66 Johnson No Spark HELP

[kellyj]

I just recently purchased a boat from a guy. The boat has a 1966 Johnson Seahorse V4S 80HP. When I bought the boat the guy told me the engine had no spark but the compression was good and the motor was good mechanically. He told me that it had sat for the winter and when he went to start it in spring no go. He also told me he was screwing about with the ignition wiring (sound familiar to an ad posted here a fwe days ago). Anyway I've done some tracing and here's what I found.<br /><br />Starting at the ignition switch :<br /><br />The Batt Terminal has +12v feed from the battery<br />The A Terminal has +12v when the key is on.<br />The S terminal goes to the solenoid which feeds the starter<br />There are two M terminals - one goes to ground while the other goes to the terminal which feeds the points from the coil.<br /><br />There is an electrical box at the back of the boat which houses the solenoid for the starter. One side of the solnoid is connected to the battery while the output feeds the starter. The two control terminals on the solenoid : One goes to the 'S' terminal on the ignition switch while the other goes to a safety switch. The safety switch I was told was broken so it has been removed and the wire is taped up going nowhere. <br />When I turn the key over the starter is cranking over good. I am assuming that the safety switch is so that the engine cannot be started when the engine throttle is set high. I assume the this switch will ground this terminal therefore not allowing the starter to crank when the throttle is high. (is this correct in my thinking??) I am assuming this switch is not the cause of my no spark problem but correct me if I am wrong.<br /><br />The wire that comes from the 'M" terminal is connected to the coil and the points. The other side of the coil is connected to ground. I measured the voltage on the output of the coil which directly feeds the rotor and I am only getting ~40v ac there when I am turning the engin e over. I am assuming that this coil is bad as everything else seems to check out ok. <br /><br />I am assuming that the voltage created to fire the plugs is solely created by the electromagnetic field created by the flywheel spinning belt feed. When the key is then turned off the M terminal connected to the output of the coil feeding the points is connected to the other M terminal which is ground - this cuts the ignition process.<br /><br />I am right here in my thinking??

 

[R.Johnson]

Re: 66 Johnson No Spark HELP

Your engine has a 12 volt battery ignition system. If the engine has been sitting idle for some time the point's could well be oxidized, and simply not making contact, just try cleaning them first.

 

[kellyj]

Re: 66 Johnson No Spark HELP

I already cleaned the points. I set them to 0.020 bacuse one was a bit off. What do you mean by 12volt battery ignition system?

 

[phatmanmike]

Re: 66 Johnson No Spark HELP

means your motor runs from a 12volt battery, as apposed to a magneto style ignition that makes its own electricity, your ignition needs a battery and has a amplifier to make more juice

 

[kellyj]

Re: 66 Johnson No Spark HELP

There is only two wires (other than the starter feed) going to the motor. One wire is black and the other white. The black wire is connected to a terminal where the coil and the wire feeding the points are connected. The other wire (white) goes to the kill switch which is missing right now. There does not seem to be any 12V from the battery feeding the coil. Should there be? Looks like the white wire going to the kill switch has 12v on it but it's not going anywhere. I was under the assumption the the voltage created by the magent/iron was the feed for th ecoil/points is hti swrong?

 

[kellyj]

Re: 66 Johnson No Spark HELP

As an aside . . when I went to look at the parts manual at the local boat shop to see how much the coil was, the ignition system that was on my motor did not mathc up with what was in the 66 manual but rather was the style of a 64 engine. Not sure if that helps. The shaft going up to the points and down to the rotor has iron around it while the casing is magnetic. Next to this is the coil I was speaking up which I think pick up the electricity created inductively.

 

[R.Johnson]

Re: 66 Johnson No Spark HELP

You have me lost here, is there a coil mounted outside of that distributor? The white wire goes to the srarter safety switch, it has nothing to do with the ignition.

 

[kellyj]

Re: 66 Johnson No Spark HELP

Excuse me (actually corrrect me so I know next time) if I am using bad terminology here in my descriptions. There is a black case underneath the "wheel" housing the points. In that case there is a shaft. This shaft at the top open and closes the points. At the bottom there is the 'rotor' which spins around touching each one of the four nipples which are are connected through the wires to the plugs. Approx half way up this shaft (in the middle) there is a huge piece of iron (i think that is what it is) and the black case surrounded this is magnetic. So i think the proper term for this magneto. Directly beside this in the same black case is a coil with two wires and a metal contact on the bottom. THis coil also has iron sticking out both sides so I am assuming that this coil is picking up the elctromagnetic field created by the spinning of the magneto directly beside it. One of the coil wires is grounded to the case while the other goes outside of the case via a screw (this screw is insulated through the case so is not making contact with chassis gnd) and feeds the points. The metal noce on this coil makes contact with a conductive spring on the bottom of the distributor which a conductive strip in it going to a brush and spring in the center. This conductive brush and spring touches the rotor which distributes the spark. I do not believe this is the original head from this unit (or so I'm told). <br /><br />So what I believe I have is a magneto style ignition system. The two wires coming from the inside of the boat and for a safety switch and an engine kill when the key is turned off.<br /><br />Now to my tests. I definitly do not have spark at any of the four plugs. I have taken the plugs out inspected them, cleaned them, and put them back . .they looked good. I cleaned the points and reset them to 0.02 so they are now ok. I took the metal tip output of the coil and connected if up to a spark gap measuring tool which the other end connects to gnd - no spark. I then measured the output of this coil using a voltmeter and was getting approx 40Volts AC. Should the output of this coil be ac or dc?? Anyway, my logic is pointing me to the coil being bad.<br /><br />Any input would be greatly appreciated!<br /><br />Thanks<br /><br />James

 

[OBJ]

Re: 66 Johnson No Spark HELP

James....the points shoulf be set at .010. <br /><br /><br />Please post a model number so we can determine if your engine is a 66' or different year.

 

[kellyj]

Re: 66 Johnson No Spark HELP

The Model Stamp on it says V4S-18C. There is a stamp in the metal that cover the points that say "Set points to 0.020" - that's where I came up with the number.

 

[OBJ]

Re: 66 Johnson No Spark HELP

OK....66' it is. Go with what is stamped on the plate for point setting. A few of the later models used .010. Sorry if I confused you. I'm on my way to the shop in a few. Let me take a look at some service literature and maybe give you some ideas. These old horses can be a pain sometimes to get spark from.

 

[kellyj]

Re: 66 Johnson No Spark HELP

Thanks for the help! One more quick question regarding magneto . . . there is a volage created by spinning the iron core around inside of the magnetic casing . . . perhaps I am looking at this wrong. Is the voltage created present on the shaft going upto the points?? I beleive this shaft when measured was 0 Ohms to the case . . . is there supposed to be some kind of isolation between the shaft and the case containg the points?

 

[rickdb1boat]

Re: 66 Johnson No Spark HELP

I believe that .020 is the correct setting for the points. OBJ will confirm later...

 

[Joe Reeves]

Re: 66 Johnson No Spark HELP

Kelly.... From what you've had to say, I can only assume that someone has removed the automotive type ignition and distributor setup, then installed one of the older style magnetos.<br /><br />If so (magneto), the plug wires would be coming out of the distributor cap at the bottom of the magneto, pointed straight down, then leading to the s/plugs. If so, yes, the points do set to .020.<br /><br />Have the ignition key in the ON position when spinning the magneto drive wheel as mentioned below.<br /><br />Remove the distributor cap, then connect a wire directly to the high tension coil terminal. Rig that wire so that a 1/4" gap exists between it and the block (ground). Spin the magneto drive wheel. If you now have spark, you more than likely have a faulty rotor.<br /><br />If still no spark, disconnect the wire that leads from the magneto to the ignition switch to eliminate a possible wiring short or faulty ignition switch problem.<br /><br />Let us know what you find.

 

[kellyj]

Re: 66 Johnson No Spark HELP

I did similar already to what you suggested here. What I did was hook up a test tool that allows you to see how far of a gap a spark will jump across (it is settable). One end of this hooks up to grond while the other end I hooked up to the output terminal of the coil. I had my wife start cranking the boat over and did not see a spark here. I checked the wire going to the 'M' terminal of the ignition and found that there is approx 4Meg Ohms between it and ground when the key is on which rules that out. I then placed a voltmeter on the output node of the coil and once again had my wife crank the motor over . . I was reading about 40V ac . . . I should see a spike on here when the points open (maybe I just couldn't see it with a meter (probably need an oscilloscope for this. Any other thoughts?

 

[OBJ]

Re: 66 Johnson No Spark HELP

Maybe Joe Reeves can straighten me out here.....Wasn't there two different ignition systems for this engine? There was the "Speedifour" and "Starflite" and I thought one had the magneto system....the thing hung over the back end of the engine block and the other was under the flywheel. I dunno...maybe I'm out in left field. :-O

 

[kellyj]

Re: 66 Johnson No Spark HELP

My system (magneto) runs off a rubber belt which runs to the flywheel). The cover housing the points (which has the shaft running down to the rotor .. etc) has teeth on it for the belt to connect back to the flywheel via said rubber belt. I have some jpegs i can send if you give me your e-mail address. I appreciate all the help you have given so far! I am new to the boat scene (this is my first boat actually). I have some samll engine experience working on lawn mowers and such but have never touched an outboard motor before . . . still learning. Anyway . .thanks for your patience!

 

[Joe Reeves]

Re: 66 Johnson No Spark HELP

OBJ.... The ignition setup under the flywheel came into existence in 1968.

 

[hitnrun1975]

Re: 66 Johnson No Spark HELP

I have a 1965 60hr sea hores and had the same problem last year I got sick of messing with it and put and external coil on it. I tried a new coil at $70 and that didnt work so I think the problem is in the magneto and good luck finding one of those. If you want to know how I hooked up the external coil and what kind I used I woul be happy to email you directions and pics Jon

 

[kellyj]

Re: 66 Johnson No Spark HELP

hitnrun . .send me the info please. I have already gone ahead and ordered a coil now (similar to what you did) If it's not that the looks like it may be th emagneto . . don't really understand what can go wrong with a magnet and a piece of iron . . you can e-mail me at James_Kelly (at) Mac.Com