Picked up an '84 115 hp parts engine today to compliment the '86 125

home-boy

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The 115 looks pretty decent but hasn't been run in years and after I pay and get it loaded I learn it has shifting issues, helicoiled spark plug hole and a chip out of the top of the flywheel. Things the seller held back until the money hit his pocket.

It came with controls (cut cables) and a tilt-trim button on the throttle which I need as well as a SS 21 pitch prop so I guess it was worth the $150 it cost me.

Is it identical to the 125? Looks like bore, stroke, pistons, ignition and everything else is exactly the same.

I guess I'll sell the old 120 that is now missing the lid

:)
 

jerryjerry05

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Do a compression/spark test before you change it.
The prop was worth the 150!!!
 

home-boy

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I did not plan on using the 115, I already have the 125 installed and it starts like pulling the trigger on a gun.

I bought this additional 115 for the prop, lower unit (spare) ignition system, tilt assy with controls, and the better hood that is not all busted up

Are the internals the same on the 115 and 125?
 

Frank Acampora

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The 115 has a 2.80 stroke crankshaft. The 125 has a 2.875 stroke. However, the pistons are the same diameter--3.312 if it is indeed a 1984 engine. Earlier 115s had a 3.375 piston. Connecting rods are the same for ALL Chrysler and Force from 20 horsepower on up until about 1994 when Mercury increased the length and bearing diameter.

I have a125 block into which, as an experiment, I fitted a 2.80 crank. It may not be producing 125 horsepower but it is not far from it. It runs 45 on my 15 foot Glastron.. You can see a video of it if you go to youyube, Frank Acampora videos.

\ Carbs nay be different-- simply check the numbers-- but if they are the TC carbs they will swap onto the 125. Flywheel is the same but don't even think about using a chipped flywheel, not even in an "emergency." simply throw it out Electronic ignition is basically the same and relatively easy to swap.

Lower unit and the midleg is the same as are the power tilt/trim (if it has one) and all other associated hardware. The shift problems are easily repaired if it is not popping out of gear due to worn dog clutch
 

home-boy

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My '86 125 seems to run good. I have not done a compression check yet but it fires so quickly after bumping the key I know it is a good engine.

I will move the prop and the hood immediately and save the rest of it (except the tilt, I think I have it sold)

Wiseco shows the same part # on both the 115 and the 125 pistons so I thought they were the same. It seems like it was a good buy for me.

Anyone want a great running 1972 120?
 
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