# Mercury 20 to 25 conversion



## Morgan_Duett (Jan 12, 2013)

Anybody put a 25hp carb on a 20hp motor? Is that all you have to do or is there something else involved? 2 stroke motors by the way.


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## jonrconner (May 20, 2015)

I may be wrong, but I think the 20 and 25 are not the same motor, the 25 is the same as a 30 and CAN be upgraded from what I have heard.
JC


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## RunningOnEmpty (Jun 20, 2015)

The 20 and 25 use the same block. The 25 carb bolts right up if you get the proper year carb.


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## WeeHooker (Aug 26, 2016)

It would depend on the vintage and design of the motor. The new four strokes are completely different inside. That said,I know the later 2 strokes 20 and 25 were built on the same block. That is usually an indicator that the upgrade is simple. FWIW, I've done several Carb only swaps on various small two strokes in he past that worked just fine.
PM me if I can be of help.


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