Replacing blown OMC outdrive with other brand outdrive?

Denwa

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We have an 1985 Malibu Cuddy with OMC (chevy) 5.7L engine and OMC outdrive.

The outdrive is toast. Seems fixing these is really expensive so I am wondering what one has to do to replace the OMC outdrive with a mercruiser or other brand? Looking for the most economical solution.
 

LAC_STS

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Howard Sterndrive

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Re: Replacing blown OMC outdrive with other brand outdrive?

most economical is fixing what you have.

There are no compatible conversions available for a 1985 OMC.
SEI only sells kits for the 1986 and later Cobra drives

You would need to gut the boat, rebuild the transom with wood and fiberglass, then recut for Mercruiser and buy a complete repower package...probably $15,000+ for a professional refit
 

LAC_STS

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Re: Replacing blown OMC outdrive with other brand outdrive?

Oh yea didnt see the 85 part.

SEI says "Replace 1986-1993 Cobra drives that shift in the lower unit."

Maybe you could call them and see what they say.
 

Bifflefan

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Re: Replacing blown OMC outdrive with other brand outdrive?

We have an 1985 Malibu Cuddy with OMC (chevy) 5.7L engine and OMC outdrive.

The outdrive is toast. Seems fixing these is really expensive so I am wondering what one has to do to replace the OMC outdrive with a mercruiser or other brand? Looking for the most economical solution.

They are all expensive in some sort.
There is kit to replace some of the OMC drives with a MERC one, but I dont know who makes them, and I think they are for a Cobra drive to MERC swap.

You can always pull the drive and motor, redo the transom and cut it for a MERC. Just depends on your ability and how deep your pockets are.
 

LAC_STS

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Re: Replacing blown OMC outdrive with other brand outdrive?

http://sterndrive.info/


These people have a service that you can send your drive in and they will fix it for you. They also sell remanned OMC drives.
 

Denwa

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Re: Replacing blown OMC outdrive with other brand outdrive?

They are all expensive in some sort.
There is kit to replace some of the OMC drives with a MERC one, but I dont know how makes them, and I think they are for a Cobra drive to MERC swap.

You can always pull the drive and motor, redo the transom and cut it for a MERC. Just depends on your ability and how deep your pockets are.

Not very deep pockets. This is actually my Parents boat and t hey are retired and just spent money on reglassing the motor mounts. Trying to find a cheap solution and regardless will probably have to wait till next year to fix due to cost.

Oh yea didnt see the 85 part.

SEI says "Replace 1986-1993 Cobra drives that shift in the lower unit."

Maybe you could call them and see what they say.

I sent them an email. Will hopefully hear something Monday.

Why oh why did this boat have to have an OMC leg. <sigh>. Nice boat in excellent condition otherwise. Leg was inspected last year and was said to be fine. Towed some people on a tube and heard a squealing noise with a noticeable drop in RPM. Putted back to the boat launch and checked leg oil. It was foamy white/green.

Mechanic says upper and lower are "a mess".
 

LAC_STS

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Re: Replacing blown OMC outdrive with other brand outdrive?

Maybe you can try to troubleshoot it.

If you take the drive off then pressure test it. See where its leaking water from.

The manual says how to do all this and how to replace whichever seal is bad.

The manuals are not available here any more but I have them if you PM me your email I will send them to you.


Who knows what the mechanic means by a "mess" he could just mean because of the watery oil. Who knows.

I say take it off, pressure test it, find out where the leak is, fix the seal causing the leak, put fresh fluid in it, put it back on the boat, see if it works good.



You can also remove the lower oil drain plug and check it out. It is a magnet and if you have some serious problems like gears are bad or something it should have a ton of metal particles on it.
 

Denwa

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Re: Replacing blown OMC outdrive with other brand outdrive?

Maybe you can try to troubleshoot it.

If you take the drive off then pressure test it. See where its leaking water from.

The manual says how to do all this and how to replace whichever seal is bad.

The manuals are not available here any more but I have them if you PM me your email I will send them to you.


Who knows what the mechanic means by a "mess" he could just mean because of the watery oil. Who knows.

I say take it off, pressure test it, find out where the leak is, fix the seal causing the leak, put fresh fluid in it, put it back on the boat, see if it works good.



You can also remove the lower oil drain plug and check it out. It is a magnet and if you have some serious problems like gears are bad or something it should have a ton of metal particles on it.

Unfortunately by "mess" he meant the gears in upper and lower. Estimated repair was $4000.
 

LAC_STS

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Re: Replacing blown OMC outdrive with other brand outdrive?

You can prob find a new drive for less than that.

SEI's site says 86 but maybe your boat has the 86 drive.

I think what it comes down to is if it shifts in the lower end.


If its still there grab the model number off of the drive. Mine has a metal plate on the port side of the upper housing that has the model, serial, and engine size.


Post what you find.
 

duped

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Re: Replacing blown OMC outdrive with other brand outdrive?

Doubtful. I've seen '86 boats that still had 85's leftover stringers on them. Usually the engine is either the same year, or one behind the boat's year.

If your drive has a big rubber boot around it, the only answer is rebuild your transom and cut a merc hole in it. SEI will tell you the same thing.

Just browse craigslist. Good used drives can be had for 200-400 bucks. Good luck!
 

Gary H NC

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Re: Replacing blown OMC outdrive with other brand outdrive?

If it has the big rubber boot around the drive then it is an 85 Stringer drive from OMC.No way a Cobra was put in an 85 boat unless it was very late in the production year then still very doubtful.
No new replacements out there period!
Ebay would maybe find you one but that is a gamble as to what condition it is in.

You could find a donar boat with a good engine and drive but that would take a lot of fiberglass work to close the hole in on the transom.
 

Denwa

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Re: Replacing blown OMC outdrive with other brand outdrive?

It has the big rubber boot. :(
 

wire2

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Re: Replacing blown OMC outdrive with other brand outdrive?

If you heard squealing, and then lost rpm, there's a good chance it's failed bearings. I had water in the upper of my '84, the input bearings welded together, stalled the engine. I found out after, the housing had a crack between the gearcase and water passage. (I neglected to check the oil for several years, Duh! A seal failed, let some water in, then froze.)

I had a good used upper case, got all the upper bearings and seals through a "connection" at a bearing supply house for $85, paid a marine tech $250 to change it and all was well again. After that, I meticulously checked the gear oil every fall.

A couple of years ago I replaced the outdrive, mid drive and trim parts with late model Merc Alpha. It's not all that much trouble if you plan ahead. Here's some pics and write-up;
http://forums.iboats.com/showthread.php?t=225270

I sold my OMC parts (Leg, mid drive, trim pump & cylinders, steering, all were in good working order) for $2500, got a 1 yr old Merc outdrive for $1100, all the other bits for $900, Seacast was ~$300 so not counting my labor, I sort of broke even. I kept my 5.7 engine

I strongly recommend that you take out one of the lower stainless screws from the boot, push a small slot screwdriver in the hole at 45?, and see how far you can push it in. If it goes more than ?", the transom is rotten, like mine was.
 

eschober

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Re: Replacing blown OMC outdrive with other brand outdrive?

Not very deep pockets. This is actually my Parents boat and t hey are retired and just spent money on reglassing the motor mounts. Trying to find a cheap solution and regardless will probably have to wait till next year to fix due to cost.



I sent them an email. Will hopefully hear something Monday.

Why oh why did this boat have to have an OMC leg. <sigh>. Nice boat in excellent condition otherwise. Leg was inspected last year and was said to be fine. Towed some people on a tube and heard a squealing noise with a noticeable drop in RPM. Putted back to the boat launch and checked leg oil. It was foamy white/green.

Mechanic says upper and lower are "a mess".
hi .. many places around.. try this one www.twincityoutboard.com/
 

Denwa

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Re: Replacing blown OMC outdrive with other brand outdrive?

Would the transom need to be replaced if a Volvo-Penta leg/transom mount were used?
 

Don S

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Re: Replacing blown OMC outdrive with other brand outdrive?

Would the transom need to be replaced if a Volvo-Penta leg/transom mount were used?


The transom is to thin and the hole to big for ANY other outdrive.
 
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