at idle and at run up but under load is a different story. I think I have a fuel pressure issue.
The engine has just had the fuel injectors cleaned and serviced. The injectors were serviced because the engine seemed to exhaust some raw fuel. the company that serviced them said they had a lot of junk in them. The fuel rail was replaced last year. Should they injectors have been purchased new instead of having them serviced? what do you think the issue is?
Submitted: 2 years ago.Category: Boat
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Answered in 4 hours by:
1/31/2016
Marine Mechanic: Jason, Marine Mechanic replied 2 years ago
Jason
Jason, Marine Mechanic
Category: Boat
Satisfied Customers: 18,172
Experience: Degree in Marine Technology. Gas and diesel marine mechanic.
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Hello my name is ***** ***** am I speaking with?

As far as the injectors being new vs serviced, if they were properly serviced they would have also been flow tested. And they would flow test either good or bad. If they flow tested good then there is no reason to buy new ones.

What is the story on this boat? When was the last time the engine made full power? How old is the fuel? Has the engine been compression tested, or the fuel pressure tested under a load yet?

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Marine Mechanic: Jason, Marine Mechanic replied 2 years ago

Hello, just checking in. Did you still need help with the issue?

-Jason

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