'68 33hp johnson won't start with plugs in

[Jim1942]

The starter on my 33 hp Johnson spins the engine fine with the plugs out. When I put the plugs in the engine balks and will not turn over. Any suggestions.

 

[Paul Moir]

Re: '68 33hp johnson won't start with plugs in

Check the voltage at the starter itself when you crank the engine over. It should be no lower than about 9v.<br />Can you turn the flywheel by hand through a complete revolution?<br /><br /> Engine will not Start FAQ<br /> <br /> Electric starter FAQ

 

[DJ]

Re: '68 33hp johnson won't start with plugs in

Did this engine backfire or sneeze before this trouble started? If so, you may have sheared the flywheel key thus throwing he timing off.

 

[Paul Moir]

Re: '68 33hp johnson won't start with plugs in

Broken flywheel keys on magneto ignition engines like this one causes weakening or loss of spark rather than bad timing, since timing is ultimately taken from the crankshaft cam rather than the flywheel like on modern outboards. <br />But that's a really good point. Other things that can throw timing off:<br />1) Armature plate sticking - it's the part up underneath the flywheel that the spark plug leads run to. It should turn smoothly with the throttle.<br />2) Armature plate loose. I think it would have to be very loose.<br />3) Misadjusted points.<br />4) (most commmon) Spark plug leads on backwards.<br /><br />Hope this helps!

 

[Jim1942]

Re: '68 33hp johnson won't start with plugs in

Thanks for your help. Got it started, but have a few questions. How do I wire the cutout switch and neutral switch in-line? Which side of the selenoid is start and what is the other side. I have an automtive type selonoid. And last, What causes a coil blow out on maget side? Thanks again, Jim

 

[Paul Moir]

Re: '68 33hp johnson won't start with plugs in

You've got the wrong solenoid. You need one like SW622 here. <br />Blown up ignition coils are caused by connecting 12v to the ignition system. The battery and ignition system should be completely separate.<br /><br />The proper wiring for the cutout, solenoid and safety are as follows:<br /><br />Key switch (S) position -> one small lug on the solenoid.<br />Other small lug on solenoid -> base of vaccum cutout switch.<br />base of vaccum switch -> neutral saftey switch.<br />neutral saftey switch -> ground. <br />Top centre post of vaccum cutout switch -> one magneto lead from beneith the flywheel.<br />Top centre post of vaccum cutout switch -> One key switch (M) position terminal or kill switch.<br />Other magneto lead from beneith the flywheel -> other key switch (M) position terminal or kill switch lead.<br /><br />Check to be sure your vaccum switch is not shorted somehow (you'll have to disconnect the leads from it to find out). That in combination with using an automotive solenoid will cause a coil to pop if your wiring is correct. Check your neutral saftey switch too - it could have been fried by the incorrect solenoid as well. Order a repair manual from this site or an OEM one from one of the following locations:<br />TheOutboardWizard<br />Mastertech<br />Marine Engine<br />Ken Cook <br />Iboats sells new ignition coils, pn 18-5181 cheap.<br /><br />Correct solenoid schematic:<br />

<br /><br />Incorrect automotive type solenoid:<br />

<br /><br />Hope this helps!