Johnson 140 Hp No Spark

[JROLL]

New to the forum like to say HI , and now ask for help . I have a Johnson 140 hp belive its a 1984 dont really know much about it still waiting on title. The model # 140843c and serial # j0002615. Engine started when I bought it then went to the lake and was pretty hard to start cranked on it for 3 - 4 minutes off and on would try to bust off but wouldnt catch. Then it just busted off and ran pretty good seemed to have a little miss at idle. Next day back at lake cranks till battery is dead and wont start,I put a screw driver in end of removed plug wire and cranked engine over found no spark at any cylinder. Can any one give me a starting point for diag.....

Thanks

JROLL

 

[HighTrim]

Re: Johnson 140 Hp No Spark

Welcome to iboats. 140843 is the model number for a 1978 Evinrude 140hp

The following may help.

http://forums.iboats.com/showthread.php?t=158071

Although since you have determined that there is no spark present, you may want to look at the following. Scroll down to `Four Cylinder Engines, No Fire At All`. An inline spark tester with the gap set to 7?16 of an inch is the best test. The spark should jump the gap with a bright blue ZAP!!

http://www.boatpartstore.com/page30.asp

 

[JROLL]

Re: Johnson 140 Hp No Spark

Thanks for the help I will check out the fourm you stated and go from there. After reading a little more in the forums It may be low battery voltage causing to slow of r.p.m.s to make spark if I am reading correct. I will charge battery this evening and try it after work ......

Thanks

James

 

[JROLL]

Re: Johnson 140 Hp No Spark

P.S. I guess the engine covers are multi fit , the cover on this engine says johnson on it. I did have a friend look at the motor and stated the coils are in the wrong spot. They are bolted on the top side of the head he stated his are bolted on the side of his heads. He stated this could mean the power head has been replaced with a differnt year or model type not for sure. I bought a 1984 king fisher deck boat and this is the motor that came with it.

Thanks

James

 

[HighTrim]

Re: Johnson 140 Hp No Spark

Thanks for the help I will check out the fourm you stated and go from there. After reading a little more in the forums It may be low battery voltage causing to slow of r.p.m.s to make spark if I am reading correct. I will charge battery this evening and try it after work ......

Thanks

James

that is correct, you will need a good 250 RPM to have the system fire properly. Check the spark with the plugs removed. Let us know what you find.