1974 evinrude 85hp wont start

[mike1245]

ok was on the river today boat was perfect then all at once died rad good for about four hours then just stoped it has 120 psi compression and is getting fuel i have a spark tester but have never got it to work on this boat even when it ran great what do you all think and whats the best way to do the spark tester

 

[X-Wrench]

Re: 1974 evinrude 85hp wont start

as far a a spark test, the best and simplest test (just to see if it has spark) is to run a regular spark plug (with a normal ground electrode) and use something to shade it from the surrounding light. i can usually hear the spark as well as see it in lower light conditions. but if you are outside in the sunlight, seeing spark is kind of tough sometimes. a sheet of black construction paper can be used to surround the plug, which will greatly help you see in the direct sunlight. the plug will need to be grounded to see (or hear) a spark. i hope this helps!

 

[emdsapmgr]

Re: 1974 evinrude 85hp wont start

Get an inductive timing light and check each plugwire for spark when cranking. You should see bright, rhythmic flashes from the gun. It will also show misfires, nofires and weak firing.

 

[mike1245]

Re: 1974 evinrude 85hp wont start

ok im getting a timing light in morning but riddle me this as motor turns over i get small amount of smoke out of prop exhaust port but wont start

 

[mike1245]

Re: 1974 evinrude 85hp wont start

used timing light with no light flashes thinking power box that coils are wired to. anyone know of anything else that will make all four coils loose power?

 

[mike1245]

Re: 1974 evinrude 85hp wont start

anyone got any ideas