merc 4 cyl 3.0 140hp wont start no spark

[clyner]

hey guys, got to the launch today an it wouldnt start, 2 weeks ago she ran fine. last nite i left ignition on an got a dead batt. i put a new one in there. so i pulled two plugs and neither had spark, but she turns over. just keeps turning an gets nothing. i checked the coil both sides + an - have +10-12 volts. not sure what to do from here dont have a manual and its gonna be 90 tomorrow one of the last good days this year any ideas?????????????

 

[Adirondack]

Re: merc 4 cyl 3.0 140hp wont start no spark

Take your test light connect it to a good ground, and hold on the negative side of the coil. crank the motor. If it doesn't flash replace your points. leaving an ignition on for a long period of time can sometimes damage them.

 

[Adirondack]

Re: merc 4 cyl 3.0 140hp wont start no spark

While your there also make sure that you have 12v to the positive side of the coil while your cranking the motor.

 

[wrnutsdad]

Re: merc 4 cyl 3.0 140hp wont start no spark

Shot in the dark, but in the really old days if you left the key on and the points were closed they could actually heat up enough to semi weld themselves together. First time it cranked over would distort the point contact alignment, results ...no start !!! Try explaining that to your dates father !! Seriously check points ....pull off dist. cap ...are points closed ? If not rotate engine untill they are ... are they lined up nice and pretty ??? If so take standard screwdriver and go between movable contact and shaft ...turn key to on position ....twist screw driver making the two point contacts to separate..... you should see a small spark at point contacts and if you hold coil wire coming from coil to dist. cap close to a ground it should also spark when you separate the points. No spark ....you probably fried the coil..check with multimeter....good luck !!!

 

[clyner]

Re: merc 4 cyl 3.0 140hp wont start no spark

i hear there chevy motors, if i goto autozone what kind of motor would i tell them that i need parts are for

 

[Don S]

Re: merc 4 cyl 3.0 140hp wont start no spark

Tell them you have a Mercruiser 4 cylinder engine 140 and tell them the year. They will be able to look it up.

 

[clyner]

Re: merc 4 cyl 3.0 140hp wont start no spark

was the points, an reset timing.. took to marina $80 done in 3 hours

 

[Adirondack]

Re: merc 4 cyl 3.0 140hp wont start no spark

was the points, an reset timing.. took to marina $80 done in 3 hours

Happy boating!