56 johnson 30 hp no spark

Hi, I am working on a 56 Johnson 30 hp. It has no spark. I disconnected the vacuum valve and the wire by the throttle to eliminate them from the problem..no help. I inspected the coils..clean and have continuity. I checked the wires and have continuity. the flywheel magnet has magnetic force. I adjusted the points. I replaced 1 condensor as a guess. Still no spark on either cylinder. This motor came off a boat that had a key ign. but with no connections in place would that matter? Any help is appriciated.
Thanks!

Re: 56 johnson 30 hp no spark

What I would do is get a seloc manual, For that year engine like I did and look at the wiring dia in the back. They are really good, and the manuals have alot of good info. Check the air gap between the flywheel and the coil it makes a difference also, not sure of the spec.

Re: 56 johnson 30 hp no spark

HI scotteh. How have you tested for spark? have you used a gap tester, light tester, or held the plugs against the engine block? the spark should be able to jump a 7/16" gap or so. have you actually seen sparks coming from the plugs? thankfully, it can only be one of a few things (points, coils, condensers, s'plug wires) rather than adjusting the points you may want to clean them. very fine grit sand paper can be used to remove and crud on the points, just be sure to clean them exteremly well before you reinstall and regap them. Better still get new points and condensers (i.e. a "tune up kit") to be sure that all of your ignition parts are in in good shape. the kits themselves are only about $20-$25 and well worth the investment. I'm pretty sure you can get it right here at iboats. assuming the coils really are good, you'll essentialy have an all new ignition after you install the tune up kit. then you should be able to get sa spark with no probelm-o. good luck.

Re: 56 johnson 30 hp no spark

Scotteh said:

This motor came off a boat that had a key ign. but with no connections in place would that matter? Any help is appriciated.
Thanks!

Click to expand...

Not positive but with a keyed ignition I believe you'll have to cross a wire for the on/run switch to make contact so spark can be created???????
Get a wireing diagram

Re: 56 johnson 30 hp no spark

I held the plug against the block to test, then put a meter on it as well and got no reading. I have never seen a spark, the motor was seized and I replaced the powerhead, so I never saw it running. I am just trying to avoid getting too deep in price as I already know I need a starter. Just seems weird that both indepandant ign. have no spark and I am wondering if the key ign. I disconnected could be related or maybe even the flywheel itself?

kfa4303 said:

HI scotteh. How have you tested for spark? have you used a gap tester, light tester, or held the plugs against the engine block? the spark should be able to jump a 7/16" gap or so. have you actually seen sparks coming from the plugs? thankfully, it can only be one of a few things (points, coils, condensers, s'plug wires) rather than adjusting the points you may want to clean them. very fine grit sand paper can be used to remove and crud on the points, just be sure to clean them exteremly well before you reinstall and regap them. Better still get new points and condensers (i.e. a "tune up kit") to be sure that all of your ignition parts are in in good shape. the kits themselves are only about $20-$25 and well worth the investment. I'm pretty sure you can get it right here at iboats. assuming the coils really are good, you'll essentialy have an all new ignition after you install the tune up kit. then you should be able to get sa spark with no probelm-o. good luck.

Click to expand...

Re: 56 johnson 30 hp no spark

1956 did NOT have a keyed ignition. It is always "on". You say everything looks good under the flywheel, but obviously is isn't as good as you think. If the coils aren't cracked, somebody has already replaced them. I'd say chances are the points are not clean.

EDIT: You say it came off a boat that had keyed igniton. Well, that igniton did not come with the motor. So, no telling what you have there. Anyhoo, the motor should have spark if all that stuff is disconnected. As I said, it is always "on". Like a lawn mower, pull the rope and it goes.

Re: 56 johnson 30 hp no spark

Better check the system out really good. Often times, when people change out the coils, they don't change the spark plug leads and just shove the old leads into the new coils. In a short time, connection goes bad in here, as a result. Also, you might want to check the connections in the spark plug boots. These often fail with old spark plug leads. The little hook that goes through the spark plug lead will loose connection and the spark plug lead needs to be trimmed off 1/4" to make a new connection. The end that goes into the coil should be trimmed back 3/8" of an inch for a fresh new connection. If you replace the leads then none of this will be neccessary.
Also, the coil faces need to be lined up with the machined surfaces on the mag plate perfectly to obtain the best spark. I use a utility knife blade to check the surfaces. There should be absolutely no air gaps, from the bottom of the machined surface to the very top of the coil.
All wires from the coil need to be completely clear of the points cam, or the cam will wear through the wire insulation and kill your spark. Anytime I replace coils and ignition parts on a mag plate, I disassemble it completely and clean it up and go from the beginning to reassemble.

If you do all that, there's no reason why you won't get a spark strong enough to knock a bull elephant on his ***.