Need troubleshooting a couple Throttle/rpm problems

hernandb_

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Jul 29, 2024
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Final got the boat to run on the water but I have couple issues I don’t really know how to fix. I put an inline Holley electric fuel pump since the past owner said the old mechanical fuel pump isnt working

1) The boat idles around 4000 rpm. But once it’s on the water and if forward gear, it runs okay. Tried using the idle screw but didn’t seem to do anything.
2)The boat only stays within a certain speed. If I give it throttle, It’s not getting enough fuel.
Would adding a regulator work?
3) When trying to shift from Foward back to neutral, it doesn’t want shift into neutral. It gets stuck. When I turn off the engine, then I’m able to shift into neutral. How can I fix this?
4) It shifts hard to get into gear. What can I do it smooth it out?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Jul 23, 2011
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49,554
First, welcome aboard

second, what are you working on? you have to tell us in detail.
Third, is this a new to you boat? or have you had it for a long time?
fourth, anything over 700 RPM is no longer idling
fifth, simply adding an electric fuel pump may have just built a BOMB.
full

did you at least wire it thru a relay and the oil pressure switch.
6th, most likely you need to rebuild the carb.
7th, your shift interupt switch may not be working. most likely this is a mercruiser. and your lower shift cable needs replacing. additionally trying to shift with the motor above 650-700 RPM will eventually take out your outdrive
 

hernandb_

Recruit
Joined
Jul 29, 2024
Messages
4
First, welcome aboard

second, what are you working on? you have to tell us in detail.
Third, is this a new to you boat? or have you had it for a long time?
fourth, anything over 700 RPM is no longer idling
fifth, simply adding an electric fuel pump may have just built a BOMB.
full

did you at least wire it thru a relay and the oil pressure switch.
6th, most likely you need to rebuild the carb.
7th, your shift interupt switch may not be working. most likely this is a mercruiser. and your lower shift cable needs replacing. additionally trying to shift with the motor above 650-700 RPM will eventually take out your outdrive
Thanks for the comment. I am very new to boating.
Its a 3.0 L OMC Cobra on a 1990 Phantom 180.

Boat is new to me. Have been having it for about a year now but havent been able to work on it too much/get it running until last week.
I rebuildt the carb last september.
Wired the fuel pump to a relay and fuse, but not the oil pressure switch.

How much is a lower shift cable cost? Is it easy to replace?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Jul 23, 2011
Messages
49,554
You know a new mechanical fuel pump is about $50 and a properly installed marine J1171 compliant electric pump is almost $100

Check the cable adjustment first. Measure the stroke

You may have to go back to the carb
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Your stock pump is a Carter marine fuel pump
You may be able to even get a rebuild kit.

I recommend avoiding the Chinese parts from Amazon
 

hernandb_

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Jul 29, 2024
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4
How can I check the cable adjustment? Is there a video on YouTube that explains where it should be? If so thanks.

Also I checked the interrupter switch. Just wondering if I need to replace both or just the one that has the roller arm on it?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
49,554
use the search function. @Lou C posted a few times the best way to adjust an OMC cobra.

its also covered in the factory manuals you can order from https://outboardbooks.com/

I would avoid the youtube videos. most of the time, the information is wrong.
 
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