Problem with Johnson outboard
Submitted by harich4 on Wed, 2015-12-16 07:32
I have a 115hp Johnson outboard 2 stroke that's has a problem.
The last few days I've started to have problems with my motor. been going out to check my pots and I can only cruise out at 8 knots any faster and the motor starts missing and struggling. Once I've pulled my pots I head back doing 25-30knots nothing is wrong with it.
Does anyone wants wrong with it?
cheers
NORUN NOFUN
Posts: 1019
Date Joined: 15/08/11
Mobile mechanic
Normally always fuel or spark, but do yourself a favour and hit up a marine mechanic - getting stuck in the middle of nowhere is not good.
harich4
Posts: 15
Date Joined: 17/03/11
I've changed the spark
I've changed the spark plug.
ive replaced the whole fuel line and ran it off a 25ltr plastic tank.
You reckon it could be the leads to the spark plugs?
Grey Ghost
Posts: 183
Date Joined: 12/10/15
Arcing
You are not getting arcing between a slit split/cut in spark plug lead and the engine cover? I have a 140HP Evinrude that used to do that all the time.
"Grey Ghost", 670HT Barcrusher with 150 Yamaha, based at Cockburn PBC.
Grey Ghost
Posts: 183
Date Joined: 12/10/15
Arcing
You are not getting arcing between a slit split/cut in spark plug lead and the engine cover? I have a 140HP Evinrude that used to do that all the time.
"Grey Ghost", 670HT Barcrusher with 150 Yamaha, based at Cockburn PBC.
sandbar
Posts: 704
Date Joined: 25/10/09
How far oout
how long travelling time till you get to the pots? Does it miss and fart out out of the water with the muffs on, what colour is the smoke? Does it have auto choke?
harich4
Posts: 15
Date Joined: 17/03/11
5-6ks doesnt miss with the
5-6ks
doesnt miss with the muffs on.
cant tell you what colour the smoke is because I'm colour blind haha
and it doesn't have auto choke
OOH YEH
Posts: 384
Date Joined: 16/06/15
Fuel / oil mix
It sounds like a bad mix of fuel to oil ratio ??????
harich4
Posts: 15
Date Joined: 17/03/11
we have tried the oil.It was
we have tried the oil.
It was pumped automatically but I've disconnected it and mixed 50-1.
could it be wrong oil for the motor? Have Yamaha oil from boat city Balcatta
or does it have the wrong spark plugs?
NORUN NOFUN
Posts: 1019
Date Joined: 15/08/11
If your mechanically minded
I used to have an old johnnie 2 banger on my tinnie.
When I first took it for a spin it would run fine at idle, but as soon as I tried to take off it would not get up on the plane, really labouring.
Changed out all the fuel, filters and cleaned the underfloor tank out, took it for another run and would still do it.
Ended up taking the fuel bowl off the carby and found that the fuel in the bowl was like a green jelly, cleaned all the crap out from there and she ran perfectly.
harich4
Posts: 15
Date Joined: 17/03/11
Cheers everyone I'll try it
Cheers everyone I'll try it all out tonight
Sulo
Posts: 256
Date Joined: 13/08/11
My 115 was missing and
My 115 was missing and coughing and farting, sometimes was worse than others and pretty random at best, usually at mid to wide open throttle. After a lot of searching found it was the ignition control box, the old sealed black box of mystery. Yours is down low so may not be the issue. Check everything else first and then maybe get a marine mechanic to investigat the ignition module if nothing else works. Apparently a common issue and they just go from time to time.
Brock O
Posts: 3163
Date Joined: 11/01/08
Ive had similar
issues with my 115 Johnson, if its a spark issue you should see a difference in the plugs.
We changed all plugs as they were due before checking spark through all leads, can pull leads one at time why motor is running, or use a multi meter...repco or supa cheap. from this can give an indication...make sure you have no fuel around if pulling leads while running..
After this we did an Ohms check through each of the coils, one was on its way out.....working on and off.
$67 from Chivers and running sweat again, a good factory manual gives details on all these checks, mines a 1995 model which we rebuilt so we bought the manual for this.
Mattyb84
Posts: 388
Date Joined: 28/12/12
+ 1 for the Carrbie bulbs
+ 1 for the Carrbie bulbs had a 90hp vro with the same drama clean the bulbs problem solved
Pgfc member
West coast pom
Posts: 38
Date Joined: 17/03/11
I had the same motor (johnno
I had the same motor (johnno 115 2 stroke) and it did that a couple of years ago. I did everything- plugs, leads, carbs, VRO pump, even pulled the floor hatch up and replaced the entire fuel system...kept doing it but not regularly enough to be able to really work out wtf was happening....in the end it was the power pack. Got one from the U.S. online ($200 if memory is right). 15 mins, 4 bolts and hasn't missed a beat since!!
best of luck mate, I know exactly how frustrating it is!
crasny1
Posts: 6986
Date Joined: 16/10/08
Identical story
Had a 115 2s Johno out of dampier scare the shit out of me. Fine on the way out 20nm. Bottom bash anchored up for 5 hrs. Then ran like a dog. Darren from Cobra Marine is a mate so called him, and it was the Power Pack, black Box whatever it is called. Pinched an old one off a old motor and good to go.
But replaced it with a Evin ETEC 115 and NEVER looked back.
"I would like to die on Mars. Just not on impact!!" _ Elon Musk
sunshine
Posts: 2555
Date Joined: 03/03/09
Isn't spark governed by a magnet
on the underside of the flywheel - was on my old 200 Jonno, bloody thing came loose and gave all sorts of intermittent problems - Chivers tried everything before they finally pinpointed the issue - gladly replaced with a 225 four banger yammy