3.0l 1989 mercruiser loosing spark

[PvH]

Hi i have a 3.0 mercruiser starts idels smooth.. I replaced my cap rotor and points, also have new coil. problem is when i get on plane after about five minutes or so it dies right out, like some one hit a kill switch. when i pull a plug wire to test for spark there is nothing untill i pull the cap and ark the points a few times with a screw driver. once this is done i get spark again and it runs fine again for awhile, sometimes it will run for an hr before this happens other times two minutes.. ive tried removing tach/grey wire from coil with no results...

 

[dubs283]

Re: 3.0l 1989 mercruiser loosing spark

when you installed the new points did you set dwell/timing??

 

[PvH]

Re: 3.0l 1989 mercruiser loosing spark

yes set timing it will not shut down under 2000 rpm

 

[Don S]

Re: 3.0l 1989 mercruiser loosing spark

Did you replace the condenser?

 

[PvH]

Re: 3.0l 1989 mercruiser loosing spark

yes condeser was replaced it only shuts down at rpm higher than 2000 its loosing spark somewhere then wont have any untill i bunp the points with screw driver then it has all spark back

 

[Don S]

Re: 3.0l 1989 mercruiser loosing spark

Moving the points doesn't make sense. Check the distributor shaft bushing for wear. It will only move in one spot, so check all directions. You may have to pull the distributor out to check it.