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1981 Evinrude 115 rough at low speed

James ion Canada

James ion Canada

Member
Greeting everyone.

I have a new-to-me E115TLCIM that seems a little rough in the mid-range and idle.
Once the boat is up on plane the engine seems to sing just fine.
I have some experience with automotive engines but this is my first two stroke
marine engine.

I have a sixty second video of starting and idle posted here: https://youtu.be/zATUcmqnbcU

Maybe you will tell me it is running acceptably and maybe you will see a problem.

I will try and answer any questions to the best of my tools and ability.
Thanks in advance!
James
 
All four spark plugs present as wet fouling.

The plugs were cleaned recently and gaped to .030.
 

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Where in Canada ??----Are the thermostats installed and working properly ??------Do you have spark on all 4 that jumps a gap of 7/16" or more ?-----Plug look ok to me.
 
racerone said:
Where in Canada ??----Are the thermostats installed and working properly ??------Do you have spark on all 4 that jumps a gap of 7/16" or more ?-----Plug look ok to me.
Click to expand...

Lake Simcoe (Ontario). I can't say if the thermostats are stuck open but there is no sign of overheating. I can measure the head temps with an IR thermometer next time I am out unless running it in a barrel is good enough. I'm making a spark tester and should have a video for tomorrow.
 
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Along with the video, make a blunt statement of the spark... that is whether it actually jumps the 7/16" gap with a strong blue lightning like flame... a real SNAP!... or not! A weak spark will result in spark plugs like that graphic shown.

Observe the stator under the flywheel closely to see if there might be a sticky looking substance dripping out of it, down on the powerhead area. If so, replace it as that would cause a AC voltage drop to the powerpack's capacitor which would in turn result in weak, erratic, and eventually no ignition/spark.
 
joereeves said:
Observe the stator under the flywheel closely to see if there might be a sticky looking substance dripping out of it, down on the powerhead area. If so, replace it as that would cause a AC voltage drop to the powerpack's capacitor which would in turn result in weak, erratic, and eventually no ignition/spark.
Click to expand...

I will try and have a look at that tomorrow.
 
joereeves said:
Observe the stator under the flywheel closely to see if there might be a sticky looking substance dripping out of it, down on the powerhead area. If so, replace it as that would cause a AC voltage drop to the powerpack's capacitor which would in turn result in weak, erratic, and eventually no ignition/spark.
Click to expand...

Is this what you are talking about?

Goo 01.jpgGoo 02.jpg
 
Well, that certainly looks like a sticky looking substance... NOW, how about telling us verbally and with a graphically view of the stator (excellent pic taking by the way) as to where that goop is coming from. Actually there's only one item whereas that could originate (stator) but we'd like to see it anyway. That's the worse meltdown scenario I've ever seen!

To answer your question... Yeah, that's what I'm talking about.
 
I don't have a flywheel puller yet so I can't do a overhead shot but the goo on the right side (top photo) is where the timer base connects to the throttle linkage.
On the left side (bottom photo) it is just aft, about two inches, of where the wiring harness goes into the stator ring.
 
James.... The view I would be interested in would be the bottom extreme forward & rear portion of the stator. That's the location of the sealed in larger coils (1 in each location) that supply the AC voltage to the powerpack capacitor. And as such, that's the specific area whereas one could see the leakage point. No need to pull the flywheel to view that area.
 
I had a look and didn't see anything at the front or rear. just on the left and right sides.
The motor did have a blown charging system. I replaced the rectifier and regulator with a RMStator integrated
rectifier/regulator and it is now charging.
 
James ion Canada said:
I had a look and didn't see anything at the front or rear. just on the left and right sides. The motor did have a blown charging system. I replaced the rectifier and regulator with a RMStator integrated rectifier/regulator and it is now charging.
Click to expand...

The sides.... That would normally be where the battery charging coils are located, and I've never seen any of them melt down... just the large ones fore and aft that provide power to the powerpack capacitor. Makes me wonder if that stator is installed sideways, if that's possible... never tried that.
 
I did the spark test and got a strong, blue spark on all cylinders.
Video to follow.

When I first got the boat, I was checking over the motor and I noticed that I heard an electrical
arcing sound when I turned the the flywheel. On investigation I found one of the wiring harnesses
under the flywheel was loose and rubbing on the flywheel. It rubbed through the main power (red)
and tach signal (grey) wires. I repaired and re-routed the harness. I'm pretty sure that's what did in
the charging system and probably the source of the brown goo.
 
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If the stator is indeed leaking, dripping down a sticky looking substance on the timer base and the power head area (a situation you will need to determine)... the stator will require replacing regardless of what readings you obtain from it.
 
joereeves said:
If the stator is indeed leaking, dripping down a sticky looking substance on the timer base and the power head area (a situation you will need to determine)... the stator will require replacing regardless of what readings you obtain from it.
Click to expand...

I have a puller on order. Will post details about the stator probably next week.
 
Those two large coils are what normally melts down. They supply AC voltage to the powerpack.

The meltdown on that stator shows a leakage of the battery charging coils. That type stator basically has existed since 1973 and I have never seen a meltdown like that (Battery charging coils).
 
joereeves said:
Those two large coils are what normally melts down. They supply AC voltage to the powerpack.

The meltdown on that stator shows a leakage of the battery charging coils. That type stator basically has existed since 1973 and I have never seen a meltdown like that (Battery charging coils).
Click to expand...

See my explanation for this in post #16.
That's probably it for this engine for this season.
Other places for the time and money to go.

Ill check back in when I get a replacement stator.

Thanks everyone!
 
James ion Canada said:
See my explanation for this in post #16... That's probably it for this engine for this season... Other places for the time and money to go... Ill check back in when I get a replacement stator... Thanks everyone!
Click to expand...

Understood. Just double check the wires leading to the stator (before you install the new one) to make sure that there is no DC battery voltage being somehow applied. Yeah, your post #16 pretty much spells it out but it's best to double check the voltage mention.
 
Ok, so I got a new CDI stator and put it in today.
I took the opportunity to do a little before and after testing.
These are all voltages taken with a DVA and Digital Meter with
the engine running at about 1000 rpm.

Some Before figures:
Alternator output 14.5 volts (not really meaningful...changes with electrical load)
Charge coil output odd: 300 volts.
Charge coil output even 280 volts.

After replacement:
Alternator output 15 volts (Less load from battery)
Charge coil output odd 305 volts.
Charge coil output even 280 volts.

No change in engine performance.
The engine has no trouble starting, just stumbles a lot
below about 2500 RPM. Once on plane the engine seems
to run just fine.
 
Oh, I almost forgot...

Once warmed up, the cylinder temps seem to top out
around 120 Degrees Fahrenheit as measured about one
inch left of the spark plugs. The #2 cylinder was about
3 degrees cooler though.

The engine is running in a barrel and not on muffs.
 
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