120 would swap in no problem. The 165 is most likely the inline 6 which would take some mounting work or the 3.7l which would also take some mounting work. Either way with a 165 you would need to change drive ratio or try to compensate with a prop.
120 would drop straight in, but that is not the way you really want to go. With a new front engine mount structure on the bottom of the boat, a 165 would also drop straight in, but you would need to change the gear ratio in the upper drive.
Yea i called a machine shop today they qouted between 1500 and 2000
Still set on doing it myself accept the machining need a shop manual for this engine from there i will make decision to move forward or pay to have it done thanks for advice
having done my share of rebuilds, you will save about 3 hours of labor doing it yourself assuming you have the proper tools.
for the price of a rebuild, you could get a complete and running engine for much less, strip it down to the long block and swap it in place. then again for $2k you could buy a complete running boat.
You'd be going from 140 horsepower to 120 horsepower, and a similar drop in torque. The performance difference would be very noticeable. I have done quite a few re-powers going the other way, and people always say the same thing, "Why didn't I do this years ago"....
the other reason is that the 120hp (2.5 liter or 153 cubic inch) engine has not been in production for over 20 years, where a 3.0 / 140hp is still in production and can be found everywhere.
