Logo

1969 Evinrude 55HP 3 cyl spark only sometimes

thommo

New member
"Hi, I have a 1969 3cyl. 55hp

"Hi, I have a 1969 3cyl. 55hp Evinrude that does not have spark at all times. It will start and run perfectly but after running for about 15 mins. looses spark (very weak) in No.1 & 3 cylinders. Spark at No.2 cylinder seems OK at all times.I have replaced both sets of points & condensers, plug leads, cleaned up all possible wiring,replaced coil. It would be appreciated if anyone could give me some advice. Thankyou"
 
"(Point Setting Of Battery

"(Point Setting Of Battery Capacitance Discharge
( Ignition Models - 1968 thru 1972)
(Some have points - Some do not)
(Joe Reeves)

The points must be set to .010 but no wider than .010..... BUT in some instances due to a possible slight inaccurately machined crankshaft lobe or a slight offset of one set of points, a setting slightly less than .010 would be required as follows.

Whether the crankshaft has two or three lobes, when setting the points, check the setting of the points on each individual lobe by rotating the crankshaft by hand.

You may find that setting one set of points to .010 on one lobe, then turning the crankshaft to the next lobe, the gap measures .011 or .012 (too wide). This is where you would need to close that gap down to the required .010. A gap too wide can result in a ignition miss when throttle is applied.

Bottom line, pertaining to the point setting at the various lobe locations____ .010, .010, .009, is okay____ .010, .010, .011 is not!

When time permits, visit my store at: http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
"Sometimes I found that wear a

"Sometimes I found that wear and radial play and un-ballance created big problems. The only solutions on old engines were to hook up a dwell meter and try to 'ballance' off the points. If loosing spark on one cyl, I 'ballanced' it off to the one(s) that worked which sometimes made the initial setting far off the .010 basic setting. A bit time consuming and only for 'special freaks'."
 
"Hi Morten, I dont quite under

"Hi Morten, I dont quite understand what you mean by "ballance" off points. I am somewhat of a novice at this but will have a go at anything. If you could explain it would be appreciated. Thanks, Paul"
 
"As I said this might be somet

"As I said this might be something for the 'freaky' ones with access to a little more than a volt meeter.
It is a question of making all points opening and closing within the same angle frame of crank shaft rotation.
I'll try just to use some numbers as example.
A working 'cylinder': Opens the points - at lobe top it opens .010 -then closes the points after a rotation of 30 degrees.
Then You might try to set another point at .010 (static), but doe to wear it only opens .005 during a 15 degree of rotation - You will be in trouble. Then if the third is set static at .010 but due to wear and tear opens .020 and at 45 degrees opening time another problem arises.
The older engines gets , the more tear and wear, the bigger the difference between static and dynamic settings. However there are limits of how much You may 'adjust' before parts have to be changed!
To do the above You need both a timing light and a dwell meter and a lot of patience. It will never be perfect, but might save You some time before changing expensive parts."
 
"Morten, Thanks for info - I c

"Morten, Thanks for info - I can understand what you are saying. Why would the motor run OK for 10-15 mins.(up to operating temp) then start to loose spark? Has it something to do with heat and expansion, bad ignition wiring etc. Any info appreciated. Thanks, Paul"
 
"I would guess 'heat and e

"I would guess 'heat and expansion' just put You on the wrong side of tolerance level. Which components is impossible to tell exactly.
You might be able to sort it out with a multimeter, but again, a time consuming job. If all cylinders starts loosing out at random, I would suspect flywheel magnetism getting low."
 
Back
Top