76 Evinrude 15 reassembled with an issue

[bktheking]

The gent who owned my 15 complained of a fouled bottom plug. When I got the motor home I checked compression, 95 top and bottom. The motor starter first pull. When I took it apart for paint I noticed that the bottom crank seal had let go, the spring had folded. So I put in a new seal and put it back together. I ran it today in the barrel and it had no power in gear, I pulled the top wire and it died yet I have great spark, points clean, plugs new, coils new, wires new even tried a different condensor. I pulled the plug after running it and tapped it on the 2x4 I was using on the test barrel, water. I pulled the head, bottom cylinder is crystal clean, much like the plug- an indicator of water. Check the head and block, no crack no nothing. Now I noticed when I spun the crank, a sucking sound with accompanying gas occured top cylinder, bottom had brown liquid laying in the bottom which I am assuming is watered down gas/oil mix but no sound on the bottom cylinder. Is the cylinder washed down? Why no sound like the top cylinder? I'm going to try the obvious head gasket. Any thoughts if the head gasket doesn't cure? Cylinder aren't scored either, could it come back to life?

 

[OLDIRON]

Re: 76 Evinrude 15 reassembled with an issue

bk, I have a 15 just like yours.I don't claim to be an expert on these but I had a similar problem.Other then the obvious head gasket,looks like you've done eveything you could. What plugs are you using? One old school mechanic that I know told me that these 15's had a very weak spark to begin with. Johnson never did get this right until they went with CD ignition. My Champions would foul out imediatly after only a few minutes in the barrel. Like you did new points,new condensers, new driver coil and new ignighter coils. The bottom plug would always look wet, not like fuel, more like water. Told me to try NGK's. Never had a problem sense.These motors seem to foul plugs. Especially Champions. I know, I know...it's what Johnson recommends. But for some weird reason, my 15 will only run on NGK's for any lenght of time. Hope this helps. These 15's are built like a tank and should give you many more years of service.

 

[Rick.]

Re: 76 Evinrude 15 reassembled with an issue

Oh boy. At the risk of sounding like a quack, here I go. I had a heck of a problem with a 79, 9.9 last spring. I had gone over it during the winter and had it running well. Took it to the lake as soon as the ice came off and it ran like a dog. No power at all. Two things were wrong in the end. I had a leak in the exhaust plate that was allowing just enough water into the lower cylinder to give it that milkish look. I had good spark but it would not fire on the lower cylinder. After I fixed the water leak it would still not fire and the plug was wet with gas. After many hours of trying different things I decided to check the reeds. Many advised it was very unlikely to be a reed problem but I had tried everything I (and others) could think of. Sure enough I found a piece of plastic stuck in one of the reeds. After that the motor ran perfect. So I'm suggesting you may well have the same two part problem as I had. The reason I'm thinking perhaps a reed is your comment about the lack of sucking sound with the bottom cylinder. Some will say the reeds almost never cause a problem and I'm sure they are right but I know I had a reed problem. Turned out the plastic was 1/4 of the end of the S.Speed knob which was missing when I got the motor. It must have been sucked in to the intake and laid there during the spring when I barrel tested it. On the way to the lake I figure it shook loose and upon starting it the plastic sucked into the reed and stayed there until I found it. Anyway, I sure hope you find your problem and wish you the best of luck with it. Rick.
Edit: I should also say I did a search to try and find the thread of my problem but cannot seem to find it.

 

[trendsetter240]

Re: 76 Evinrude 15 reassembled with an issue

Hey bk, i'm with Rick. on this one. If the bottom cylinder has compression, yet it won't draw fuel in from the crankcase it could be the reeds. If one is broken or stuck open then that might explain it.

Also I'd check the cylinder head for flatness with a straight edge and feeler gauge.

hth, cheers.

 

[bktheking]

Re: 76 Evinrude 15 reassembled with an issue

Rick I found your thread last night and read it, I agree, the lack of noise is quite strange, I'm almost tempted to pull the powerhead and rebuild it. As far as NGK plugs, that's what are in it and it still has an issue, there is no doubt that it is water. The exhaust tube has all new seals so I know it can't be that. I guess i'll start with head gasket and pull the intake to check the reeds, I have a spare set here off another motor. As far as spark, I hooked up the tester and ran the motor on one cylinder, in clear daylight I could see spark jumping around a 50 thou gap which is good for the breaker setup.

 

[bktheking]

Re: 76 Evinrude 15 reassembled with an issue

Head and gasket , the part I circled is where I believe the water intrusion was happening.

Here is the water inside the bottom piston, nice light brown mix.

Upon closer inspection, the top of the water tube grommet is missing, thinking water could be entering there as well. The new seal was the bottom one.

 

[bktheking]

Re: 76 Evinrude 15 reassembled with an issue

As far as reeds, well, here you go

Something just didn't seem right with the sound and your hunch was correct, I couldn't believe my eyes when I took the intake off. Rule of thumb to all the maintenance boys in here, get rid of zip ties when you cut or take them off, this is what happens, hard to believe

 

[McGR]

Re: 76 Evinrude 15 reassembled with an issue

Wow! Good call Rick.

 

[jasper60103]

Re: 76 Evinrude 15 reassembled with an issue

Wow! Good call Rick.

I agree and thanks for sharing, BK

 

[Rick.]

Re: 76 Evinrude 15 reassembled with an issue

Well now I don't feel like such a quack anyway. I'm so glad you found your problem even though I know it was a long shot with a fair amount of work that might not have paid off. I know I was close to tears with mine last spring but now it works as an Evinrude should. Looks like another Evinrude has been saved which makes me very happy. As always, best of luck to you. Rick.

 

[bktheking]

Re: 76 Evinrude 15 reassembled with an issue

Thanks again Rick for your suggestion, I thought along the same lines as you with the reeds just didn't think a bloody zip tie could get sucked into the carb. Parts are on order, can't wait to see how it runs now that it can get fuel into the cylinder.

 

[jmendoza]

Re: 76 Evinrude 15 reassembled with an issue

Good call senior Rick! When I have the plugs out for service, I always flip the engine over and check crankcase compression. There is no specification for this, but it is so critical to any 2-cycle's opperation; it has to be able to pump in air to the cases and cylinder to run. I listen for the "thooopah-thooopah-thoop" noise each cylinder makes as the reeds open and close and the slight resistance you feel as each piston goes on the downstroke while pulling the rope. On a good engine, just turning the flywheel by hand a half turn should result in wheezing/honking sounds from the intake as the reeds open alternatively.

That upper water tube grommet often leaks when they get over ten years old, pretty common. I stocked up on 3 of them, as some day they will no longer be availlable.

 

[OLDIRON]

Re: 76 Evinrude 15 reassembled with an issue

Bk,glad you found atleast a good part of the problem.Head gasket for sure. But that zip tie...that's just insane. That thing had to jump into the air silencer, past the choke plate,past the throttle butterfly,through the carb body to get wedged in there.Besides that,it's a white zip tie. And all the ties on my 15 fuel lines,or anywhere for that matter, are black. I think someone sabotaged your motor.Or the PO did something very very stupid.

 

[bktheking]

Re: 76 Evinrude 15 reassembled with an issue

I bought it for $75 running and shifting, he warned me when I bought it that it was fouling the bottom plug. I've got $75 into it so for $150 I'm not going to complain!
I couldn't test it last night cause it was raining cats and dogs, hopefully tonight.

 

[bktheking]

Re: 76 Evinrude 15 reassembled with an issue

Fired it up as soon as I got home, 1/4 throttle launched water out of the barrel, runs like a champ now! These little 15's seem crazy powerful.

 

[CatfishMN]

Re: 76 Evinrude 15 reassembled with an issue

Fired it up as soon as I got home, 1/4 throttle launched water out of the barrel, runs like a champ now! These little 15's seem crazy powerful.

I agree. My buddy has had one on his river boat for years and the thing is indestructable and can really push the boat!

 

[Rick.]

Re: 76 Evinrude 15 reassembled with an issue

bktheking thanks for letting us know. I have been wondering and it sounds like success has been accomplished.

My first ever outboard I owned was an 82 - 15hp. Up until then I new nothing about them and to be honest I don't think I had ever touched an outboard let alone worked on one. I spent a few bucks on parts and got it running perfect and then gave it to a friend as I didn't even own a boat. Well long story short I have a boat now and last year the friend gave the 15 back to me so it is now my main motor and it still runs great.

If it weren't for this forum I doubt I would have had the courage to try and get it going on my own. This forum is so vital. It's sort of like not being able to swim and knowing there are many " LIFE GUARDS ON DUTY " who are so willing and eager to lend a hand when we might drown otherwise. bktheking you have helped so many on this forum and I'm just glad I was able to Lend a Hand to you. Rick.

 

[bktheking]

Re: 76 Evinrude 15 reassembled with an issue

Hey thanks Rick, I really appreciate the insight on this little project, have to admin the zip tie/reed plate really through me for a loop. You've helped me before which has been invaluable. I've learned alot working on them, this has been my 3rd teardown and partial rebuild, I'd like to eventually build a 9.9/15 racer, a buddy here in town can balance and blueprint and I hope to have him teach me how it's done.