Need info on a 307 omc!

[1960Fleetform]

I just bought a 1970s Ebko tunnel hull and found a complete 307 Chevy with an OMC outdrive that I plan on purchasing. This is the model that has the thru hull steering linkage and I believe electric trim/tilt.

My question is how good of an engine and drive is this? Are parts easy to come buy? I believe it's all 1971.

Any information that anybody knows and can pass on to me would be greatly appreciated. I'm familiar with Mercruiser and am lost with OMC. Thanks.

 

[gbeltran]

Re: Need info on a 307 omc!

That drive has been obsolete for 30+ years and OMC has been gone since the 90's. Personally I would not go that route. Parts can be found, but you are not going to drive to the nearest marina and pick them up. They will also be used and old. Why that drive combo aside from the fact that you have one available to you?

 

[Howard Sterndrive]

Re: Need info on a 307 omc!

any 1971 engine (or drive) is as good as the parts that have been dumped into it in the last 5 years.

 

[1960Fleetform]

Re: Need info on a 307 omc!

That is the only reason I'm going this route. The price is right so it seems, atleast for the engine. How much work would it be to hook up a mercruiser drive unit to a 307 chevy?

 

[jerryjerry05]

Re: Need info on a 307 omc!

The actual motors are interchangable.
The sterndrive parts,from the MONSTER hole in the sterndrive to the mounts are gonna be a problem.
I tell people buy what you want but OMC's are gonna cost about 3 times what a Mercruiser is gonna cost then you'll end up with something else anyway..
If you can buy it cheap enough get it for parts to sell on e-bay.Keep the motor as a spare.Then buy the Mercruiser to run.WAY easier to fix and find parts.J

 

[1960Fleetform]

Re: Need info on a 307 omc!

That sounds like a much better idea. The engine alone works perfect, and I'm sure drive will sell well on eBay. Would you recommend an Alpha 1 or pre-Alpha?

 

[zbnutcase]

Re: Need info on a 307 omc!

Alpha, preferably the newer the better! Even Gen 2's are old enough now to pick one up for not much money. (Hint: lot of times far cheaper to buy whole boat with the drive system you want)

 

[wire2]

Re: Need info on a 307 omc!

I just bought a 1970s Ebko tunnel hull and found a complete 307 Chevy with an OMC outdrive that I plan on purchasing. ......

The way I read this, the OMC/Chev was NOT in the boat when you bought it?
What drive was in it?

If it has a "keyhole" shaped hole in the transom, it was probably a Mercruiser.
A larger square (with rounded corners) hole means it had an OMC stringer.
What name is on the shift/throttle lever assembly?

I installed a complete alpha system in my boat a couple years ago (was OMC), here's a link to see what's involved, if you're thinking of going that route.
http://forums.iboats.com/showthread.php?t=225270
It wasn't that difficult. Or costly.

How long is the boat? Keep in mind that a 350 is the same weight as a 307, but with more power.

 

[Fishermark]

Re: Need info on a 307 omc!

For what it is worth, the 307 was one of Chevy's biggest mistake engines. The 305 is better with the 350 being your best option.

That's on the engine side of things.

The outdrive - is this an electric shift OMC? Your plan to part it out is probably your best option - then get a better / more up to date boat.

 

[1960Fleetform]

Re: Need info on a 307 omc!

What I did was buy an old 1970's Ebko tunnel hull set up for an outboard and I found a 307 with an OMC drive for sale and want to transplant that engine into the Ebko. Obviously I'm not trying to make a family boat so constant reliability is not an issue. I don't like how big of a hull in the transom is made by the Stringer, and also just want a newer, easier to work on mercruiser drive.

The stringer is electric shift And it has electric trim/tilt.

I found someone who can supply me with a newer Alpha drive and gimbal assembly for a good price. My question is what all is needed to make this transistion to a mercruiser other than the gimble housing assembly and sterndrive?

Sorry for all te stupid questions, first time actually assembling an I/O!

 

[JoLin]

Re: Need info on a 307 omc!

None of my business, really, but why are you going to the trouble and expense of changing a boat set up for an outboard, to an I/O? Aren't you going to have to modify stringers to accept motor mounts, cut a new hole in the transom in precisely the right spot, $etc, $etc, $etc ?

Sorry, but I don't get it. I do wish you luck, tho

 

[thumpar]

Re: Need info on a 307 omc!

You will need exhaust parts and maybe some cooling parts. I don't know what you will need to actually get them to mate.

 

[Bondo]

Re: Need info on a 307 omc!

I found a 307 with an OMC drive for sale and want to transplant that engine into the Ebko.
My question is what all is needed to make this transistion to a mercruiser other than the gimble housing assembly and sterndrive?

Ayuh,.... You Don't.... If ya wanta use OMC,... Use OMC...
If ya wanta use a Mercruiser,... Use a Merc...

It would be Easier to drop a 1939 flathead Ford motor into a 2010 Volkswagon than what you wanta do...

 

[wire2]

Re: Need info on a 307 omc!

Was the Ebco available in both O/B and I/O back in the day? If so, yours may have stringers in place to accomodate an I/O.
So then all you need to do is locate the X dimension on the transom, center a Merc template, mark & cut. Then bolt everything to it.

When I converted mine to Merc, I first waited for a good deal on a late model Gen 2 outdrive on eBay, then called around to a few Merc dealers, got 1 guy to put a "kit" together for me from his used Merc bins.
He boxed all the individual parts including coupler, trim pump, hoses, cylinders, gimbal, transom shield, and several baggies of bolts and hardware, all labeled as to what it was for. With a service manual beside me, it was a piece of cake.

 

[1960Fleetform]

Re: Need info on a 307 omc!

Yes It did I believe because there are stringers present after I pulled the carpet out.

I scratched the OMC engine and drive idea and located a 302 MerCruiser with an Alpha 1 drive, found a template, and will be starting the install soon. I thought about running an outboard like te boat was designed for, but I think this will be alot more fun when it's all said and done.