1984 Johnson 115 Spark issues

[Scovbert]

I didn’t try it yet, should I use water? I know it’s not great for the impeller to run dry but it might be the only way to tell if water is getting in there.

 

[Bosunsmate]

Yes use water. If it doesnt light when soaking wet then drop the LU that way you can run it without water.
Any other way risks burning up your impellor and sending bits up into the motor which will add a lot to your frustration.
On a new to you motor you should change the impellor anyway so itd be good to drop it anyway, even if just to familiarise yourself with it

 

[Scovbert]

Had a good friend come by today who’s a good outboard mechanic. After doing several checks, doing a drop down test it’s confirmed a 100% that the two lower 2 cylinders are not firing as I’ve suspected. We also determined that the liquid is fuel, not water. I can’t tell you exactly what he did to determine that, but he was very confident. Upon his inspection he believes it’s a fuel issue and that the cylinders are not getting enough fuel. He recommended looking at the lower carb and the reeds. I’m also not saying he’s necessarily right but i know he knows a lot more about this stuff than me.

 

[Scovbert]

Removed the carbs and cleaned the lower one. While off I inspected the reeds and so no signs of damage or being bent and held open. Put everything back together and tried again, didn’t seem to help. Also, back to this steam I keep seeing. It is still coming from the exhaust and it follows the cylinders, meaning after it’s hot and I take all the plugs out as I turn the flywheel the steam goes where the exhaust port are open. Not sure if this matters and seems to make sense logically. I’m just not to sure if there should be steam/smoke anywhere?

 

[Bosunsmate]

There shouldnt be steam anywhere. I suggest dropping the LU and running it then that way you can confirm if its got water in it which makes steam or not
Its a relatively easy job to drop, just make sure to undo the shift shaft screw, its normally under the bottom carb or nearby

 

[Scovbert]

Unfortunately it’s not that simple because it’s a sea drive and the entire lower unit is attached to a bracket mounted on the transom. I’d have to pull the power head.

 

[racerone]

Why then does this topic start out with 1984 Johnson 115 HP.?------It is simple.-----Remove the lower unit just like on an outboard motor.-----And no you do not have to pull the powerhead to remove the gearcase !!

 

[Scovbert]

You’re right, thought you meant the mid section as well...I follow you now! Thank you.

 

[Scovbert]

Dropped the lower unit. I found something and I’m not sure how big of a deal it is. The top of shaft has a spline with what looks to be a groove for an o-ring. That o-ring was not in the groove and I found it located about half way down the shaft. Also I ran the motor for about 15 seconds and then I pulled plug number 3 and steam still came out. Is it possible that water was still in there from earlier today? Thanks again for helping me out, I’m doing my best.

 

[Bosunsmate]

ahh progress, good.
Run it again to be sure to dry it out as yes water will still be in there from this morning. Just run it until it gets hot under your hand, but no where near too hot to leave your hand on it. It should start very easy without an LU and be a wondrous sound for ya.
And that oring helps seal the lower crank from water intrusion. It could affect the very bottom cylinder but im unsure at present how itd affect the next one up.
Keep up the testing-need to get to the root cause of this steam

 

[Scovbert]

My top two cylinders fire just fine, it’s the bottoms that don’t, so that makes sense. I’ll run it again and try to get whatever water is in there out. Then report back. Is it possible this o-ring is my problem?

 

[Scovbert]

Ran it for about 30-45 seconds until hot but not over heated. I pulled the plug and steam is still present. I didn’t want to keep running it till it cooled down.

 

[Bosunsmate]

My top two cylinders fire just fine, it’s the bottoms that don’t, so that makes sense. I’ll run it again and try to get whatever water is in there out. Then report back. Is it possible this o-ring is my problem?

Yes itd affect the very bottom cylinder but the one above it is in a separate chamber and i doubt water could get up that high. You would of noticed a lot of water in your carburettor. If your lower bearing has a scavenge tube to the carb that powers the second to bottom cylinder then i suppose its possible
O ring would add to the issue if it is where waters getting in. There is a main seal that keeps water out but if both are ruined then water will get in

 

[Bosunsmate]

Ran it for about 30-45 seconds until hot but not over heated. I pulled the plug and steam is still present. I didn’t want to keep running it till it cooled down.

Pulled plug or plugs? You could post a video showing this. Post a youtube link if it doesnt post a video on here

 

[Scovbert]

So what’s the next step? Should I replace the o-ring and put it back together and test? or should I check the seal your talking about before moving forward? Thanks for the insight!

 

[Scovbert]

Pulled plug or plugs? You could post a video showing this. Post a youtube link if it doesnt post a video on here

I only pulled one plug at that time. I can rerun tomorrow and then pull all 4 plugs. I didn't bother to pull the top two plugs because they fire as they should. Tomorrow I’ll run this test and report back. I’ll also try to make a video.

 

[Bosunsmate]

I only pulled one plug at that time. I can rerun tomorrow and then pull all 4 plugs. I didn't bother to pull the top two plugs because they fire as they should. Tomorrow I’ll run this test and report back. I’ll also try to make a video.

just bottom two will do.

 

[Bosunsmate]

So what’s the next step? Should I replace the o-ring and put it back together and test? or should I check the seal your talking about before moving forward? Thanks for the insight!

Keep the LU off until this steam issue is known to be caused by water from LU or not.
That seal im mentioning for replacement means pulling the powerhead so need to be more certain its that before embarking on that cheers

 

[Scovbert]

Lower cylinder #3

 

[Scovbert]

The picture on the bottom is cylinder #4