johnson 115 troubleshooting

[thedeuceman]

so im tryn to get get this 115 on the V173 i acquired running, when i got it the lower unit was broken from hitting a rock (i am told)
tried to get it started right away, just backfiring, turned out to be a sheared key in the flywheel, fixed that.
checked comp, 125-130 in all 4. installed new NGK plugs. PO installed new CDI module
also had gas all over so i pulled the carbs apart and found a torn up needle valve, cleaned carb body's in cleaner (found out later i was not spose to do that) and put them on. i can get it started but seems rich/flooding out, took them off and checked everything again.
also connected directly to tank and pumped primer bulb and they did not over flow (should mean floats and needle valves are ok)
so it runs at high rpm but will not idle, when it kills the lower carb is wet, but it seems odd that i have to choke it to get it started again.
here are some videos, the second one it dose not sound to me like its missing, but it does in the others.
and yes in the third video i forgot to turn the water on :-( but it does still pump.

IMG 1586
IMG 1588
IMG 1589

thanks guys !

[Rich_V174SS]

Sounds to me like it's not running on all cylinders. Check for spark at each plug.

[thedeuceman]

yes, all 4 plugs have spark

[Jerry]

my guess is you may have a vacuum leak. or bad reed valves.

[Retro Performance]

It does not seem to be smoking much......What is fuel/oil ratio?.....Usually smoke if they are rich.......I wonder if carb cleaner were sprayed into the air box while running if it would pick up(if lean) or bog down (if rich or correct)........Pre VRO? might check for ruptured fuel pump diaphragm?

[thedeuceman]

its pre VRO, inspected the pump, then swapped it out with another.
fresh gas 50:1
i will try checking for vac leaks with carb cleaner tonight

[thedeuceman]

so i checked for leaks, pulled the intake off and checked the reeds... all ok
noticed some gooey stuff on top of the motor, it had come from the exciter coils so i checked them, they read 700 ohms spose to be 400 to 600. so i swapped the stator, seemed to run better but still wont idle (im sure the floats sinking, got kits now)
swapped  the coils and CDI, still the same. pulled the plugs to try to read them and on #1 the gap seems too small (i thought i noticed that when i pulled the originals out) im thinking this is bad, like a bad wrist pin or crank bearing :-(
NGK B7HS10 plugs. so check distance from plug land to piston at TDC of each cyl with depth guage on a caliper.
2 and 4 are right at 0.6", 1 and 3 are at 0.594 but i cant find a spec for that anywhare.
the junk 85 i have is 0.7"
right now i have 2 seals on each plug for testing the motor, if the bearings were that loose i would expect to hear it knocking.
i did read 1 post somewhere about this problem, sounds like the guy ended up running 2 seals on his plugs.
anyone seen this before ?

[MarkS]

You can do a "slap test" for worn wrist pin bushings/bearings Joe. 

1 - Turn the motor over by hand until the piston is on the down stroke.  (The connecting rod will be pulling the piston down at this point.)
2 - Take a dowel rod or screwdriver and insert through the spark plug hole, push down on the piston.  If you feel any movement, or hear a "clunk" (noise of any kind, really), more investigation (tear-down) is needed.

I've got the same plugs you're running in my 115 E'rude right now, but normally run the surface gap style. 
http://www.maxrules.com/OMCplugchart.html
If the piston is contacting the plug you should hear that, and see evidence on the electrode of the plug (and top of the piston) I would think......?

[Hyperacme]

Did I send you a repair manual link ?

[thedeuceman]

Yes, thanks for that
There does not seem to be a spec for that meaurment, or at least that i can find, but they have helped me get this far.
And i did try the test mark discribed, i felt no play.

[V153]

Have you rebuilt/replaced the fuel pump?

[Quesa]

Same problem here with our johnson 115 on a 76 baja, It runs and sounds just like that-with it cutting out.  Its a pain to get started, as long as I keep it above idle I can keep it running. Runs great at half and full throttle. It does not like 'no wake zones', after 5 min. it starts to cut out just like the video. Backing off the the boat lift most of the time i can not get from reverse to forward with out it dying. Is it not getting enough fuel when cold and/or too much when hot? Has nothing to do with fuel?  Its been in the shop to many times over the last ten years for this problem. It has never come home corrected. I can go on and on,I better stop, I'll hang up now and listen to your response.

[thedeuceman]

After that video i replaced the stator because the exciter coils read 700 ohms, that seemd to make a difference.
I pulled it off the v173 because i am selling it, and i have a 66 80 hp on my stand im trying to sell so i wont be working on it for a while, need to get the GT togeather
I will post status when i resume

[Hyperacme]

When I got my Johnson from Pete, he told me to replace the thermostat every year with a OMC/BRP stainless steal one.
Thought that was kind of weird ...
Ran great all year, but the next season it didn't want to idle for more then 30 seconds ...
Replaced thermostat and it ran great !
Rich said it was the motor was not getting up to temp. and wouldn't idle.

Don't know if it will help your problems ...

[Quesa]

I will try that this week, Thanks!

[Hyperacme]

Check your PM ...

[Retro Performance]

We have had some success over the years rejetting larger on the idle circuit on OMC product........fixed jets and sometimes need to go bigger.........if you test everything else ok you might try this. Keep in mind todays fuel is not the same as it was when this motor was built, sometimes motors need to be adjusted or "adapted" to run. By the way was someone right behind a Crestliner with a real nice GT 160 ? last friday morning going north on 169? I was hauling a boat up and saw a really nice Glastron heading up(I think maybe a GT160).........If it was someone from here I had the Purple Vee Bottom with the Evinrude Hustler on it and your boat looks great.