Spark Issue on 1970 Johnson 85hp

smoke14

Cadet
Joined
Feb 22, 2010
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20
Had no spark out of coil , replaced coil and ampliphier now getting spark when starter engages and when starter disengages but not when engine is turning over. It has a very bright strong spark jumps over a 1/2 inch when it does spark. I rechecked all connections, grounds are clean and tight. Any direction would be helpful
 

perkdp

Petty Officer 1st Class
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Sep 25, 2002
Messages
237
Re: Spark Issue on 1970 Johnson 85hp

How do you know the coils are firing witout the starter spinning the motor ?

What ignites the starter a button or key ? Could the contact side of that switch be crossing the "kill wire" sending the coil to ground ?
 

smoke14

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Feb 22, 2010
Messages
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Re: Spark Issue on 1970 Johnson 85hp

I have the spark tester hooked up after the coil, I turn the key over to start the engine as the starter engages the engine and starts to turn there is a bright spark from the spark gap tester, then it stops as the engine is turning. as I release the key to stop trying to start it, another spark will happen at the tester then the starter disengages.
 

smoke14

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Feb 22, 2010
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Re: Spark Issue on 1970 Johnson 85hp

Could really use some advice!!! Going to pull the flywheel today and check the points out. I have spent hours looking for the part # to purchase new points to no avail. ishopmarine.com shows them but states they are no longer available. I tried to cross reference the part # and that doesnt work?? getting frustrated with lack of information.
 

smoke14

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Feb 22, 2010
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Re: Spark Issue on 1970 Johnson 85hp

Removed the flywheel, cleaned all contacts, filed the points and reset the gap to 0.010 reinstalled everything and still turns over no spark. one question I have if you squeeze the fuel bulb should it get difficult to squeeze? on this boat it never seems to pump up? just another issue to deal with :mad:

Could the assembly be bad? How do you test something that is under the flywheel?
 

smoke14

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Joined
Feb 22, 2010
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Re: Spark Issue on 1970 Johnson 85hp

Wow 50 reviews and one person has info :confused: I must have a one of a kind outboard engine.
 

kenmyfam

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Aug 10, 2006
Messages
14,392
Re: Spark Issue on 1970 Johnson 85hp

Fuel bulb does not have to be rock hard.
What was the condition of the points ?? big build up and hollow ???
You may have stoned through the case hardening of the contact surfaces. Screws things right up although the gap may appear good.
 

smoke14

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Feb 22, 2010
Messages
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Re: Spark Issue on 1970 Johnson 85hp

Thanks for the reply, did not see any build up, just slightly touched em up with a points file just to make em shiny.
 

F_R

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Jul 7, 2006
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28,226
Re: Spark Issue on 1970 Johnson 85hp

OK smoke, let's make some sense out of this thing. What you need to do is check the voltage at the amplifier input while the starter is cranking. If it is too low, or not at all, there is your problem. A bad key switch can cause either problem. If present but too low, could be battery cables, starter drawing too much current, bad wiring, or whatever.

Whatever, get a voltmeter on it and go from there.
 

smoke14

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Joined
Feb 22, 2010
Messages
20
Re: Spark Issue on 1970 Johnson 85hp

Thanks F.R. I am waiting on a new distributor cap to arrive tomorrow, found some cracking at the base where it is mounted to the base. After I replace that and reinstall the flywheel I will get those readings while cranking. one question I have is how do you seperate the stator from the old cap? it wont budge, i could destroy the old cap but I dont want to hurt the stator.
 

smoke14

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Joined
Feb 22, 2010
Messages
20
Re: Spark Issue on 1970 Johnson 85hp

Ok finally got the new distributor on - reinstalled everything tried to start for about 5 minutes, about to give in and just as I was letting go of ignition key it fired off and came to life. Shut it down hooked up water, tried to restart had to try several times but finally got it to start, have to release the key for it to start :confused:. Not sure what is causing that but Im thrilled it starts and runs. If anyone has an idea what is going on with the key i will listen to any ideas. Maybe it just needs a new key switch??
 
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