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1958 Johnson, won't fire up

donofish

New member
I have aquired an old mahogany runabout that I am restoring. It has twin Johnson 35HP RD20, 1958 motors.
I have rebuilt the carbs and fuel pumps and checked the compression 115 on both cylinders johnson #1, and 120 lb on both Cyl. of Johnson #2

I have #2 in a test tank, It cranks over and seems to be getting gas, I have a light blue spark but will not pop.

What should I try next?

Thanks,

Donovan
 
Remove the flywheel in order to check the coils etc. A light blue flame is not enough. With the spark plugs removed, the spark should jump a 1/4" gap on that model with a strong blue lightning like flame.... a real SNAP! Note that checking spark by using the spark plugs is a waste of time.
 
(Regular Magneto Coils - Continuity Test)
(J. Reeves)

Checking the continuity of the ignition coils....... Have the ohm meter set to High Ohms.

Remove the primary wire from points. Remove the coil ground wire. You do not want either of these wires touching anything.

Connect the black lead of a ohm meter to the spark plug boot terminal, then with the red ohm meter lead, touch the ground wire of the coil.

Then touch (still with the red lead) the primary wire. You should get a reading on both touches (contacts). If not, check the spring terminal inside the rubber boots of the spark plug wire.

If there is no continuity between the secondary circuit (spark plug) wire and the primary or ground, remove the coil from the armature plate, then check the continuity directly between the prong within the coil (prong that the plug wire connects to) and the primary and ground. Poor or no continuity of a coil (or plug wire) is one reason for weak spark, s/plug fouling, or no spark.

(Magneto Coil Alignment)
(J. Reeves)

To align the coils properly, have the metal vertical portion of the coil yokes aligned with the inside edge of the bevel that exists on the top portion of the aluminum seat upon which the coils sit. This creates the proper distance between the coils and the flywheel magnets. Faulty alignment creats friction and the yokes of the coils heat up, turn blue and expand.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay store at:
http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store

(Point Setting Of Magneto Models)
(J. Reeves)

Set the points as follows. Have the flywheel key aligned with the fiber rubber portion of the ignition points. Adjust the gap so that a .020 gauge will pass thru but a .022 will not. Should there be any question of the points being dirty (touching the contact with your finger would cause them to be dirty), clean them with a small brush and acetone or lacquer thinner.

NOTE: Should the operating cam have a small portion on it with the word "SET" imprinted, align this portion with the fiber rubbing portion instead of the flywheel key.

Thousands of parts in my remaining stock. Not able to list them all. Let me know what you need and I'll look it up for you. Visit my eBay store at:

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store
 
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