1975 Johnson

[johnson75]

hey i just bought a 1975 johnson 115 and it has no spark and i have no clue where to start on a boat i have never missed with them before if anyone know any thing will you plz. let me know.
thanks

 

[ezeke]

Re: 1975 Johnson

The CD ignition requires 300 RPM to generate healthy spark, so you will need a powerful, fully charged battery.

Test for spark with all of the spark plugs removed, using a tester that can be set for at least a 3/8 gap. You should see a strong snappy blue spark.

 

[johnson75]

Re: 1975 Johnson

hey i got the batt. all charged up and check the spark and still have nothing so if u have any other ides yet me know thanks

 

[Solittle]

Re: 1975 Johnson

You said "i have no clue where to start on a boat" - - my advice for you is to find a good marine mechanic and pay the man. There are a whole bunch of things you need to do to the new to you engine in addition to finding spark - like compression, water pump, thermostats, gear oil, plugs, sync & link, timing - got your attention? They are way beyond the scope of the advice you will find here. You could start by getting a manual and reading your brains out.

 

[johnson75]

Re: 1975 Johnson

thanks but no thank i will find it i was just asking someone where to start thanks

 

[crb478]

Re: 1975 Johnson

hey i just bought a 1975 johnson 115 and it has no spark and i have no clue where to start on a boat i have never missed with them before if anyone know any thing will you plz. let me know.
thanks

First assure that the motor is spinning over fast enough, even with a good battery the cables can be shot and you will not get enough vlotage to spin the motor. Feel you cables to see if they are getting hot. Then do a compression test, there is no reason to chase down the electronics if the motor is not mechanically sound. Look for over 100 psi with all cylinders within 10 percent of each other.

Then check for spark on all cylinders while the motor is spinning 300rpm or more. Clean all of your grounds from the power pack and coils until they are shiny, and make sure your ground straps are in good shape as well.

To do any more than this a oem manual would be very beneficial, but there are some online ignition test that can also work.

Your problem can be anyting from your grounds, power pack, ignition coils, charge coils, stator, or timer base.

 

[johnson75]

Re: 1975 Johnson

Thanks i will do all of that and see what i come up with.

 

[CARDNAL98]

Re: 1975 Johnson

If You Are Not Getting Spark On Moptor Before You Spend Lots Of Cash You Have A Bad Triger If You Look At Power Pack You Will See The 2 Wires That Come Out From Under Flywheel And Connect To Your Power Pack Then Power Pack Sends Spark To All Cylinders. To Repair Triger You Must Remove Flywheel First. Whem You Remove Flywheel You Will See The Stator That Is What Charges Your Battery The Triger Is Under Stator And It Has 2 Or 3 Sensors On It Those Are The Sensors That Make The Spark That Gose To Your Power Pack And Cylinders. Being And Older Outboard Boat Shop Wont Have The Sensors What You Can Do Is Look On Ebay For A Good Used Triger If There Is No Triger Like The One On Your Outboard Look For One That Has The Same Sensors You Can Replase Them With Your Bad Ones The Bolt On Very Easy Fix. Before You Buy New Triger Clean Your Sensors On Your Triger And Try To See If You Get Spark If You Do Not Get Spark Push Them In Closer To Your Flywheel They Could Be Worn And Not Makeing Good Contact. Hope This Will Help You .

 

[ezeke]

Re: 1975 Johnson

If You Are Not Getting Spark On Moptor Before You Spend Lots Of Cash You Have A Bad Triger If You Look At Power Pack You Will See The 2 Wires That Come Out From Under Flywheel And Connect To Your Power Pack Then Power Pack Sends Spark To All Cylinders. To Repair Triger You Must Remove Flywheel First. Whem You Remove Flywheel You Will See The Stator That Is What Charges Your Battery The Triger Is Under Stator And It Has 2 Or 3 Sensors On It Those Are The Sensors That Make The Spark That Gose To Your Power Pack And Cylinders. Being And Older Outboard Boat Shop Wont Have The Sensors What You Can Do Is Look On Ebay For A Good Used Triger If There Is No Triger Like The One On Your Outboard Look For One That Has The Same Sensors You Can Replase Them With Your Bad Ones The Bolt On Very Easy Fix. Before You Buy New Triger Clean Your Sensors On Your Triger And Try To See If You Get Spark If You Do Not Get Spark Push Them In Closer To Your Flywheel They Could Be Worn And Not Makeing Good Contact. Hope This Will Help You .

Timer base is readily available - OEM and aftermarket.

http://www.iboats.com/mall/partfind...d_poid=334642&gd_row=163&**********=483601839



Wiring to the 1975 V4 powerpack is not as described above.

Parts replacement without proper troubleshooting first is an expensive mistake.

Most ignition parts are manufactured by a few companies like CDI Electronics, whose Troubleshooting Guide is free for download on line.

http://cdielectronics.com/downloads/troubleshooting guide

 

[johnson75]

Re: 1975 Johnson

i got a johnson 115 and i got good spark and fuel and i had it running about 1 week ago and it sat in the shead and went to get it out and no start but it gots good fire and fuel and still no start i need some thoughts thanks

 

[emdsapmgr]

Re: 1975 Johnson

If you want to look into repairing your engine yourself, you should get an original factory service manual. It is excellent for showing how to diagnose and repair the engine. You can get one from the original publisher, Ken Cook Co., in Milwaukee. They are also on th web.