3.7 mercruiser no spark

[ericcarr2000]

Ok, im at my wits end, I have a 3.7 mercruiser which im having some major problems with. I cant seem to get her started, no spark. Ive taken it in to a marine repair shop, they cant find out whats wrong with it, why im not getting any spark, they did tell me i am getting 12 volts coming out of the coil, but thats where it ends. It has a new distributor in her, a mallory marine distributor. Im just about ready to give up on her.... can anyone out there help on this one????

 

[Don S]

Re: 3.7 mercruiser no spark

If you took your boat to a marine shop and they can't figure out why you don't have spark, then NEVER take a boat there again. They have no buisness being in buisness.
Read this and follow it, and you will find your problem.

http://forums.iboats.com/showthread.php?t=335407

 

[stonyloam]

Re: 3.7 mercruiser no spark

Well the first thing I would do is find out if the points and coil are ok. Take off the distributor cap and rotor. Pull the center wire out of the cap and lay it close to some bare metal on the engine (1/4 inch or so). Bump the engine until the points close. With the ignition switch on, take a screwdriver with an insulated handle and push the points open then let them close. Every time you open the points you should get a spark out of the coil wire. If not you may have bad points, bad coil, or poor ground on the distributor. Once you establish that you can get a spark out of the coil you should be able to figure out the rest. You should have about 9 or so volts at the + terminal (purple wire) on the coil. Let us know how you make out.

 

[Lyle29464]

Re: 3.7 mercruiser no spark

forget this. I was late again. do what don says

any shop could find your problem in minutes if they wanted to.

look under the dist cap and see if your points are opening and closing when you turn the engine over. If they are not set them till they do and clean the contacts. If this it and it tries to run replace them and set them by the book.