Bad Stator 75 horse Mariner

[starkyb]

What are the symtoms of a bad stator. Had carbs rebuilt, fuel pump replaced, new plugs, fresh gas and all new fuel lines but the motor won't idle and of get to full power at wot. It is a 1988 3 cylinder. Also did a compression test and all 3 check out ok and have spark on all 3 plugs. Any help would be greatly appreciated.

 

[JDusza]

Re: Bad Stator 75 horse Mariner

Bad stator will not send enough voltage to the coil. The coil will try to boost what it has been sent, but if it hasn't been sent enough the coil will not fire with enough. A bad stator will give you either no spark or low spark.
Check CDI Electronics | Outboard Motor Parts | Ignitions | Marine Engine Diagnostic System | Stators | Ignition Packs | Regulators | Coils | Wiring Harnesses for their troubleshooting guide. It'll get you to the right components. You'll need a DVM with peak hold and a DVA (voltage divider).
Or using an air gap spark tester, set the gap to 3/8 - 7/16"". If you can jump that air gap, you're all set in the spark energy department and you'd have to look at fuel delivery.
Sounds like you have carb trouble; low speed circuit blocked. What was done at carb rebuild?
J

p.s., do not throw money at the stator or triggers or packs. Those parts are so expensive that it'll pay to get a DVA (about $25) for your peak hold multimeter. That could save you hundreds $$$ on a stator or trigger. And, a the end, you'll be a pro and can service all your friends ignition problems!!!

 

[starkyb]

Re: Bad Stator 75 horse Mariner

The floats were set to specs because they were flooding out. He cleaned them put new gaskets on them. What blocks the low speed circuit?

 

[JDusza]

Re: Bad Stator 75 horse Mariner

Junk in the gas, crumbs going through. Old gas will varnish and block the jets. Gotta actually go in and clean the jets with a tool. A cleaning and new gaskets will not catch this. You have to flip the throttle butterfly open and stick a wire in the jet to clear it. Or depending on the carb, remove the welch plug, clear the jets and replace the welch plug. Not sure if your carb has welch plugs.

Looks like you can access the stuff to clean by removing a cover? I've never worked on one of these before...

 

[starkyb]

Re: Bad Stator 75 horse Mariner

Do the carbs need to be removed?

 

[JDusza]

Re: Bad Stator 75 horse Mariner

Best if they are. Get new intake gaskets, right?
I'm not that familiar with the set-up, but the parts list shows covers on the tops of the carbs. It may be too cramped to reliably work on them attached. I'd take them out.