!985 Evinrude 120 heads

[SS Minnow]

Are these the heads I would want to get for a 1990 140 to raise the compression? Or are they too old?
Thank you.

[racer]

Yes they will raise your compression. However they have a very similar chamber to what you have unlike the V6 when bore increased. You can cut yours down and get the same results. IMO if your boat is set up right and not heavy you can cut them to 46CC.

[SS Minnow]

Thanks for the reply. I guess I should explain a little more of what I am trying to do.
I have a 1990 Evinrude 140 on a 1979 Checkmate Trimate II. It may be a Trimate III, it is the 16 foot for sure, so whatever that one is.
Boat moves real good as is. No complaints with a variety of props, but use a 17" SST (ss 3 blade) for skiing and a 24" Raker for distance.

I have been reading about these motors and there is a 120 near me that is being parted out. I thought that if these were the right heads, I could buy them for a project later down the road.
I have a stock motor that is 28 years old. It runs good now, but I understand it could use a looking at. So while I am in there I could put the hi comp heads on with updated reeds. Remove the airbox, re-jet the carbs and see what happens. Also install some solid mounts while I am in there. I know there are more things to do, but thats why I would like to gather some parts and go from there.

The boat that the motor is on is in good shape, but I can see it not being around for much longer. It is a good for ow with kids being the age they are, but not for much longer. At that point I would put the motor onto something designed for more speed.

Thanks again for the help.

[powerabout]

use a 140 inlet and reeds, there's 20 hp

[SS Minnow]

I am confused, i think. I currently have a 140. Model year 1990.

I have a donor motor nearby, a 1985 120.

[racer]

If you have a 1990 140 you have the good carbs and your intake already has the 6 pedal reeds. The 120 along with the 1985 140 had 5 pedal reeds all 140 after 85 had the 6 pedal.

[SS Minnow]

So, i should not take any parts from the 1985 motor?
i am confused.

[powerabout]

just the heads but if you machine yours they will be the same
( sorry I miss read you already had a 140)

[MattGreen]

Those are great engines. If I was you I would grab that 120, many of the parts are useful for your motor although as mentioned not for performance gains. Is the crank good on the parts motor ?

Matt

[SS Minnow]

Thanks for the replies all.
i would rather use the older heads on my motor compared to machining what i have. I am not a machinist and do not have a good one near me. It is way cheaper and a safer bet for me to try the second set of heads for so many reasons.

As far as ofter parts of the motor and what is good, i do not know.
https://madison.craigslist.org/bpo/d...555556062.html

That is the ad i found. For all i know the heads might not be any good, let alone the crank.

i am just starting to collect some parts to build the 140. I would not start working on the motor until this winter at the earliest. Figure on putting the smaller heads on, remove my airbox, replace reeds with new, solid motor mounts. Nothing serious, but a little project to use more gas.

Thanks all for the help.