Switching omc to mercruiser complete set up

[Canamxmr1000]

I have a 1988 four whinns... Right now it has a omc cobra with a Chevy 305 in it... I bought an engine and out drive together that is a mercruiser set up with 20 hours on it. It is the alpha one with a Chevy 305 as well. What is it going to take to switch them out completely? Or am I going to be better off just switching just the engine? I'm sure this has been touched on and yes I have read till I can't see straight. But I have someone coming to help me in two days and really want to know if switching everything is feasible. My main questions are wiring...controls... And will it mount up in the same hole? Thank you in advance for your input!

 

[Canamxmr1000]

Oh and the reason for the switch is not winterizing properly busted the block on the omc

 

[Scott Danforth]

unbolt everything OMC from inside and outside the boat

drill the 2 extra holes in the transom for the Alpha 1 transom shield

bolt in everything Mercruiser.

the longblock is the same between the two (both GM 305 motors), however it is the rest of the stuff that makes it a Mercruiser or OMC.

 

[Canamxmr1000]

Ty for the quick reply. I did not get the controls with the mercruiser. Can I use the omc controls and wiring? Thank you again. The hole not being a problem is a big weight off

 

[southkogs]

... Can I use the omc controls and wiring?

Possibly: remote controls are technically an "accessory." Depending on how the particular remote works, it may swap over fine (I'm not sure what exactly you need). However, you can find new ones HERE.

 

[skippy2235]

I just did the cobra to mercruiser swap.
Mercruiser shifter moves opisite directions then OMC. meaning fwd in omc would = rev in mecruiser. so you need to reveres the cables. easily done.
Need a controller that has more throw at cable connection points. meaning your handle controller needs to have an 2 places to connect cables to going the same direction. omc = mountings close to center of handle, Mercrusier = mountings farther away from center of handle.
I hope you understand this.
I would also change shifter bracket to mecruiser.

With all this big change I think I would change all things to mercruiser. Shifter, cables, brackets...

 

[Canamxmr1000]

Ty skippy! We got the omc out today. Thanks to some awesome help. Mounted the transom plate with no drilling and no problems. I have to change the oil pan and then will be ready to drop the merc in. The plugs seem to be exactly the same too which is some more good news. I do understand reversing the cables. Thanks again all of you guys for your help. Hopefully back in the water soon.

 

[skippy2235]

Now you have engine out, Replace the oil pan plug with a 1/4 turn valve and put a hose on the nipple.
when changing oil, you reach under engine and feed hose through bilge plug hole and then twist the 1/4 turn and drain the oil into a bucket. No more pumping with drill. and you get all the water and oil out.
they sell them on ebay. something like this. find your size and shape you need.
http://www.ebay.com/itm/F106N-14mm-...PLE-/270583792974?hash=item3f000d054e&vxp=mtr

 

[Scott Danforth]

make sure to properly align the engine and drive when done. directions in the stickies at the top of the forum

 

[Idlespeedonly]

If you have the OMC controls you will probably have to replace them. I dont think I have ever seen one that the throw could be reversed on.