OMC Cobra to Mercruiser Conversion

[Mr Wubbs]

I have a 1988 OMC Cobra 3.0 motor that has serious cracks and has effected the running so that it has to be removed. I have located a 4.3 Mercruiser motor and drive that is in nice shape. I am wondering what I might do to make this swap work. Could the OMC drive and bellhousing be used with the 4.3 ?

If this could not be done, could the Mercrusier be mounted in the same cutout holes as the OMC ?

The OMC has just been rebuilt, if I could do a total swap I would rather. My only worry is the transom hole.

Thanks

 

[cooter2506]

Re: OMC Cobra to Mercruiser Conversion

Transomhole is the same from what I understand but do you have a stringer to mount the v-6

 

[fyrfightr]

Re: OMC Cobra to Mercruiser Conversion

The cutout hole will not be a problem. Changing to a V engine will require new motor mounts in different locations that you boat may or may not be set up for...

 

[Mr Wubbs]

Re: OMC Cobra to Mercruiser Conversion

I do not have a problem adding the front mounting area, I was figuring the V motor would require added area as well. I can pick up the 4.3 as a complete boat that is trashed hull and interior.
I also concidered putting the 4.3 in front of the Cobra drive that was used for the 3.0 OMC..................I think the complete change would be better.

The Cobra drive was rebuilt and will be sold as the usable parts left from the 3.0 OMC.

 

[Mr Wubbs]

Re: OMC Cobra to Mercruiser Conversion

Are the bellhousings different for the 3.0 and the 4.3?

 

[HT32BSX115]

Re: OMC Cobra to Mercruiser Conversion

I do not have a problem adding the front mounting area, I was figuring the V motor would require added area as well. I can pick up the 4.3 as a complete boat that is trashed hull and interior.
I also concidered putting the 4.3 in front of the Cobra drive that was used for the 3.0 OMC..................I think the complete change would be better.

The Cobra drive was rebuilt and will be sold as the usable parts left from the 3.0 OMC.

Howdy,



Yes, your transom OMC Cobra cut-out is virtually the same as the Mercruiser cut-out. (If you use a GEN II, you'll need to drill 2 additional holes for the 8 stud transom)

I removed an '87 460 King Cobra and installed a '97 Mercruiser 454/Bravo III in the "hole".


You may have to do a little work on the engine mounts but you'll be happy with the swap.

Just make sure that you use everything Mercruiser. I even changed the throttle/shift unit to a new Teleflex CH1700. It probably wasn't required but I love it!

I also sold all the OMC "stuff" for about $3000 when it was all said and done!!!


Cheers,


Rick

 

[Bondo]

Re: OMC Cobra to Mercruiser Conversion

I also concidered putting the 4.3 in front of the Cobra drive that was used for the 3.0 OMC..................

Ayuh,... Don't even Think about it...

It's an ALL, or Nothin' proposition your lookin' at...