1978 Evinrude 55hp two stroke not running

[bbben0721]

New to the forums and looking for some advice on a weird issue as I am running out of ideas. The issue is as follows: I have a 1978 Evinrude 2-stroke 55hp outboard motor that has been running great for some time now and really hasn't given me any issues at all. Took the boat out this morning and it started up great as usual and then we shot across the lake and turned the motor off. Long story short the motor would not start and was getting fuel but seemed not to be getting a spark. Took the plugs out cleaned them off and put them back in and it started up great, ran, turned it off and back on a couple more times and it was fine. Took it back to the lake and would not start and gave me the same issue where it was getting gas but seemed as if it was getting no spark, brought is back home and it was getting spark for sure but still not starting. Looking to see if anyone has had a similar issue as I can't think of what is going wrong since it ran fine at the house but then for some reason would not start at the ramp or at the house again. Any troubleshooting tips would be greatly appreciated.

 

[Joe Reeves]

Remove the black/yellow wire (kill circuit) from either the ignition switch or the powerpack, whichever is easiest. Test the spark. If you now have spark with that wire removed, and NO spark with it connected,, replace the ignition switch

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The spark (with all spark plugs removed) must jump a 7/16" gap with a strong blue lightning like flame... a real SNAP! Testers available at auto parts stores or build the following. NOTE that checking the spark by using the spark plugs is a waste of time!.... The 7/16" air gap is important.

(Spark Tester - Home Made)
(J. Reeves)

Most auto part stores have "air gap" spark testers... OR..........

You can use a medium size philips screwdriver (#2 I believe) inserted into the spark plug boot spring connector, then hold the screwdriver shank approximately 7/16" away from the block to check the spark or build the following:

A spark tester can be made with a piece of 1x4 or 1x6, drive a few finishing nails through it, then bend the pointed ends at a right angle. You can then adjust the gap by simply twisting the nail(s). Solder a spark plug wire to one which you can connect to the spark plug boots, and a ground wire of some kind to the other to connect to the powerhead somewhere. Use small alligator clips on the other end of the wires to connect to ground and to the spark plug connector that exists inside of the rubber plug boot.

Using the above, one could easily build a spark tester whereas they could connect 2, 4, 6, or 8 cylinders all at one time. The ground nail being straight up, the others being bent, aimed at the ground nail. A typical 4 cylinder tester follows:

..........X1..........X2

.................X..(grd)

..........X3..........X4
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Inspect the stator under the flywheel visually, closely! Should there be a sticky looking substance leaking from it, dripping down on the powerhead area, replace the stator.

 

[oldboat1]

but seemed as if it was getting no spark, brought is back home and it was getting spark for sure but still not starting.

Buy an adjustable, open air spark tester and see what you have -- cheap, with dependable results. Post findings.

 

[bbben0721]

Thanks for the info. I will be testing shortly and posting with my results.

 

[bbben0721]

Ok. After thorough testing of the ignition system everything seems to be fine and and working order. There were several wires that needed attention so I repaired them. Hooked up the hose and she fired right up. Trailered the boat to the lake and it wouldn't start again. Just kept turning over but not running. Took it back home and it started and ran fine again... Decided I would run some seafoam through the system and see what would happen. Looks like the problem must have been in the fuel delivery area since after running the seafoam through for 15 min letting it sit then running for another 15 min the boat starts not only at the house but at the lake as well.. Even sounds like it's running better. Don't know where the issue was which scares me, but everything is fine now and we took the boat out four times this weekend with no problems. Thanks for the advice from everybody as it did help me eliminate a possibility for the problem.

 

[Joe Reeves]

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(Engine Won't Start or Hard Starting In Water)
(Joe Reeves)

The Evinrude and Johnson engines, starting in 1973, have what is called Magneto Capacitance Discharge ignition, self contained, not dependent on battery voltage. The engine must turn over at least 300 rpms in order for the flywheel magnets rotating past the stator ignition generating coils to supply approximately 300v AC to the powerpack(s), which in turn is needed to supply power to the coils etc etc (spark).

In the water, exhaust back pressure is encountered due to the fact that the exhaust housing (housing between the powerhead and the lower unit) is filled with water. This would drag down the needed rpms, affecting ignition.

Normally the clue to this type problem is that the engine starts fine on a flushette (hose), but is very difficult to start when in the water.

Should this be the case, check the battery, clean and tighten all conections (use a wrench or pliers, not your fingers). Any cable that gets overly warm or hot indicates either a loose, or tight but dirty, or internally corroded cable. And of course check the starter itself.

 

[bbben0721]

All connections are cleaned and properly tightened. There were only a few with some corrosion but other than that everything is now correct. I brought the boat to the ramp and it started up fine with no issues. Then we moved to our fishing spot, stopped the motor, started the motor, moved to another spot, and then when we went to start the motor it just cranked and wouldn't start again. Brought her home and she still wouldnt start. after sitting for about 30 minutes she started right up. Is there any test anyone knows of using a voltmeter or ohmmeter to check the stator? Any thoughts?

 

[racerone]

I would start with an inspection of the STARTER MOTOR.---easy to do and may just need new brushes.

 

[trailking82]

For test with a multimetter on the electronic side of the motor go over to CDIelectronics. They have some really great troubleshootings

Also check your compression numbers again and post them here.

 

[oldboat1]

Did you test and measure spark yet?

 

[bbben0721]

The spark checked out fine as well as the starter. I'm beginning to think it has to do with something related to backpreassure on the exhaust as mentioned previously... Everything works fine when hooked up to the hose but as soon as the lower unit/shaft is submerged in the water it will only turn over. Could carbon build up in the exhaust shaft cause this?

 

[bbben0721]

And as of now the motor will only run on the hose. I cannot get it to run when submerged at the ramp at all anymore. When it's running on the hose it idles and revs perfectly and will stay running until I turn the key off as expected.

 

[racerone]

You are missing the point !-----There is something wrong with the motor !-----They all sound good on a hose to the untrained ear.----Post actual results of tests then and only then can experts lead you in the right direction.

 

[Joe Reeves]

You are missing the point !-----There is something wrong with the motor !-----They all sound good on a hose to the untrained ear.----Post actual results of tests then and only then can experts lead you in the right direction.

Probably be okay if he had a extremely long hose.

Seriously... if the engine actually does run okay on a hose but won't start in the water...... bbben0721, re-read post reply #6. Also, visually and closely inspect the stator to see if possibly a sticky looking substance might be dripping down on the powerhead area, and if so, replace the stator regardless of whatever reading you may get out of it.

 

[bbben0721]

Ok. Well I meant to post compression test results earlier but for some reason it did not post. They are as follows: when cold I was getting about 105 psi. Then after reinserting the plugs, running it for 5 minutes, then removing and testing again I read about 120 psi. The stator is not leaking any sticky looking substance either. And sorry for my lack of knowledge but that's the reason why I came to the site.

 

[racerone]

Compression should be 140 + on these models.