Not getting fire to plugs on Mercruiser 170

[stuffer]

I just can't figure this one out. I am getting fire to the points but not to the plugs.

I have installed new coil, and condenser. After cleaning out carb of old bad gas it fired up for about 15 seconds and stopped. cleaned it out again but still won't start.

If I an getting fire at the points, I should be getting fire to the plugs. Even tried grounding out a new plug against the engine block but no spart at the electrode.

Any ideas on this, I am really stuck.

 

[dlvwill]

If you are getting spark through the points then the next step is the coil. Make sure you are getting 12V to the positive side of coil with key on. Also make sure that the wire between the negative coil post and the points isn't grounded somewhere along the way. A common place is where it bolts to the points with the eyelet touching the base plate.

 

[sweet revenge]

firs pull the center cable from the distributor cap and place it close to ground, crank the engine and check for spark. if you have spark coming from that cable that means the coil and points are good. your problem is either the rotor button or the distributor cap. if you are not getting spark check the points first, if you have the cap removed you can actually see the spark at the point contact. if nothing is happening make sure there isn't any grease at the point contact, if all is okay, check positive voltage at coil and at the points. remeber the points causes a short to ground and thats what fires the coil. good luck not to hard to check.
mike sweet revenge

 

[stuffer]

Thanks, I will be checking this out this evening and let you know

 

[stuffer]

Thanks for getting back to me on this. I will be working on it again this evening and let you know what happens.

 

[sweet revenge]

let me know how it goes

 

[stuffer]

Still not starting. When I turn the engine over and look at the points there is no spark at the points. I have noticed there is continuity between the coil plus side to the ground. This don't seem right. I am checking tonight to see if the tach may be shorted out and also the slave solenoid. The points are clean and look fine. The battery is new. The coil is brand new. There is just something I have overlooked. I am off work tomorrow and will spend the whole day working on this.

 

[jitts3]

You wont see spark at the points. Did you adjust them? Do you know how. If you don't have a feeler gage then use a matchbook cover. That is the old trick. Turn the engine till the points are held open by one of the 4 bumps in the distributor. Adjust the points till the matchbook slides through the contacts with some pressure. I would clean the points first with fine sandpaper of emery cloth. Doesn't take much to stop the flow of juice. Check your wireing as the others have suggested, but if you are waiting for spark at the points, you will wait for water to no longer be wet.

 

[stuffer]

Was late last night when I finished so I will check on this today. I have cleaned and sanded the points and set with feeler gauge. I am not going to let this beat me. This is a simple engine, the kind I grew up with. So this is what is frustrating to me.

Thanks for the info, I can use all the help I can get on this one.

 

[Woody]

You wont see spark at the points. Did you adjust them? Do you know how. If you don't have a feeler gage then use a matchbook cover. That is the old trick. Turn the engine till the points are held open by one of the 4 bumps in the distributor. Adjust the points till the matchbook slides through the contacts with some pressure. I would clean the points first with fine sandpaper of emery cloth. Doesn't take much to stop the flow of juice. Check your wireing as the others have suggested, but if you are waiting for spark at the points, you will wait for water to no longer be wet.

I don't think I've seen points that didn't arc. The arcing is the primary cause of eroded points:huh:

 

[annie]

Have you remembered to refit the rotor? It's a longshot but I have done this myself.

 

[stuffer]

Mike, Thanks for the info. I am not sure what you mean by "refit the rotor". If you meant, did I put it back in before trying to start it I did.

As of tonight, I feel that I have a short somewhere, I am going to try and find it in the morning, it is just too hot outside right now (104 degrees).

 

[stuffer]

OK, it has finally started. I went down to my local parts store and bought a new set of points, although the old ones looked just fine. I installed, and set the gap put it all back together and it fired up on the first turn of the key. While it is running rough, I am sure when I get it on the lake and check the timming, the dwell, and adjust the carb and run some of the dust off it, it should be just fine.

I want to thank all that contributed to my post.