omcto mercruiser swap

xltier

Chief Petty Officer
Joined
May 20, 2004
Messages
636
has anyone ever swapped a cobra over to a mercruiser alpha 1 gen 1.have a donor boat but dont know about the size of the hole in the transom.if that is major surgery or not.i have a good boat with a bad omc and a junk boat with a good alpha setup.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: omcto mercruiser swap

As long as you do everything, it will swap. The hole in the transom is the same.
 

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
Re: omcto mercruiser swap

Howdy,

Yes it can be done, I removed a 1987 460 King Cobra and installed a 1997 Mercruiser 454 Bravo III.

You'll probably need to carefully inspect the transom and engine mounting area for rot, and water intrusion. The transom cut-out is the same.

If you install an Alpha Gen II you'll need to drill 2 additional holes since they have 8 studs (Cobra has 6)

Plan on using everything Mercruiser from the the other boat including the wiring harness and shift/throttle cables.

It's pretty straightforward otherwise.


Cheers,


Rick
 

xltier

Chief Petty Officer
Joined
May 20, 2004
Messages
636
Re: omcto mercruiser swap

i am wondering y i would change the wriring harness.i was planning on leaving the motor in thats there.it a 4 cylinder chev.thats runs great.i was gonna do bell housing-transom plate-exhaust pipe- gimbal housing and outdrive.alph 1 gen 1.shift interupt plate.not sure on the trim pump.
 

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
Re: omcto mercruiser swap

You could probably use the OMC harness. Depending on the year there may be more pins in the Merc harness.

I used the Merc harness in mine because I wanted to rewire the boat anyway.

The Cobra engine harness might work but you'll have to remove the ESA and rewire it anyway. I would completely rewire the engine if you don't have a usable Merc engine harness.

You'll need to use the Merc trim pump. (you might be able to use the OMC pump but I wouldn't waste my time trying to make it work)

Also, take the time to clean up the engine compartment and maybe splash a little paint in there.

Here's a before and after picture...

I've posted these pictures so many times I think everybody is getting tired of them:rolleyes:

Before
dscn0666.jpg


After
new1.jpg
 

xltier

Chief Petty Officer
Joined
May 20, 2004
Messages
636
Re: omcto mercruiser swap

Nope,... It's ALL or Nothing...

i am really interested y the motor cant be reused.my thinking is that all the dash and other electric is matched.gauges-charging etc.thanks for the replies.
 
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