cold spark ?

[michealbugs]

I have been working on this motor forever and can't get ahold of it. I have a 1983 75 hp. 3 cyl.evenrude. I have done almost everything. Carb kit, decarbon comp. check, fresh fuel, plugs. fuel lines and it never runs the same way twice in a row. All the plugs look oily and all are the same. I believe the coils are the OK so I am thinking that either the power pack or the stator is the culprit. I am thinking there isn't hot enough spark to run right. Does anyone out there know how I can check the componets or see it the coils are getting enough juice to work properly?

 

[HighTrim]

Re: cold spark ?

What exactly is it doing, i dont quite understand your post...

 

[Silvertip]

Re: cold spark ?

If you suspect spark is a problem, buy or build a spark tester. Spark needs to jump a 7/16-inch gap with a good solid snap. Anything less than that is weak spark. Since we have no idea what type of operational problem you are experiencing it's difficult to offer advice. You did lots of work to the engine. But did you do it correctly, and was it necessary? Throwing parts at an engine is not good diagnostic practice. It is also very expensive. Did you actually rebuild the carbs or did you just pull the float bowl and clean it out. That's not rebuilding.

 

[michealbugs]

Re: cold spark ?

As I said in my post. It does a little something different everytime I take it out. I am a mech on lawn mowers so I kinda know something about the motor. I think at one time I got some ethenol by accident and the rubber tips on the needle was sticking so I put in a complete carb kit on all the carbs. sometimes it runs good at high rpm and won't idle worth a darn with the idle speeds constantly changing and the last time I took to the lake it idled fine but wouldn't hardly get on plane. It also started acting like it was going to run out of gas several times but about the time you think it was going to completly quit then it would pick up again. It did this several times in 10 mile.
The plugs always look not wet but kinda oily. I know that the power pack and the stator under flywheel supplies juice to the coils and since all 3 plugs are firing the same then I don't thing all three coils would be doing this at the same time. I will try the gap tester on the plug so that ought to tell me something. I am wondering if there is any way you can tell if the volts supplied to the coils from the power pack is hot enough.
I understand that it gets expensive replacing parts. All I have replaced so far is the plugs and 20.00 worth of carb kits. I can't afford to spend a ton and that is why I am trying to read out all I can.

 

[Big Bubba]

Re: cold spark ?

Did you do anything with your fuel pump? It sounds like that could be the culprit. When it does this do you pump the fuel bulb up comming from the fuel tank to see if it stabilizes?

 

[Solittle]

Re: cold spark ?

You can also take squirt bottle with pre-mix in it and squirt some directly into the carbs when the engine acts up. If it smooths out you still have a problem somewhere with the fuel delivery system.

 

[michealbugs]

Re: cold spark ?

the pump bulb still is holding pres during all this.I could see fuel delivery being the problem and I will look into it. I still suspect low spark because of the condition of plugs (oily). I will do something to check fuel presure and the spark gap tester and I'll see what that brings me Thanks