1984 Johnson 115 Spark issues

[Scovbert]

Where is your shop? Spark is good on all 4.

 

[racerone]

About 800 miles away.------I will repeat the question once more.-------Does spark jump a gap of 7/16" on all 4 leads , yes or no ?-----

 

[Bosunsmate]

Id change the headgaskets, they are much easier than the exhaust one. May as well do both if you arent sure about the other cylinder being totally operational too. Dumpster is out of the question, or a long way from considering that at least.

Plane the heads when they are off, its crucial. Put some light sandpaper on a mirror or piece of glass and move the head in a figure 8 pattern until the whole face is shiny (that means no low patches are left).
Its worth checking the crankcase faces with a straight edge while you have the heads off, but its rarely the issue. The heads have warped a bit almost the whole time ive checked them

 

[Scovbert]

Ordering the gaskets now and I’ll start disassembling the heads tonight. Thanks for the heads up on the plaining, I’ll be sure to do that. Keep you posted as I go.

 

[Scovbert]

Ordering the gaskets now and I’ll start disassembling the heads tonight. Thanks for the heads up on the plaining, I’ll be sure to do that. Keep you posted as I go.

 

[Scovbert]

Racerone, more specifically yes it easily jumps a gap of 7/16” on all 4 cylinders.

 

[Scovbert]

I took off the starboard side head tonight and the gasket looked pretty good. Doesn’t mean it wasn’t leaking but I don’t see anything that was obviously leaking. The pistons are dated to 2012 so that’s the last time this was rebuilt. I’m going to replace the head gaskets just to say I covered my bases. If this doesn’t resolve the issue where else could this thing possibly be getting water in the lower cylinders from? Thanks as always.

 

[Bosunsmate]

Have a look on the cylinder walls for little cracks, Rotate the piston back so you can see as much of the bore as possible.
Dont get to glum yet, it may of being that the person who installed the thermostat unit with no thermostats also didnt know that you always retorque a headgasket after its first heat cycle too.
Another point of entry (including the cylinder walls) is the lower crankcase seal which is an easy change once the powerhead is lifted.

 

[Scovbert]

I was able to plain the head today, I think it came out pretty good. I missed the supply house today so I need to get the gasket tomorrow. I’m going to do both as you suggested just to check it off the list. I really don’t want to pull the power head so I’m hoping this will resolve my issues. I looked for cracks while I was in there and I didn’t find anything.

 

[Bosunsmate]

Pulling the powerhead isnt too bad, so long as you take off things like the starter, then the weight really drops and its much easier to lift. Ive swung a lassoo over a tree before and tied the other end to my car to lift up a motor.
But hopefully for your motor its just that the head gasket wasnt installed correctly. You can normally tell from looking if theres an internal cylinder leak so you have likely ruled that out

 

[Scovbert]

I was able to remove the other head tonight and have a look. The head gasket was failing. I can’t be certain that it was leaking into the cylinder, but it was clearly leaking from the water jacket. There was one spot in particular that had bulged and was allowing water to leak into the lower cowling. I picked up the new head gaskets today, I will plain this head tomorrow and reinstall everything in the next night or two. Fingers crossed that this is it. Thanks again for the help as always. Oh and what’s your opinion on using gasket sealer on head gaskets? My manual says use a light coat if the head gasket doesn’t specify. I’ve seen that some clearly say on them not to use it and also read some people just don’t think it’s necessary.

 

[Bosunsmate]

Haha it depends how im feeling on the day. Mostly mine have gasket sealant coming already on it and most often also there is a written note on one side saying face this to the crankcase or head and if thats on them then i do as it instructs. I wouldnt go putting any non specific sealant on it myself. I often dont put anyone nor has it come with any. The main thing in my opinion is torquing in the correct sequence. Ie inwards to outwards in an increasing circle and doing it in two stages, three maybe better if youve the commitment. And also retorquing to correct torque after first heat cycle has cooled down,as i mentioned previously (very important).
I often add a little bit of torque to make up for imprecisely cleaned threads and bolts

 

[Scovbert]

Welp, the head gasket job went smooth and I was very happy with how they came out but the problem still exists. Some changes in the symptoms so I’m thinking some of this work has fixed other leaks and or issues. One of the symptoms that went away was the steam coming from the exhaust ports. After I ran it I used to see steam come from the exhaust but the new thing that’s happening is when I pull the bottom two plugs smoke or steam comes from the cylinder and the plugs look wet but clean. When I pull the top there is no smoke or steam and the plugs look chared as they should. Not sure where to go from here. Any advice is appreciated as always.

 

[Bosunsmate]

did you burn the wet to check if its fuel or water with fuel?
If its fuel then you have a spark issue.
Is your rectifier water cooled?
Getting water into both bottom would be odd.
May of missed some cracks or its the bottom seal, but i cant for now workout how both could be wet with water unless cracks in both.
You could try removing the LU and running it without water for about thirty seconds and then checking the plugs

 

[Scovbert]

I did try lighting it but it didn’t light, but I also tried lighting the liquid on the plugs from the top and that doesn’t light either. The VRO has been disconnected so I run premix at 50:1. I looked for cracks with a very good flashlight and I couldn’t find any. The rectifier/voltage regulator is water cooled and brand new, I just replaced it. I’d really hate to pull the power head but maybe that’s the next step. Frustration is building.

 

[Bosunsmate]

Have you had your boat stored outside?
Shake the tank up and put some fuel in a glass. See if it separates indicating fuel and water.
It could also be stale fuel.
Yep they are frustrating, the motor i now have (a 1982 60hp) was worked on by a lead mechanic in a fairly big town. he couldnt get it work and thought it had a devil in it. He was going to try and turn ito into a million pieces due to his frustration but decided to sell it.
It took me hours to work out what was wrong with it, including having to run around the other side of the house when it dieseled and ran away on me. Eventually i found out the problem. It had atypical symptoms but it was a lower seal causing it to run lean (no water in the cylinders but that can happen).
This motor has being my one reliable thing on my boat now for ten years. Ive only had to change gear oil and impeller.
So the moral of the story is to stick with it and you can well end up with a champion.
Id let the thought of lifting the powerhead drift away for present. You really need to work out why that fuel on top isnt lighting as well (even though it is when motors ignition is working). Seems more systemic to fuel system than a seal

 

[Scovbert]

Yes I’ve had it stored outside for about a month or so now, I just bought this setup. I tried running it on the gas it came with before rebuilding the carbs and it didn’t go well. I’m currently running the motor out of a gas can with gas I bought 2 weeks ago and mixed. I also changed the in line filter. Maybe I should pull the carbs again and check the reeds? I’m just not sure. I’m running low on gas so I’ll put more fresh gas in it tomorrow.

 

[Bosunsmate]

Beats me why its not lighting on the spark plugs if it doesnt have water in it.
Id try dropping the Lu and running it for thirty seconds or so that way you dont have to have any water in the motor at all.
You could then do a drop test on each cylinder and check which ones are pulling properly. If they all are then you know its a water system issue. If its still bad then you have water in your lines somewhere.
You can also pull the lanyard line so there is no spark and turn it over a few times until the sparkplugs are dripping wet and then try and light that but from my experience normal two stroke fuel will light in an instance when a match is near it, its not at all like diesel

 

[Scovbert]

Just to be sure nothing has contaminated my gas I poured a small sample into a water bottle cap and it lit right up. I’m going to try the lanyard trick and pull the plugs and see what happens I’ll report back.

 

[Bosunsmate]

Did you do the lanyard trick with a hose connected to the LU?(or the leg in a bucket)
Itd be odd for both cylinders to have a crack. If i scratched my head itd be now.
I wonder if there was something missed in the exhaust housing area that is spraying water into both lower cylinders.
I cant think of anything further upstream that would cause water into the early part of the crankcase