service manual for 1975 15hp evinrude?

stackz

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anyone know where I can find one online? local library copy is apparently eternally checked out.

I'm trying to trace the engine grounds and such as I have a no spark situation. also, plug gap specs, etc, etc. just trying to cross all my T's and dot all my I's...

found this link:

but nothing shows and it wants you to sign up for a website...

I also tried looking in the sticky "secret file" section but all the links are goofy...the points/condensor one is an ice fishing thread? lol


edit: ooo I think I found it! (edit again...nope!)
 
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OptsyEagle

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No online manuals that I know of. Perhaps others might know. This site gives a lot of info on repairs for outboards. Indispensable for the DIY outboard mechanic.

As for spark. 99% of the time, if that motor has not been used in a few years, your points are corroded. You will need to pop the flywheel and finely sand them, then blow them with compressed air. Then use some lacquer thinner on a clean business card to pull through them to get out any oils that might be on the points. Blow them again. All this after you set their gaps to 0.020".

That model of motor does not like champion spark plugs. If you troll a lot, and you should not with that motor, you should use NGK B7HS spark plugs to reduce fouling. That motor prefers to be running full out so make sure you do that before you come into the dock. Replace the spark plugs after a few seasons to prevent dropping a cylinder now and then from fouling.

Other then that, you have a great motor there.
 

stackz

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You will need to pop the flywheel and finely sand them, then blow them with compressed air. Then use some lacquer thinner on a clean business card to pull through them to get out any oils that might be on the points. Blow them again. All this after you set their gaps to 0.020".
this is some of the info I was looking for. yeah, the gaps are massive on the points lol. well over .020...

I'm trying to figure out how to test the coils and condensors. I found the grounds and cleaned them all up. the videos I see on youtube for the condensors want you to use uF scales and my digital harbor freight multimeter doesnt do this.

I did find this video but my attempt to do what the guy did was inconclusive at best...

you happen to have the specs on the coils?
 

stackz

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I mean overall there's nothing to this thing electrically. magneto to coils and then to the kill switch. bypassed the kill switch. cleaned the magneto ground and coil grounds...sanded the points and set them to .020...tried to check the condensors and they both sit around .02 (no 0 or infinity) so I guess they are good?
 

stackz

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hmmm...making progress. no spark on top cylinder but looks like fat yellow spark on the lower one. for cars that would be a weak spark but not sure on this little thing?
 

stackz

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Does spark jump a gap of 5/16" on a test device, yes or no ?
the lower plug will jump the gap on the autozone spark tester I have but as said earlier, its a fat yellow/orange spark which is weak.
 

racerone

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Swap the coils and repeat the spark test with a 5 /16" gap tester.----Not a blinking light thingy.----Post what you see.
 

stackz

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Swap the coils and repeat the spark test with a 5 /16" gap tester.----Not a blinking light thingy.----Post what you see.

I mean if I have to keep buying tools just to troubleshoot this engine, I'll just pull it off and put the 95 gamefisher 15hp I have on the boat. I wanted to keep this engine though as its original to the boat and I consider it "part of the pair" that inherited from my grandfather.
 

racerone

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You can make a simple test device with some wires and a piece of scrap plywood.----no beer tokens spent.
 

OptsyEagle

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LIke this, made out of wood. Metal at the top with a ground wire connected to the engine ground. Adjust the bolts for the gap you want between the bolts and the metal above it. Put the spark plug boots on the bolts. Pull the starter rope and watch to see alternating sparks. A dark room helps with this test.
 

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jimmbo

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Both electrodes work better if they are small and have sharp Edges
 

stackz

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I just went ahead and ordered a spark gap tester off amazon (adjustable one) and it should be here tomorrow. I will go outside shortly and see if swapping coils causes the spark to move or not. if it moves, then the coil is bad right? if it doesnt then its likely the points or condensor right?

also, been doing more reading on the links from above and I'm interested in the conversion away from points. the link provided goes to a product page that is empty though and then when I click around on that site, it comes up with something that looks completely different from what is shown on the link?

 

stackz

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I swapped the coil lead wires and spark went from the lower cylinder to the upper cylinder so I assume both coils are good. I popped the wiring loose from the points and coils and ohm'd the wiring and that is good. I assume one of the condensors is bad. will play with that later on. I also noticed that on the wiring side of the coil plug portion of the harness, the wiring is frayed as well so I guess I will start looking for a good used harness as I dont believe I will find these particular odd looking pigtails anywhere?
 
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