Opinions on 1975 Evinrude 115

[imbatman]

How are these motors? Im looking at what is supposed to be a really good running one with controls and all for $500 bucks. Its older than I want but that really doesn't bother me to much if its a decent motor. Im going to see it this weekend and will do a compression test.

Questions:
-Are these the "red" plug for the motor wiring harness?

-Are any of the parts compatible with a 96 90hp Johnson
-----Lower Unit?
-----Engine mount/Tilt trim... The 1975 does not have tilt and trim but my blown '96 90hp does.

Can you still get parts like carb kits and coils?

[jeff_3272]

Just walk away. "Supposed to be" and a 45 year old outboard never go good together.

[omcforever]

Are any of the parts compatible with a 96 90hp Johnson NOPE
-----Lower Unit? NOPE
-----Engine mount/Tilt trim... The 1975 does not have tilt and trim but my blown '96 90hp does. NOPE

Can you still get parts like carb kits and coils? YEP but why?????

[tdt91]

Don't waste your time or money on that old turd. Save up and get something in the 90s at bare min

[imbatman]

Thanks all

Don't waste your time or money on that old turd. Save up and get something in the 90s at bare min

Actually found a 96 120hp that I am going to check out. Cross-flow or Looper? I can't find consistent info to tell without lifting the cover and don't know my OMCs well.

96 120.PNG

[omcforever]

Need a model number. Don't think they made a 120 Johnson in 1996........

[omcforever]

And a 120 is a looper. V4 looper has 4 carbs,,,,,,,V4 crossflow has 2 carbs..

[imbatman]

Thanks OMCforever. Its my understanding the crossflows are lighter but the looper is stronger but both good motors....?

The 1996 was in the ad I have not seen the motor in person yet. This week though.

[imbatman]

Need a model number. Don't think they made a 120 Johnson in 1996........

Good call.. I looked up 120hp by year @ Crowleys Marine parts catalog. The last 120 they made in the 90's was a 1994. Should help negotiation a little.

This one is at a dealership and was "just serviced". I am going to do a compression test and hear it run in a tank where we can out it under somewhat of a load. Asking price for it is $1,200.

ALSO
My 90 is actually a 1995 (J90MLEOR) so its a crossflow? Any swap over in parts? I assume the looper is a red plug...?

[tdt91]

A dealership is advertising a 1996 120 when there is no such thing? Not sure I would trust them much.

[omcforever]

My 115 is actually a 1995 (J90MLEOR) so its a crossflow? Any swap over in parts?

Nope,,,,well maybe the lower and the prop....2 differents beasts.

[imbatman]

A dealership is advertising a 1996 120 when there is no such thing? Not sure I would trust them much.

LOL yeah, but knowing some sales folks they will look at the year of the boat and assume the motor is the same.

[imbatman]

It is worth rebuilding my old 90? It would have to have one sleeve put in. I got it already blown but it looks like maybe the wrist-pin retaining clip failed and it gouged the cylinder wall deeper than a bore and slightly bigger piston would be able to fix.

Piston fail1.png

I got a very rough estimate for a rebuild of 1800-2300.

[omcforever]

Have you actually checked the bore diameter and runout and depth of gouge? Crossflows are $$$$$ to sleeve right. Sleeves are cast in during forming of block. Cant just heat em, slide em in and out easy like other motors. Easier to find a donor block and go that route or find a newer, used Looper for your boat.

[imbatman]

Have you actually checked the bore diameter and runout and depth of gouge? Crossflows are $$$$$ to sleeve right. Sleeves are cast in during forming of block. Cant just heat em, slide em in and out easy like other motors. Easier to find a donor block and go that route or find a newer, used Looper for your boat.

How much can they be bored? Here is a better pic of the damage to the cylinder wall with the head removed. Its deep like a couple of mm's maybe.

I really do appreciate the info!!

Piston fail 2.png

I never cranked it up when I got it but I was told it would still run but sound like hell...

[omcforever]

Have no idea what we are looking at. Take another picture of the hole cylinder. Crossflow can be bored up to .040 over reliably. They make bigger pistons but anything over .040 and you run into thin cylinders/distortion under heat and stress, and other not so nice things. Need to invest in a real OMC manual and get some readings on the cylinders. The manual explains this process. Until then, everything is a guess.

[omcforever]

Here is a starting point,,,crossflow cylinders are 3.50 diameter stock. There is a detailed process in the manual on where and how to take the measurements.

[omcforever]

Chapter 4 in the OMC service manual shows the process. I cannot get a clear image of the process to take/post,,,,invest in a manual if you are serious..

[imbatman]

Have no idea what we are looking at. Take another picture of the hole cylinder. Crossflow can be bored up to .040 over reliably. They make bigger pistons but anything over .040 and you run into thin cylinders/distortion under heat and stress, and other not so nice things. Need to invest in a real OMC manual and get some readings on the cylinders. The manual explains this process. Until then, everything is a guess.

Its a pic of the scored piston wall from the wrist pin issue.

"40 over" is just over 1 mm (I gotta go to metric as a Japanese truck shade tree mech). The gouge is deeper than that without any doubt at all. Ill measure just to find out how much though. The mech that looked at it when Collins Boating was considering trading for it said there was no doubt it would have to be sleeved.

[ChampioNman]

To add, you can go up to .030 with OEM pistons but you can go to .040 with aftermarket pistons, only caveat with that is if you decide to go with aftermarket then replace the remaining pistons with the same manufacturer. Don't mix and match manufacturers due to weight differences.