1961 Johnson Seahorse 75hp no spark V4SL

[Clippership821]

I put new points, condenser and rotor in 2 years ago. She was running great then died in the water at about WOT. Now, no spark. plugs look good. Could it be the condenser and how do you check that? Thanks

 

[Evinrude Boater]

Re: 1961 Johnson Seahorse 75hp no spark V4SL

Ignition tester, got one? If you do it's probably dusty. Have you taken the distributor off to inspect the condition of the points and wires? Could be dirty or even rusty.

 

[lindy46]

Re: 1961 Johnson Seahorse 75hp no spark V4SL

Check your kill circuit. There are two wires coming from the points which, when you turn the key off, ground the points. If the insulation is worn, could be grounding out somewhere. Or switch could be bad.

 

[Chris1956]

Re: 1961 Johnson Seahorse 75hp no spark V4SL

Clipper, There is a condenser test. You must have both sets of points open to do it. Remove point wire from dissy housing. Set both points open. Using an analog multimeter, set at RX1 Ohms scale, charge the condenser for 1 sec (red lead to points lead, black lead to ground). Now quickly switch the leads and set scale to DC voltage. You will see a small spike of voltage, if condenser is good.

It is more likely that the wire connecting the two sets of points shorted or broke, or that the coil is bad. You might check tham out as well.

 

[Clippership821]

Re: 1961 Johnson Seahorse 75hp no spark V4SL

Thanks for all the input. Looks like a got a few things to look at. This engine has a distributer magneto so at last I can rule out the coil..doesn't have one. The manual mentioned something about a sheared woodruff key. But, that sounds like it might be a hassle to change. So, I'm keeping my fingers crossed that it's in the magneto. Tx again...I'll keep you posted.

 

[Evinrude Boater]

Re: 1961 Johnson Seahorse 75hp no spark V4SL

There is a coil inside the distributor. Take the black distributor cap off and look up under the distributor. If the flywheel key was sheared it would probably backfire. In any case, you can look down the slot. You probably can't tell if it has sheared since half would still be in the groove. You need a good heavy puller (harmonic balancer puller) and high strength bolts to pull the flywheel and a good sized torque wrench to put the nut back on. If not tightened to spec it can shear again.
Go over the distributor and spark plug wires first.