regulator/rectifier function

[kylewalker]

Exactly how can a bad regulator rectifier cause a no spark on any cylinder condition?

[j_martin]

Welcome,
I know that Scream n fly's crowd has a tremendous reputation for being genuinely genius, but I don't think any of them are clairvoyant, thus they need to know what motor you are working on.

[kylewalker]

Welcome,
I know that Scream n fly's crowd has a tremendous reputation for being genuinely genius, but I don't think any of them are clairvoyant, thus they need to know what motor you are working on.

This is a general question. A bad regulator/rectifier can cause a no spark condition on many years and makes.

How? Aren't the wingdings for the charging circuit different than the ones that go to the switch boxe(s), or cdm(s).

So how can it take out spark?

[keefallan]

I haven't looked at a schematic of outboard's electrical systems to answer fully. But if a rectifier is in charge of converting ac to dc, and it stops working, then will the ignition system run on ac power? probably not.......not if it needs dc to operate. Like I said, I cant really answer fully. This is an electrician's educated guess with knowing what a rectifier does and how it could effect the ignition.

[Capt.Insane-o]

[keefallan]

now thats a fire!!!

[BOATMANBLUES]

the battery charge windings,the charge coils for the paks, the accesory coil if it has one are all independant circuts in the stator...main winding is ac voltage to the rectifier which converts it to dc ...charge and accesory coils are ac to the paks etc ....so in theory a bad rectifier should not cause a no fire situation in the ignition ...I have had several no fire that I tracked down to a bad rectifier though....usually if you unplug it from the stator the motor will then fire...so my guess has always been that the grounded rectifier heats up the main frame to the point that the charge coils overheat and stop producing enough voltage to charge up the capacitors in the paks...or....the grounded rectifier draws so much amperage that the starter won't spin fast enough to fire up the motor....I have fired up a motor with the bad rectifier unplugged,then plugged back in and the motor stayed running....wouldn't fire back up with it plugged in....so thats my SWAG.....scientific wild ass guess

[keefallan]

I would not have thought ac power to the packs..........learned sumthin today.

[kylewalker]

for sure. That is why you have to measure DVA at the pack.

[j_martin]

I like the SWAG system of engineering. Quality control, then, is TLAR (That Looks About Right) BTW, that is how Dick and Burt Ruten describe the creation of the Voyager, the first airplane to fly non stop around the world.

Electrically, a dead short across the power winding in a stator could saturate the core (magnetically) and that would limit the peak voltage available on other coils, the CD charge coil, for instance. That would kill a marginal ignition system.

[Motv18]

Could iirc are dc the ac cycle would cause spark every time the field collapsed and switched polarity. I.e. humming like a transformer on a power pole.

Regulator normally uses a exciter wire to control voltage to the electro magnetic field to regulate output voltage. Iirc main difference between generator and alternator was permanent magnets vs electric magnets more or less today it’s application. Stator is just a fancy generator with flywheel as the armature

rectifier is mainly just a pack of diodes and some add capacitors to produce smoother flow. No capacitor wave form -_-_- ok that’s bad where capacitors make it ~~~~ more level.

It can screw up spark spark due to branch circuits running dc that control the spark and such. Like wrong voltage or polarity on the kill circuit

[j_martin]

The main design difference, from a practical point of view, is that the rotor, be it wound or permanent magnet, can run at a much higher speed than a DC generator. With that, it can be designed to provide adequate current at idle while having a limited amount of iron in the magnetics so it saturates and limits the current output, protecting the windings, without any control at all. A 20 amp stator coil on a Mercury running at 5000 rpm will put out about 21 amps into a dead short, and 19 or so at 75V. The 2 20 amp coils in a 40 amp stator, wired in series, will fully power 2000 watts of 120V lighting at 4000 rpm. (I've done it)

There's a ton of things that can be done with all that. The systems on boat motors are pretty primitive.