Rectifier broken; need battery to run engine all day?

[lakefish]

Rectifier not charging starter battery. While waiting for parts can the 40hp nissan electric start outboard run all day without using starter battery (other than to crank) or will starter battery (not being charged while in use but fully charged prior to boat going out) go dead as motor drains the current while running all day?

 

[Todd157k]

Re: Rectifier broken; need battery to run engine all day?

hmmm.. not sure. but if it doesn't, you can always get out and walk home.

 

[lakefish]

Re: Rectifier broken; need battery to run engine all day?

Good suggestion - but last time I did that they wrote about it in what was called a really good book!

 

[lakefish]

Re: Rectifier broken; need battery to run engine all day?

You know I have asked this question to some friends who, like me, have owned many outboards, and all are not really sure of their answers. What simple basic part of understanding of the outboard engine are we missing? Please help - my attempt to walk home is indeed my fear - Thank you

 

[TOHATSU GURU]

Re: Rectifier broken; need battery to run engine all day?

The engine does not consume current while running so the only problem would be with using the electric starter as the day drags on.

 

[Todd157k]

Re: Rectifier broken; need battery to run engine all day?

The engine does not consume current while running so the only problem would be with using the electric starter as the day drags on.

What? Sure it does. What do you think makes the spark? And, the faster you run the motor, the more current used. Then, there's all the 'other' stuff... gauges, trim, lights, etc.

 

[Mr_Shamrock]

Re: Rectifier broken; need battery to run engine all day?

You should be fine. There are many non-electric start motors out there that run without batteries. A good charged battery should be good for a number of starts before needing to be recharged. If you motor doesn't have a pull start on it also I would bring a jump box or an extra battery just to be on the safe side though. I am assuming your motor is not fuel injected.

 

[pvanv]

Re: Rectifier broken; need battery to run engine all day?

What? Sure it does. What do you think makes the spark? And, the faster you run the motor, the more current used. Then, there's all the 'other' stuff... gauges, trim, lights, etc.

As long as it is magneto/cd ignition, it does not require battery for ignition. If it is a TLDI, the ECU does want 12v. What is the model/serial?

 

[TOHATSU GURU]

Re: Rectifier broken; need battery to run engine all day?

What? Sure it does. What do you think makes the spark? And, the faster you run the motor, the more current used. Then, there's all the 'other' stuff... gauges, trim, lights, etc.

You are incorrect. The battery is only used to spin the starter. The rest of the system, on the model in question, is self generating as the flywheel creates the engines voltage in conjunction with the exciter coil.

 

[Barnacle_Bill]

Re: Rectifier broken; need battery to run engine all day?

What? Sure it does. What do you think makes the spark? And, the faster you run the motor, the more current used. Then, there's all the 'other' stuff... gauges, trim, lights, etc.

The stator. But you are correct about the accessories.

 

[lakefish]

Re: Rectifier broken; need battery to run engine all day?

The engine is not a TLDI - it is an older 2 stroke Nissan. I ran the Nissan on the lake today - it ran great. The motor is not charging the starter battery, of course, as the rectifier is not working. The starter battery was fully charged before going out. The motor is apparently providing the spark needed without using the starter battery while running. How does this work? Are there two systems - one to charge the starter battery and one to fire the spark plugs? Now that I know it will run "all day" without the rectifier working, I am trying to understand the parts and systems involved. I do have a pull start on the engine.

 

[pvanv]

Re: Rectifier broken; need battery to run engine all day?

Lakefish,

Yes, the starter system is independent of the rest of the engine. If you wanted to, you could remove it from the motor and (except for arm exercise), all would be as usual. Likewise, after starting, you could disconnect the battery, and the motor would continue to run.

The ignition is magneto-driven... That is, precisely as Elvin noted, the magnets in the flywheel generate power in the exciter as they fly past. Just like a mini power generating station. This system is used in all sorts of small motors, from chain saws, to lawn mowers, to motorcycles... was even used on some dragsters and bracket racers way back when.

The same principle (though on a different circuit, the white and yellow wires) is used to generate battery charging current -- the magnets flying past the alternator coil generates that power. But the battery requires DC, hence the rectifier, to turn alternator AC into battery-charging DC. HTH.

 

[lakefish]

Re: Rectifier broken; need battery to run engine all day?

Thank you all - I am new at posting on this forum, but I have been a follower for some times. I truly respect the quality of the explanations, especially since I have simple engine knowledge only. Thank you again. I now can run my motor with confidence while waiting on parts (rectifier to be installed). I do have a pull start rope, and I have my batteries separated for start and "all else", so I should have a few good electric starts per run without worry and then a rope pull also.