Force 120 compatability

[rhedayi]

Gang. I have a trophy with a force 120. It’s got a 25 inch shaft. I may want to pick up a spare but i honestly don’t know if the engines are similar enough to be compatible like lower units, the engine block etc. I’m fairly certain the motor i found is 20 inch shaft. My engine

 

[rhedayi]

The spare unit

 

[rhedayi]

If the engine was to lose compression or have other failure could the lower unit with the extension kit be a direct swap over onto the spare motor?

 

[jerryjerry05]

What's the years on the motors??
Looks like they are both close as both use mainly Mercury equipment(pack/coils etc.)
The lower units are different in the shaft they use. 5" difference.
If you post the year of the 2nd motor I can compare the parts and see if the shafts can interchange.

 

[rhedayi]

I will try to find this info

 

[rhedayi]

What's the years on the motors??
Looks like they are both close as both use mainly Mercury equipment(pack/coils etc.)
The lower units are different in the shaft they use. 5" difference.
If you post the year of the 2nd motor I can compare the parts and see if the shafts can interchange.

Jerry i went to check out the motor. The boat is a capri with the last 4 of the hull id c595. I think that’s a 95 and assume motor is same year. The lower unit looks the same except mine has the extension bee between it and the head. The motor under the cowl looks identical except the ignition. Thank you for your help

 

[jerryjerry05]

The drive came in 20 and 25 "
The older models came in a 2 piece configuration. The shaft on these is a one piece.
The parts can interchange if you have the service manual and some tools.

 

[rhedayi]

Jerry. Do you think rather than messing with the shafts the entire lower unit can be swapped over from one to other? That way you just bolt the extension and lower unit with the longer shift shaft and driveshaft. Thank you

 

[jerryjerry05]

Yes that might be possible.
I've not done it myself.
The things like the water pickup would need to be fit.

 

[rhedayi]

Yes that might be possible.
I've not done it myself.
The things like the water pickup would need to be fit.

I appreciate the insight. Thank you so much

 

[jerryjerry05]

Good luck, keep us posted.