Will a 78 lower unit work with an 86 outdrive?

ggrace boater

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I have a 78 hydromechanical foot from a model #981918 outdrive that came behind a 78 ford 240hp engine and I need to know if it will fit a 86 V6 4.3 model #984210 outdrive.
 

ggrace boater

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Re: Will a 78 lower unit work with an 86 outdrive?

With a modification it will work right?
 

Boomyal

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Re: Will a 78 lower unit work with an 86 outdrive?

With a modification it will work right?

At minimum, you will need the hydro-mechanical shift converter along with the hydro-mechanical shift cable that is attached to the drive. Otherwise it will bolt right up. I am not sure about the gear ratios and the hydro-mechanical does not use a shift interrupt mechanism.
 

jerryjerry05

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Re: Will a 78 lower unit work with an 86 outdrive?

No.Compare the parts diagrams.
 

Boomyal

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Re: Will a 78 lower unit work with an 86 outdrive?

No.Compare the parts diagrams.

Care to elaborate jj? The hydro-mechanical and full mechanical uppers are the same.

EDIT: I just realized that the poster is talking about mating a stringer lower to a not-stringer upper? I believe that 1985 (split year) was the last year of the stringer drives. If that is the case, then forget the match-up.
 

jerryjerry05

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Re: Will a 78 lower unit work with an 86 outdrive?

The 86 is the Cobra drive.Way different.
 

ggrace boater

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Re: Will a 78 lower unit work with an 86 outdrive?

The 86 is the Cobra drive.Way different.

I'm asking this for somebody else, supposedly Stringer did make an outdrive behind a 4.3 in 86 is what they tell me. I read somewhere that you have to use the mechanical shift cable and modify something in the shift cap or something. Here is the link where I found that, but I haven't found any info on an 86 Stringer beside the person telling me they are for sure it's an 86 Stringer.

OMC Sterndrives - OMC Outdrives - Cobra Sterndrives - Crowley Marine

According to that link putting a hydromechanical foot where a mechanical one went involves using the mechanical shift cable and making a change in the shift cap.
 

Boomyal

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Re: Will a 78 lower unit work with an 86 outdrive?

I'm asking this for somebody else, supposedly Stringer did make an outdrive behind a 4.3 in 86 is what they tell me. I read somewhere that you have to use the mechanical shift cable and modify something in the shift cap or something. Here is the link where I found that, but I haven't found any info on an 86 Stringer beside the person telling me they are for sure it's an 86 Stringer.

OMC Sterndrives - OMC Outdrives - Cobra Sterndrives - Crowley Marine

According to that link putting a hydromechanical foot where a mechanical one went involves using the mechanical shift cable and making a change in the shift cap.

If the '86 is indeed a stringer drive then read my post above. All that would apply. You do not need to 'modify' anything. You just need the proper 'shift converter' box and the proper 'shift cable' that are designed for the hydro-mechanical lower drive. I do not think that you can change a mechanical drive shift converter box to work with the hydro-mechanical drive. Apparently, they shift in opposite directions.
 
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