No spark problem

TinBoats.net

Help Support TinBoats.net:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

dieselfixer

Well-known member
Joined
Feb 15, 2011
Messages
153
Reaction score
0
Location
Barker NY
I am working on a 1960 Johnson 3hp the original coils were completely shot, so no spark. I replaced the coils, points, condensers, spark plug wires and plugs. Still no spark, all the new parts have been tested using a digital ohm meter and all appear to be ok the coils are properly adjusted. Any help would be great as I am at my wits end.
 
Need more information.
What is your points gap?
Did you make sure the wires from the coils that go to the points are tucked out of the way of the rotating cam?
Please tell me you didn't use aftermarket coils.........
Is your cam in place? Right side up?
How are you checking spark?
You replaced the coils but not the wires? Wires may be arcing to ground if they are 57 years old. Replace them as well as the plug boots which are also available.
This is a good start.
This engine needs to be run on no less than a 24:1 fuel oil mixture by the way. Definitely not a 50:1 engine no matter what your buddy told you.....!
 
Thank you all for the replies. Pappy the points are set at .020 the word top is visible on the cam the points were set with the end of the point arm in the area of the cam marked top the coils are sierra brand I replaced both spark plug wires and spark plugs I am using an inline spark tester that has been tested using my chainsaw all of the wires were routed away from all moving parts. I cleaned all grounds with scotch pads and brake cleaner. There is no switch on this engine when the throttle lever is moved to stop I think that the timing is so far out that the engine cant run
 
Possibles here.
One.....the Sierra coils suck! Sorry for being blunt.
If you still have one of your original OEM coils grab it. Pull the Sierra coil easiest to pull as well.
Place them both inside the flywheel where they are seated against the radius of the flywheel (like they would be in a running position). Now....look at the air gap on the Sierra coil compared to the OEM coil. It does not fit the flywheel radius like it should.
The Sierra coil at the center laminates is quite a bit farther away and will produce less than a new OEM will. The old OEM should almost have zero air gap and fit quite well in comparison.
Two.....flywheel magnet strength. Could be weak and need a charge. This will make the coil issue even worse. Check with a screwdriver. It should slam the shank against the magnet.
Points cam have a key to rotate it?

Arcing to ground.
Hey, it's night time. Go out and with the spark plugs out see if the ignition is working and going to ground somewhere. Should be able to see it in the dark.
This ignition system should jump no more than a 1/4" air gap.
 
Pappy The cam is keyed using the flywheel key, the flywheel magnets have plenty of power and will stick a screwdriver very well. I have had doubts about the Sierra coils for some time now and will get 2 oem coils. I tried to see any grounding spark last night as you suggested didn't see or hear anything. I will install new oem coils and report back. Thanks for the help.
 
Always clean new points. They build a layer of hard corrosion or have been sprayed with a protective coating that needs to go. You are asking a weak sauce, non battery powered ignition to connect thru that invisable layer. Can you even buy new points today that don't suck? Hang on to your old ones.
 
I used a point file and a little brake clean on the new points before I installed them. I am going to save the old points and condensers, just because a part is new doesn't mean it is any good these days.
 
Stumpalump said:
Always clean new points. They build a layer of hard corrosion or have been sprayed with a protective coating that needs to go. You are asking a weak sauce, non battery powered ignition to connect thru that invisable layer. Can you even buy new points today that don't suck? Hang on to your old ones.

Yes....unlike the Sierra points the OEM point sets (580148...I think) line up perfectly and will last. They are still available and well worth it.

By all means...stick the old points sets back in and clean the surfaces with something like 400 grit. They should be fine. New condensors are a must. Again...OEM is the way to fly on these parts.
 
I installed 2 new oem coils and condensers, cleaned and checked the old oem points they look as good as new so I reinstalled them. The oem coils fit much better than the Sierra ones, I adjusted the coils to .005 air gap. I now have spark, now if the carb is working the engine should run. If I need parts I know what brand to get. After 42 years of working on heavy duty diesels you would think I would know better than to buy aftermarket parts. Thanks to all who replied.
 
dieselfixer said:
I installed 2 new oem coils and condensers, cleaned and checked the old oem points they look as good as new so I reinstalled them. The oem coils fit much better than the Sierra ones, I adjusted the coils to .005 air gap. I now have spark, now if the carb is working the engine should run. If I need parts I know what brand to get. After 42 years of working on heavy duty diesels you would think I would know better than to buy aftermarket parts. Thanks to all who replied.

Never too young to learn something new. I get hit in the face with the new stick so much I just say thank you sir may I have another.
 
Check the gear lube and replace the impeller at the very least.
The floats were cork and you have a chance it will be good to go. On that engine, with the lower cowl off you can pull the carb bowl and see what you have to deal with.
Pull the cap off the tank and make sure the vent (tiny hole) is open all the way through. A fine wire should go all the way through. Free flow some fuel through the copper line to make sure it is clean and clear.
 
Pappy I filled the lower unit and flushed out the fuel tank and line with mineral spirits. Does this engine have a pee hole for the water or does it exit from the vents about 1/2 the way down the shaft? I haven't seen anything that looks like a pee hole. I am planning to change the gear oil and impeller after I get it to run. This engine belongs to my sons father in law and it was his Dads so it is important to make sure that everything is in good shape.
 
There is no tell-tale. Down near the water line where the slots or holes are is where you will see the water exiting the exhaust housing. Not much water as it is just randomly blown out by the exhaust pressure.
If I were you I would get the impeller on its way..... These little fellows run on the warm side anyway and if the blades break off it will self destruct pretty quickly so beware and do not run it long.
If you are a good "tuner" you can get one of the JWs to idle down low enough to where you can actually place a finger on the flywheel and let it rotate with the engine!
Not recommended of course [-X [-o<
 
Pappy The oem water pump parts are on the way. We ran the engine for about 10-15 minutes and always had water spitting out, we got it to idle down pretty slow, after we fix the pump we will run it longer and see how slow we can make run. It is a nice smooth running engine. Thanks for all the help
 

Latest posts

Top