Replace 5.0 with 5.8. How to ensure compatibility?

BojanglesIV

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I have a 1992 5.0 OMC Cobra (model: 502BPRAMH) that is seized and needs replacing. I've identified a 5.8 of similar vintage that I'd like to buy, but I'm not looking to do a ton of rework on the swap, Short of actually buying the new engine and starting to install it, is there a way that I can tell from the model number whether it will be a drop in replacement or not?

Any info and reference documents would be welcome.

Cheers
Colin
 

Bondo

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Ayuh,.... Welcome Aboard,.... So long as ya use a 351 Windsor, it oughta be plug, 'n play,....

A 351 Cleveland is No good, nor is the 351 Modified,...
 

BojanglesIV

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Thanks Bondo. How can I tell whether it's a Windsor, Cleveland, or Modified? (And, for my own knowledge, can you tell me why Cleveland and Modified won't work?)

Thanks!
 

Bondo

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Well,.... I ain't a Ford guy, other than I drive a Ford pickup, 'cause I like the Navistar 7.3l diesel motor in it,....

But anyways, rememberin' from years ago, Ford used to used 3 very different 351 motors,....
The 351 Windsor is the small block, used it cars, trucks, 'n boats,...
The 351 Cleveland is a big block used in cars, 'n Hot Rods,...
'n the 351 M is a different big block, that I don't recall what it was used in,...

As I understand it, Externally, the differences in yer 302, 'n a 351 Windsor is the heads, 'n intake manifold,....
The 351 heads are taller, 'n that changes the intake's pattern,....
 

southkogs

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Modified was the truck version IIRC. I'm no expert, but I worked on lotsa' Windsors back when we stupid kids were trying to make LTDs go faster ...

THIS isn't a bad write up on 'em.
 

Silvertip

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Just a quick reminder -- are you certain the current 5.0 is a Ford (distributor in front) and not a 5.0 GM (distributor in back)? GM and Ford don't get along (parts interchange-wise).
 

Lou C

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And OMC used both 5.0 Fords (that were 302 cu in) and Chevrolets (that were 305 cu in).
Taking at look at the OMC parts catalog at Crowley Marine, both the Ford 5.0 and the 5.8 were available that year and the cyl heads for each have the same part number. the engine blocks have different numbers. I think you need someone really familiar with Ford engines used in marine applications to make sure.

http://www.crowleymarine.com/johnson-evinrude/945.cfm?mdl=LTJUUJ

take a look around here and compare part numbers for things like the bell housing, rear engine mounts, front engine mounts, intake manifolds, exhaust manifolds, etc, all the stuff that you might need to reuse, and would want it to fit the new engine, because these parts for Ford marine engines are not common like for GM engines.
 
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