Omc to Volvo Penta

Rranger

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Does the transom have to be reconfigured to convert from omc to Volvo Penta power and outdrive, or are the transom holes compatible. Or is there some kind of conversion kit?
 

Bondo

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Re: Omc to Volvo Penta

Ayuh,... It'll depend entirely on what Vintage OMC, 'n what Vintage/ Model Volvo....

Nope,... No kits...
 

Don S

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Re: Omc to Volvo Penta

Depends on which type of OMC, and which type of Volvo.

The SX style Volvo will fit the OMC Cobra cutout.
 

Rranger

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Re: Omc to Volvo Penta

The omc is in a 1977 Campion boat and looks to be original equipment. 351 ford with cobra outdrive. I would take it out and stepfather has a older Izuzu diesel with a volvo penta drive. I haven't been able to get serial numbers off the Izuzu or drive so don't know much about the vintage.



Depends on which type of OMC, and which type of Volvo.

The SX style Volvo will fit the OMC Cobra cutout.
 

Bondo

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Re: Omc to Volvo Penta

The omc is in a 1977 Campion boat and looks to be original equipment. 351 ford with cobra outdrive.

Nope,... A 77 will be a Stringer drive, Not a Cobra....

You'll be fillin' the transom in, 'n recutting...
 

Rranger

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Re: Omc to Volvo Penta

Depends on which type of OMC, and which type of Volvo.

The SX style Volvo will fit the OMC Cobra cutout.







And if its a stringer outdrive, is it a transom overhaul job to convert to the sx?
 

Don S

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Re: Omc to Volvo Penta

Yes, not only is the hole to big with the OMC, but the transom is also too thin.
 

Rranger

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Re: Omc to Volvo Penta

Sorry one last question. Are the cobra and Stringer holes compatible?
 

wallerus

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Re: Omc to Volvo Penta

The Cobra and stringer mounts are completely different animals. The model year you have should have a stringer mount. It's super easy to tell. The stringer mount has a big square rubber gasket that seals the outdrive to the boat. This is because as the name implies, the stringer mount is totaly mounted to the stringer inside the boat and not attached to the transom. The Cobra is mounted to the transom via a transom plate. The expense to change a boat to a transom mount from a stringer mount is very high. Last estimate I had for the transom work was $2500 and the didnot include the new wiring, steering, control lever or cables.
 

Bondo

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Re: Omc to Volvo Penta

Sorry one last question. Are the cobra and Stringer holes compatible?

Nope,... The Stringer drives are a breed all their own...

The Cobra drives use what's now the industry standard cut-out, which is the Mercruiser design...
 

wire2

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Re: Omc to Volvo Penta

This is a stringer hole;
boat006.jpg

This is a Merc/Cobra hole;
boat040.jpg
 

Rranger

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Re: Omc to Volvo Penta

Another question from a newbie. Looked at a buddies 6 cylinder inline chev engine with omc outdrive to replace my 8 cylinder Ford engine and OMC outdrive. Both 70's vintage. Unfortunately I didn't have a tape measure with me. But the distance from the transom to the front motor mount on the six banger exceeds the length of the stringers in my boat by approximately 8 to 12 inches. Am I sol for finding a six cylinder to fit the stringers in my boat?
 

Bondo

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Re: Omc to Volvo Penta

Am I sol for finding a six cylinder to fit the stringers in my boat?

Ayuh,... Unless you figure out how to do fiberglassin' work,...
You're pretty much SOLuck, Anyways....
 

Rranger

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Re: Omc to Volvo Penta

Ayuh,... Unless you figure out how to do fiberglassin' work,...
You're pretty much SOLuck, Anyways....







I have done some fibreglass work. Did a inboard to out board transom overhaul and a couple of floors. Is it recommended to add a approximate 8 inch piece of stringer or totally replace it. Assuming the transom hole lines up with the new engine and old stringer height. If it doesn't then a total replacement would be in order. Can I lengthen my boats stringers if done properly rather than a total replacement.? Any tips would be appreciated if its possible.
 

Bondo

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Re: Omc to Volvo Penta

Can I lengthen my boats stringers if done properly rather than a total replacement.?

Ayuh,... This has been covered, 1000s of times over in the Restoration Forum...
 

Don S

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Re: Omc to Volvo Penta

Moving this thread to the Restoration forum.
 

oops!

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Re: Omc to Volvo Penta

hi......welcome to the restoration forum.
dry dock.....as we call it :)

i see our guys have you well informed......cheers to them.

you will need to do a total transom job.....(dont worry....not hard....just time consuming)

you will also have to determine stringer height.

2 ways to do that......after the transom job and the hole is cut. bolt the mounting plate on the transom and hang the motor in the boat with the mounts and isolators.

that will give you the stringer height.

the above is bondos way.....(its the easy way....there for...its cheating :D;))

the other way.....is to measure with out your transom installed or cut. (the process you use will deterimine the method of measurement)

determine crankshaft centerline from the outside of the boat....(we can cover how you do that later)
then ....determine distance from the bottom of your motor mounts AND isolators to the crankshaft centerline. (the center of your bottom pulley on the motor)

then it is easy to determine stringer height from the bottom of the hull.

the tolerance will be the height of the isolator threaded area.....uasually about 2 1/2 ins.

if your current stringer config is too high....just cut a chunk out and glass it with heavy glass.

in the link below.....is a complete motor cage/transom job.
it also has valuable fiberglassing info if you need.

cheers
oops
 
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