85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

[keretty]

I have a 1975, 85 HP Johnson Javelin outboard that was rebuilt using a 115 HP block. I don't know what year it is.

In checking the spark I noticed that when I remove the plug wires from #2,3 and 4 plugs there is a noticable lug in the engine performance (as expected), however when I remove the wire from #1 plug there is no noticable difference in engine performance.

compression is 110 psi
there is good spark
there is fuel
The engine seems to be running well with lots of power.

Any ideas on what is happening here?

 

[jonesg]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

You can't test spark with a sparkplug.
Buy a $12 adjustable gap spark tester from the auto store, set gap to 7/16th inch. Remove all plugs so you get max crank speed.

My guess it will produce a weak yellow spark,
it has to be a fat blue spark or its a fail.
Compare the spark to a good cylinder wire.

Probably coil, swap it to the other side and see if the weak spark follows the bad coil.
Replace.

 

[keretty]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

This is a very confusing problem

I switched out the coil with #2 and #3 coils and the motor wont start.
Next I used an ignition spark tester on each of the plugs with the gap set at 7/16 inches and there was no spark from any opf them.

Next I reduced the gap to 1/4 inch and still no spark off any of them.

After some research I then used an OHM meter and checked the readings on all of the coils and here are the results

Plug # Ground to plug wire Power Pack to Pug wire

#1 56 56
#2 32 30
#3 08 08
#4 10 10

Then I insertted the plugs back in their boots, grounded them to thre motor and confirmed that all the plugs are showing a spark.

With the coils back in the #1 position the boat starts and runs fairly well

I have two spare coils that are metering at 03 and 03 on the ground and powerpack wires. I tried both of these coils in #1 position and the boat wont start. with them installed.

Any help here is appreciated.

 

[Rscardina]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

if you have no spark at all the your kill circuit may be the issue.. have you pulled the red harness plug off and jumped the starter coil to run it?

If you get spark after disconnecting than you'll need to shag down the kill or laynard.

 

[keretty]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

Withe the plugs removed from the engine and grounded to the motor I get a blue spark on all plugs including #1


Could this actually be a reed problem

 

[Rscardina]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

spark on plugs or spark with gap tester?

using spark plugs isnt recomenedd becasue in open air they spark great..but under compression they may not. this is why te 7./16 gap tester is really the tell all..

reed or not? hard to say, usually reads dont fail..or not often.. plus you would ny feel any pulsing from the carb throats either..and you would get fuel spitting backat you ..not a little..a lot.. so I dont think reeds, but you can look down the carb throats and maybe a get a peek without having to rip anything off..maybe?

 

[keretty]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

Based on everything I've read in the last week, since I can't get a spark with the spark tester set at 7/16 inches, it seems that I should be replacing all my coils.

The OHM readings are very different between coils. Any Idea what a healthy coil reading would be?

I'm somewhat confused because the motor will still start and run, and was pushing the boat to about 50 KM/hr.

 

[ezeke]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

If you get spark on all wires with all of the plugs removed you probably do not have an ignition problem but not enough power to your starter when the plugs are in.

Nevertheless, if the ignition sytem checks out and pulling the wire on one of the cylinders with the engine running makes no difference, you have a problem. Check the compression and then cover each carburetor throat one at a time and see which one does not change the operation of the running engine. Clean thaat carburetor.

 

[emdsapmgr]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

Try testing for spark with an inductive timing light when the engine is running under load. See what condition the spark is on all 4 plugwires.

 

[keretty]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

These are all good sugestions.

When I chocked off the #1 cylinder carb the engine lagged a little

I've removed the carborator that feeds the #1 cylinder and cleaned it out. There was no evident of dirt but I confirmed that none of the orfices are pluged and everything appears to be working.

I can see the Reeds and they all apear to be OK. They are in the closed position and when I flex them they return to the closed position.

I have used a timing light and determined that there is spark on all 4 cylinders

Still #1 cylinder has no affect on the engine performance. I can start and run the engine quite well with #1 removed. If I remove any other spark plug the engine will still start but runs extremely rough.

 

[emdsapmgr]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

Any chance that you are getting water into #1? Any milky appearance on the tip of the plug?

 

[keretty]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

No, the spark plug looks identical to the other 3 in appearance.

 

[234rick]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

No, the spark plug looks identical to the other 3 in appearance.

Are you sure that the spark is not jumping to the plug ? Take the plug wire off the coil also & try that. If that plug isn't firing it should be oily black. Not clean with a drak tan ceramic.

 

[keretty]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

Thanks everyone for your suggestions and advice. The problem appears to be corrected.

After I cleaned the carborators I noticed that all my fuel line hose clamps were not tight. I replaced the carb and tightened the hose clamps.

The motor sounds great and when I remove the #1 plug wire the engine lugs as it should. I'm hoping to take it for a test run tommorrow to confirm that the problem is gone and to do some adjustmets .

 

[keretty]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

HELP!

My problem has migrated to #2 and #4 cylinders. Now I have power on #1 and #3 but #2 and #4 cylinders are dead.

 

[keretty]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

This just gets more frustrating every day.

I started to trouble shoot the motor and removed the intake cover to look at the carbs. Then I started the motor to check for fuel. The motor was hard to start but once it fired up it seed to be runnibng better. I removed each plug boot and giot the normal response showing that it was firing on all cylinders.

Then I connected each plug to a spark tester with a 7/16 inch gap, one at a time with the motor running.

Now, all the plugs are firing with a strong blue spark and the motor is running on all four cylinders. This is odd because I didn't do anything to correct the problem.

I don't trust the motor any more because I don't know what was wrong or how it was fixed.

Has anyone else had a similar problem or a suggestion on what causing this condition?

 

[14ftgrumman]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

Possible that you have got a wire shorting out? or maybe a bad ground? It fixed itself by you moving things and connecting and disconnecting things. Keep the canoe paddle handy, or the trolling motor battery charged.

Check for pinched wires or worn thru insulation.

 

[emdsapmgr]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

Weak ignition components tend to fail when they heat up to normal operating temperatures. Possible to work when cold, but may not work when warmed up. Can you trace your problem to whether the engine is just started (cold) or warmed up?

 

[keretty]

Re: 85 HP Johnson javelin - removing the wire froom #1 plug not affecting the engine

I've had two successful runs on the river since I replaced a bad electrical connector on the terminal block.

Hopefully I've located the problem