1976 Evinrude 15655a 15hp no spark

[Crosbyman]

http://www.youtube.com/watch?v=ga1Cjymj6ms&feature=youtu.be

this may help also

 

[F_R]

It would be extremely rare to find weak magnets made since WWII. They just don't go bad, short of running it through the smelter.

 

[racerone]

F_R----I have to agree on the magnets not going bad.-----There are lots of folks that are taking a stab in the dark at what may be wrong.----Testing the parts is the way to go.-----Test or have the driver coil tested !!-----Let us know if that item is good or bad.

 

[Cdubb2010]

Per my eye I see nothing wrong. I didn't have a file on hand so 1000 grit sand paper was used, lots of junk came off and it was cleaned with alcohol on a business card. My logic is that if my clean job wasn't perfect I should still have some spark if nothing else is wrong.

The open air test is explained well, don't have one of those but I'm sure I can locate one. By chance is this something an auto parts store would rent or sell? My question is the open air test how I would go about testing the driver coil? If not what's the procedure for that?

 

[Cdubb2010]

I did do a compression test, with four pulls it was at 74 and climbing on both cylinders. Haven't tried the starter yet, would a 200 cranking amp lawn motor battery be ample for testing?

 

[F_R]

I'm sure there is a better way of testing the driver coil than what they used back in 1976 (now obsolete). So I won't comment on that except to say the resistance spec is 2.7 =/- .7 Ohms across the winding and infinity to ground. I would say that you probably could buy a spark checker at an auto parts store, but I've had mine since the 1950's so haven't gone shopping for one.

OK, so you said you cleaned the points, so I won't dispute that. But if you have a decent multimeter, check the resistance across them (with wires disconnected). Resistance should be zero Ohms on your lowest test scale. Not one Ohm, or half an Ohm, but zero. Otherwise, it won't have spark.

 

[oldboat1]

Spark testers are cheap (auto parts store). If it breaks, buy another one. Checking the magnets is similar to a myriad of other cheap simple checks. There is no probability calculus involved unless there are costs attached -- no reason not to check.

For spark and compression testing, crank with the starter if it works. If not sure about the starter, can jump direct from the battery to test (positive stud on the starter, negative to the bracket). A 12v lawn mower battery can work.

 

[OptsyEagle]

No Title

OK. So the picture below is a homemade spark tester idea that I think I got from FR, but in any case, works just great. I built the exact model and have been using it for years. Set the distance between the top plate and the bolts to around 3/8". Ground out the top wire on the motor and place the two spark plug boots on the bolt ends and if you see the sparks jump, you are good to go. May need a second person to hold the tester and if it can be done in a dark room, all the better.

Now if you don't have spark on both cylinders then you can temporarily rule out things that are cylinder isolated. You want to first look at things that would take all both sparks at the same time. Obviously the driver coil is one of those culprits. I have no idea how to test it but I am sure a search here, youtube and the entire web should give some idea. I would then want to make sure the whole system is completely grounded. Lastly, you are pulling hard on that flywheel I hope. An engine's ignition system requires a minimum RPM to create the voltage require to spark a spark plug. I think anything less then 300 RPM would put your spark in jeopardy.

I would also test the continuity of those points individually. Although we are looking for a problem that would take out both sparks at the same time. Perhaps an improper cleaning may do that. Never hurts to see if they will conduct electricity.

 

[F_R]

On that system, one set of points not making good contact can kill the sparks on BOTH cylinders. One set of points grounds one end of the driver coil, while the other set causes it to fire when they open.

That is unlike the Universal Magneto where the points are each for their respective cylinders. I might add that the condensers are more critical on this system.

 

[boobie]

F-R, The comment you made here is the most important anybody has made about the regular magnetos and those damned low tension ones. Remember, low tension causes hypertension. Very true.

 

[Cdubb2010]

Alright guys,

Lots of great advice here but this motor has throughly kicked my as$. I still haven't traced it down and I need it to be 100% right in the spring time or to find one that is for my boat by then. So now the question is now how much is reasonable to spend on repairs? I'm going to take it to a old timer who used to run a marina who still tinkers some, I have no idea his labor rates but I bet it's less than elsewhere. I got $250 in it right now, would another $250 spent to make it 100% right be justifiable? I see running 2 stroke long shaft 9.9 and 15s go for 500-700 when I come across then and it does sound like this model is a pretty good one to have. If it was yours where would you draw the line at?

 

[racerone]

Difficult to say without pictures of this motor.----Overall condition matters.----Electric start / charging is a bonus.-----What about the lower unit ?--They can also be expensive to repair / reseal.---Myself I have all the pieces to repair a few those motors without spending a penny. ----Get that fellow a case of suds and ask for his opinion.---In your area like Ontario there are still lots running very well.---Not much use for them this time of the year.