Converting OMC Cobra to Mercruiser

[dahm23]

I've got a 1986 Bayliner Capri equipped with OMC 5.0 liter GM Engine and an OMC Cobra Outdrive. The outdrive is hammered...the previous owner tore it apart and left all parts exposed to the weather for years. Many people recommend going to a Mercruiser outdrive because they are more dependable. Is there any truth to this? How do I go about determining what Mercruiser drive unit I need and what ?adapters? I would need to complete the conversion? Know of any shops that could order these parts in and install them in the Albuquerque area?

 

[bigbrownbuku]

Re: Converting OMC Cobra to Mercruiser

the cobra outdrive cutout is far closer to a volvo sx drive and transom assembly. would be easier and just as reliable to go that route.

 

[seahorse5]

Re: Converting OMC Cobra to Mercruiser

The Cobra transom cutout is the same as the Alpha MerCruisers. For the Volvo SX, you only have to drill 2 more holes near the top.

 

[KaGee]

Re: Converting OMC Cobra to Mercruiser

DonS has posted previously of converting to Volvo Dual Prop... with pictures!

 

[rodbolt]

Re: Converting OMC Cobra to Mercruiser

I would convert it to the SX if the engine/transom shield is ok. you will have to add a belt driven or crankshaft driven water pump but thats easy enough. if ya really want to play you can go with a duo prop unit as well.<br /> but the SX is a solid unit and can be purchased as a reman unit for less than new.

 

[Don S]

Re: Converting OMC Cobra to Mercruiser

Volvo sells kits to adapt the SX drive (Or the DP-S if you want duo prop)to the OMC Cobra Transom shields.<br />The kits include a crankshaft mounted water pump, hoses, transom shield pivot housing, bellows, and spacers for the trim cylinders. You also get to remove the ESA system completely as there is no shift interrupt system on the Volvo drives. Single cable from contoler to the drive.<br /><br />Seahorse:<br />Just an FYI, the top 2 holes needed are only if using the 7.4 engines. 5.7 and below doesn't need them.<br /><br />Here is a picture of a DP-S drive I installed on a 28' Bayliner a couple of years ago.<br /><br />

 

[Lou C]

Re: Converting OMC Cobra to Mercruiser

The other good thing about the Volvo conversion, is that you are able to keep the tilt and trim, and steering sytems intact, and only have to change the drive, pivot housing, cables and related parts. Now of course if only Merc service is available where you are, the Alpha conversion would make most sense from a practical standpoint.

 

[dahm23]

Re: Converting OMC Cobra to Mercruiser

I like the ideas tossed around for the volvo drive...it looks like a high speed system but I'm all for the most practical method. So I'm leaning toward the Alpha drive. Where is a good place to order one for a reasonable price. I am willing to buy a strong rebuild. And is there only one Alpha or do I need to look for a specific one to mate up with the original equipment?...Adapter units? Thanks a lot, I hope I'm not too dumb to be helped with this.

 

[Don S]

Re: Converting OMC Cobra to Mercruiser

I don't think you understand. You cannot adapt a Mercruiser drive of any kind to your OMC transom shield. This would mean you need a new Mercruiser inner and outer transom shield, trim setup, exhaust Y setup. New shift setup on the engine, new manifolds, new risers, lots of hoses and lots of little things not mentioned. You just can't get a Mercruiser drive to slap on the OMC transom shield.<br />PS: Those Volvo drives are not the Hi Speed drives, they are the common everyday drive used on everything from the 3.0L engine to the 8.1's.

 

[sea wolf]

Re: Converting OMC Cobra to Mercruiser

It's an expensive proposition in any case. We're talking thousands. Do u want to spend that kind of dough on an '86 Bayliner?

 

[dahm23]

Re: Converting OMC Cobra to Mercruiser

Alright, I'm sorry I'm very new at tinkering with boats. It sounded like a painless process to mount up a merc outdrive the way I heard a guy talking about it...maybe he didn't know. So this Volvo is the way to go? Is there a particular model I should look for to be most compatible? Where do I get one? And yes, I'd like to spend money on the old Capri...unless, of course, I could find a boat just like it in working condition for about the same cost as the repairs on the Capri. It's the perfect boat for what I want to do. I want to cram all my friends in and have the ability to tow a wakeboard and raise the trim to beach it without having to worry about breaking skags such as those found on an actual ski boat. Am I headed the wrong direction?

 

[tommays]

Re: Converting OMC Cobra to Mercruiser

if the hull is sound the transome and other parts have no rot ?<br /><br />then you need to pick a dollar amount your happy spending and see if it will get it done right BEFORE you start <br /><br />you could be droping many thousands of dollars <br /><br /><br />tommays

 

[Lou C]

Re: Converting OMC Cobra to Mercruiser

go over to www.marinepartsexpress.com <br />they have info and prices for the parts needed.<br />Parts wise it is at least $6K and if you can't do it yourself you have to add labor.<br />The rest of the boat really has to be in VERY good shape for this idea to make sense. <br />Only cheaper alternative it to get a rebuilt Cobra drive. Changing to a Volvo will give you something that is easier to get fixed and easier to sell down the road, but you will not get the money from the conversion back so you'd have to like that boat for a LONG time!

 

[Mile-High Mariner]

Re: Converting OMC Cobra to Mercruiser

 

[Flukinicehole]

Re: Converting OMC Cobra to Mercruiser

I dont mean to hijack this post but I just bought a hull equipped with a cobra drive and blown 5.0 engine.I have a 5.0 chevy(305) and mercruiser drive with all cables etc.I havent pulled the mercruiser set up yet but was wondering if the transom hole is the same?If not do I plug the hole completly and start from scratch?Any help would be appreciated.As far as the hull goes there are some great deals out there.If you have a good engine and drive you can get a great hull for next to nothing.No one wants to fix there boats anymore they get a new one with the 20yr. payment.

 

[Don S]

Re: Converting OMC Cobra to Mercruiser

START a NEW thread. DO NOT Hi Jack old threads, especially REAL old threads. You never will get your question answered.

 

[Flukinicehole]

Re: Converting OMC Cobra to Mercruiser

Real old? Last post was 5:39 thats old? Never mind Ill get off now sorry.

 

[Mile-High Mariner]

Re: Converting OMC Cobra to Mercruiser

My bad, too, Don - I accidentally began to post to a thread I found in a Search, without realizing how old it was - but it caught you trolling, didn't it? <br /><br />Flukinicehole - to answer your question, YES, the OMC Cobra was designed to fit in the same transom cutout as the existing Mercruisers, at least the Alpha series Mercs. Incidentally, how much will you take for the Cobra outdrive, and how many hours does it have on it. If you've started another thread, please direct me to it. Thanks!

 

[Flukinicehole]

Re: Converting OMC Cobra to Mercruiser

I didnt start another thread I found the answer my self when I pulled my drive today.Swapped everything over real easy.As for the Cobra drive no I dont have it only the gimbel housing the drive it self was gone. Thanks for replying with a honest answer.That other guy really knowes his stuff but has an attitude problem.