Johnson 83 115hp spark..Help!

[drumman]

On start up this spring I have intermittent spark only on #1 hole? I checked all grounds, wires. Changed coil, power pack, plugs and plug wires?. Under load there is no spark, in my driveway there is sometimes spark? Only on #1 cylinder. When there is no spark and it is running, I can achieve spark by unplugging the stator lead and plugging it back. This will give spark for an indefinite amount of time? I am ready to shoot the engine! I do not believe a faulty stator can cause this only on one cylinder? Any ideas?

 

[ezeke]

Re: Johnson 83 115hp spark..Help!

Your motor needs to turn 300 RPM to fire. Try cleaning your battery cables and use a fully charged, powerful battery.

You test for spark with all of the plugs out so that there is no load and maximum RPM. If you get fire then, you usually have inadequate battery power to turn the engine fast enough.

 

[Joe Reeves]

Re: Johnson 83 115hp spark..Help!

With all of the spark plugs removed, at cranking speed, the spark must jump a 7/16" gap with a strong blue lightning like flame.... a real SNAP! Does it?

Note that the 7/16" gap is important. Do not attempt to test the spark by using the spark plugs as that proves nothing.

(Spark Tester - Home Made)
(J. Reeves)

A spark tester can be made with a piece of 1x4 or 1x6, drive a few finishing nails through it, then bend the pointed ends at a right angle. You can then adjust the gap by simply twisting the nail(s). Solder a spark plug wire to one which you can connect to the spark plug boots, and a ground wire of some kind to the other to connect to the powerhead somewhere. Use small alligator clips on the other end of the wires to connect to ground and to the spark plug connector that exists inside of the rubber plug boot.

Using the above, one could easily build a spark tester whereas they could connect 2, 4, 6, or 8 cylinders all at one time. The ground nail being straight up, the others being bent, aimed at the ground nail. A typical 4 cylinder tester follows:


..........X1..........X2

.................X..(grd)

..........X3..........X4

Spark plugs should be Champion QL77JC4 plugs, gapped at .040 . Are they?

Check the stator for the proper ohm reading as per your service manual.

If at the proper cranking rpm as Zeke states above, the spark is weak, visually inspect the stator. If it is cracked and/or oozing a sticky looking substance down on the powerhead, replace it regardless of what reading you may obtain.

 

[drumman]

Re: Johnson 83 115hp spark..Help!

Thanks for the reply's....The batteries are new, the plugs are stainless NGK br7hs Gapped at .40 Remember this spark is intermittent on cylinder #1 ONLY...Could a bad ignition switch do this? This is freaking me out?

 

[tashasdaddy]

Re: Johnson 83 115hp spark..Help!

you should be running Champion Plugs. 115 1979 - 1998 QL77JC4 or QL82C gapped .030. running other brands has been known to cause misfiring problems. also could be bad plug wire.

 

[drumman]

Re: Johnson 83 115hp spark..Help!

Well,,,NGK makes a good plug. However, It is the only thing I have not checked other than moving them around. I understand the gap to be .040 not .030? It is not the plug wire as I have moved them around too. I will put the old plugs back in which worked fine last year. If that cures this, I will eat my shorts!

 

[npd4432]

Re: Johnson 83 115hp spark..Help!

I always thought the plug gap for my motor E75TRLCTE with the QL's was .030 for alot of WOT operation and .040 for alot of trolling. What is the proper gap??

 

[Joe Reeves]

Re: Johnson 83 115hp spark..Help!

Yes, I'm aware that your spark problem applies only to #1 cylinder. It's possible that the other 3 cylinders are firing with the weak spark if weak ignition does exist, hence my suggestions in detail...... and the plug gap is .040. I'm aware that many years later a bulletin was issued changing the gap to .030.... I happen to disagree with it.

 

[drumman]

Re: Johnson 83 115hp spark..Help!

Well... changed the plugs back to Champion, water tested, no change.
Did a full Diagnostic, per the repair manual, on the ignition system. Checks out perfectly....Water tested again, no spark on #1 cylinder. Out of ideas! works out of water but not in water?

 

[CharlieB]

Re: Johnson 83 115hp spark..Help!

A possible clue is that you mentioned it works after unplugging the stator from the module then replugging it back in.

Is it possible that you have a 'loose' terminal within one of those sockets?

Maybe even a broken wire at the other end of one of those terminals?

You can fabricate a small tool to 'push' these terminals out of the boots/socket for careful inspection then just as carefully reinstall them, CAREFUL to return each to their respective position!!!!!

 

[CharlieB]

Re: Johnson 83 115hp spark..Help!

Oh, the Champion vs NGK thing

I have run into 2 j/e's that did NOT run well with NGK's and those I did install the much more expensive Champions.

I can't count the number that are out there running NGK's BPR8HS at 032 perfectly. (BPR7HS if the compression is below 120)

BE SURE that the temp sensor wires are WELL AWAY from all plug wires.

 

[drumman]

Re: Johnson 83 115hp spark..Help!

first. I would like to thank everyone for your help.

It is not the stator wire or any other wire. It does the same thing when I unplug and plug the Timer base??? I have tested every wire on this engine.

It is also not the spark plugs. So, I have to either kill my boat or figure it is some solid state malfuntion in either the stator or timing base. Maybe there is a rat living in hole #1??? either way... I am burnt! The Japanese knew something...r-

 

[ezeke]

Re: Johnson 83 115hp spark..Help!

Did you swap the ignition coils and power packs to see if the problem followed?

 

[drumman]

Re: Johnson 83 115hp spark..Help!

yes