Interceptor Conversion to Mercruiser

Vintage Boat Guy

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Hi, I have an old Dearborn Interceptor in my boat, its a 221ci with the Eaton outdrive. I have been reading about others converting the old Interceptors to Volvo outdrives, is it possible to convert to a Mercruiser outdrive instead. I was wondering if a Mercruiser 888 outdrive would be a good candidate because they are usually hooked to 302ci Ford engines which is similar to a 221ci Ford. Has anyone tried this? Is there a better drive system I should look into instead?
 

HT32BSX115

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Hi, I have an old Dearborn Interceptor in my boat, its a 221ci with the Eaton outdrive. I have been reading about others converting the old Interceptors to Volvo outdrives, is it possible to convert to a Mercruiser outdrive instead. I was wondering if a Mercruiser 888 outdrive would be a good candidate because they are usually hooked to 302ci Ford engines which is similar to a 221ci Ford. Has anyone tried this? Is there a better drive system I should look into instead?

Howdy,


Well, yes you could "convert" to anything you like. If the EATON outdrive transom cut-out is different from a Merc (and it is) you would have to replace/reglass the transom and then recut/redrill to match the Mercruiser gimbal mount.

You would also likely have to re-locate the side engine mounts since they wouldn't be in exactly the same place with the Mercruiser transom mount in place.

It would be a major (but not impossible) job to do the transom.

A Volvo SX type drive would be similar. The older Volvo drive might be doable because the Eaton cut-out might be slightly smaller but you'd be going from one obsolete drive to another.

Ford marine engines are also obsolete and it's getting harder to find inexpensive couplers, exhaust manifolds etc.......

If you cannot part with that boat (I.E. it was "Dads" boat and you want to restore it........I totally get that btw!!) .....your best bet would be to find a rotted out or otherwise damaged boat with a good Mercruiser 4.3L (V-6) or 5.0/5.7L (V-8) engine and drive.

Then do a restoration on your "Vintage-Boat" to include the replacement transom. Use the Mercruiser installation manual to re-cut the transom and install the "new" engine and drive. You'll then have a "vintage" boat that has a completely supportable engine and drive that can be sold to someone else in the future that will also be able to service and support it !!


Regards,


Rick
 

Scott Danforth

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part of me says restore what you have, just for the cool factor.

the volvo drive appears to fit better based on my limited searching this morning (I was curious). however as Rick pointed out, get a complete engine and drive assembly if you want to update, and update the whole ball of wax.
 

Bondo

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Ayuh,.... What's wrong with the Dana/ Eaton drive,..??

Swappin' the drive, 'n not the obsolete motor just don't make any sense,...
 

Bondo

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Ayuh,.... Twin Danas on the houseboat,.... 318 Chryslers in front of 'em,....

'n a hyd. clutch on the back of the motors, to shift the drives,..... cable actuated,...

Built like tanks,.... 8 quarts of oil,....

Parts still available from Marysville Marine in Marysville Michigan,....
 

HT32BSX115

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Ayuh,.... Twin Danas on the houseboat,.... 318 Chryslers in front of 'em,....

'n a hyd. clutch on the back of the motors, to shift the drives,..... cable actuated,...

Built like tanks,.... 8 quarts of oil,....

Parts still available from Marysville Marine in Marysville Michigan,....
I thought so. Well, maybe putting a 289/302/351 in front of one might work pretty good in a vintage boat! https://www.youtube.com/watch?v=auaFBxP-YvM
 

Bondo

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I thought so. Well, maybe putting a 289/302/351 in front of one might work pretty good in a vintage boat! https://www.youtube.com/watch?v=auaFBxP-YvM

Ayuh,.... Mine are the hyd. trim model, alittle bigger than that in yer link,....

f13502.jpg
 

Vintage Boat Guy

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The only reason I would keep the engine is because it is original, runs beautiful and the old eaton drive doesn't have power trim. I wouldn't have too hard of a time finding parts for the engine as I would finding parts for the outdrive.
 

Bondo

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In the fall of 1961, when Ford introduced the new Fairlane intermediate coupe, they also introduced the 221 c.i.d. Windsor V8, the same size as the original Ford flathead V8 of 1932. And lightweight it was, at only 450 pounds with the accessories bolted on. But alas, the 221 was a marginal performer at best, so as a stop-gap measure, Ford upped the size to 260 cubes in mid-1962, and the 221 was phased out in 1963,

Ayuh,... That motor was built for barely a year, over 50 years ago,.....

Mercruiser dropped the Ford motors back in the 70s,....

If yer goin' for an "Original" type restoration, go with what ya got,....

If yer doin' an up-grade to a solid power package, in a vintage hull,....
Go with a SBC, 'n Alpha drive,....
 
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