Electrical problems causing stall?

[mooseo]

Re: Electrical problems causing stall?

Ok, spent some time playing with the motor this weekend with some friends who know more about motors (at least car motors) than I do.<br /><br />Tested the stator coils with a really high-end digital multimeter... unfortunately, I'm not entirely sure I was using it right on the peak voltages. I checked the resistance, then checked the peak voltages just turning it over for a couple of seconds.<br /><br />Yellow wires: 0.17 ohms. peak voltage 300milivolts<br />Brn wires: 1043 ohms. peak voltage 12.2 volts<br />org wires: 52.8 ohms. peak voltage 1 volt<br /><br />these numbers seem really weird. I have the chart from Outboardparts.com which indicates that my resistances are exactly right, but these voltages are screwy. Should it be putting out the right voltage on just a quick crank? I can try to find a meter that I can understand and try again. Does it make sense that it would have the right resistance, but then not work when turning?<br /><br />I did get the motor started and running for a few minutes. The timing seems badly off (which it wasn't when these problems first started)... lots of misfires. Doesn't seem to have any charging voltage and the tach bounces around but mostly reads zero. Anyway, it still seems like I am looking at the same basic problem of stator / rectifier-regulator. Not sure which to replace first.

 

[clanton]

Re: Electrical problems causing stall?

I dont think your meter is reading peak volts.

 

[mooseo]

Re: Electrical problems causing stall?

Ok, I borrowed a better meter (i.e. one that I can understand). Measured peak volts at 1ms sampling interval on the stator coils, turning motor over very briefly.<br /><br />Yellow wires: 7.2-7.4 volts<br />Orange wires: ~50 volts<br />Brown wires: 250-300 volts<br /><br />Those are definitely different from what you told me above, but not as hopelessly wrong as my previous ones. <br /><br />What do these numbers suggest to anyone? Is my stator bad, or should I still suspect the rectifier (or both)?<br /><br />Thanks,<br />mike

 

[seahorse5]

Re: Electrical problems causing stall?

If your motor has the pan mounted trim switch on the starboard side, you have the 90 degree motor. When you remove the motor cover you will see the flywheel on top of the motor.<br /><br />The 60 degree engine has the trim switch on the port side and the flywheel is hidden under the plastic covers.<br /><br />If you have the 90 degree, which I think you do, the regulator/rectifier is around $75. Your readings are in the ball park for the stator. If you have wing nuts on the battery, remove them, polish the cable ends and terminals, and use lockwashers and stainless steel nuts to fasten them. Loose, corroded, or intermittent connections in the battery circuit are what damages regulators.<br /><br />Are there any cracks or melted areas on the stator? The only way a stator would kill the motor is if the charge coil (brown wires) shorted or opened up. On that motor, it is more common to have the power pack temporarily fail at the most in oportune time.

 

[almost retired again]

Re: Electrical problems causing stall?

Good readings on the brown wires,(charge coils), good readings on the orange wires (power coils),seems low on the yellow & yellow/grey wires, but that could be caused bt slow cranking speed. The faster the magnets turn the more voltage that is produced. Can you read this voltage with the engine running? Basically there is only two things that can happen to any electrical circuit it can open(max resistance), or it can short (zero resistance) which usually causes blown fuses, melted insulation, or max smoke. However you can have partially open or part partially shorted circuit and if so you have to go by mfg. spects. If a circuit is open it's not putting out any current, but will still produce a voltage ( that pressure that pushes the current) so after all of this I don't think that it will hurt anything to disconnect the stator output and read the voltage.<br />Just my 2 cents worth

 

[mooseo]

Re: Electrical problems causing stall?

The motor has the switches on the port side and the flywheel covered. I have wing nuts on the batteries; first thing I learned when I started reading about this problem here is how bad an idea that was. I'm leaving them on until I get this problem solved because I have to keep dragging the batteries back to the garage to charge them. After that, I was going to use nyloks. <br /><br />I haven't looked at the stator because I have to find a wheel puller to get the flywheel off... think it is worth the effort?<br /><br />I didn't try reading the stator output with the motor running because it is so hard to get it going for any length of time. With a fair bit of cranking it will start, but run really rough for a couple of minutes and then cough itself out. I've checked my plugs and have good spark. I'm trying to figure out if replacing the rectifier is likely to have any effect on that problem?

 

[clanton]

Re: Electrical problems causing stall?

If you think the regulator is the problem, disconnect the 2 yellow wires, tape the ends and tie them away from flywheel. The charge coil voltage is to high. Check the voltage at the 2 yellow wires with the engine running. Check voltage from pack to coil. What kind and mfg meter<br />are you using now?<br /><br />Seahorse, the model number he posted says it is a 60 degree motor.<br /><br />Edited 4 June 2002<br /><br />Charge coil voltage spec is 250 volts with peak reading meter at cranking rpms.

 

[mooseo]

Re: Electrical problems causing stall?

Clanton, I'm using a Fluke 87 meter. You said that the charge coil should be 150 volts... how does it get too high?<br /><br />I have the VRO option. Will running the motor without the regulator connected cause problems there? I am pretty sure that it is still getting oil because it blows out a lot of smoke when it is trying to run. <br /><br />How do I check the voltage from the pack to the coil?

 

[clanton]

Re: Electrical problems causing stall?

I do not think the Fluke 87 will read peak voltage from the stator. I have a fluke 88 and it will not read peak voltage. I have an adapter for my fluke to read peak voltage. I would only run engine long enough with yellow wires disconnected to find problem. Check voltage from pack to coil with peak meter connect red lead to coil primary wire black lead to ground, check at idle and full throttle in water. 200 volts cranking, 130 runing.<br /><br />I was wrong on charge coil output V4 60 degree is 250 volts.I thought this was V6. If you have a Clymer manual, you should double check me on the specs.

 

[mooseo]

Re: Electrical problems causing stall?

Thanks clanton and all for your step-by-step help. I swapped the rectifier/regulator and that was definitely part of the problem. The battery is charging and the tach works now. <br /><br />Still have some issues, but thanks to all the help from this group, I saved one chunk of money.