No electrical output from my engine

[C5Engineer 1170]

My charging system recently quit working so I started troubleshooting. I thought it was my Voltage Regulator but after more troubleshooting I realized that I was getting no AC voltage from the yellow wires coming off the lighting coil. Whats weird though is when I hook up the regulator and have the engine running I'm getting a small amount of voltage coming off the regulator output wire. It was giving me 4.8 volts at 3000rpm and 1.4 volts at idle. With the regulator unhooked and testing for AC volts right at the yellow wires with the engine running it was reading zero. Pretty weird. Anybody have any suggestions on anything left to check or troubleshoot before I pull my motor?

Who's had their flywheel and balancer off? Anything cosmic about it? I already have a stator and puller on the way.

[Av8r3400 1179]

Bummer, Joey.

I don't know much on these, but I may be getting together tonight with someone who does. (He's at least extremely familiar with the 503 systems.) I'll pick his brain a bit...

[6320012s 12]

I had trouble with my charging system a while back and found I had burned up my VR. While researching the problem I found that these charging systems need a constant load or they have trouble. As far as your symptoms, don't you have to have a working VR to excite the alternator?

[Av8r_Sed 82]

Check for continuity of the lighting coil between the yellow leads with an ohm meter after disconnecting from the voltage regulator and without the engine running. It should be pretty low, like 1 ohm. If it's open, the coil is likey toast.

The lighting coils on Rotax motors don't work like an alternator and don't need any excitation in order to function.

-- Paul S

Edited 19 Mar 2012 by Av8r_Sed

[C5Engineer 1170]

Thanks Paul another guy at the airport said the same thing. Gonna have to give it a try.

[Av8r3400 1179]

That's exactly what my guy said, too. (Check for some resistance between the leads.)

[C5Engineer 1170]

Either way I'm going to have to pull the back of the motor off. My new stator and a Rotax puller will be here on Saturday. I am going to attempt to leave my RV reservoir hooked up and just lay the engine with the plugs out on my bench. If I can do the engine pull will go pretty quickly. My water was due to be flushed and changed anyways.

Hoping it's a simple stator change and that will be the end of it.

[ChrisBolkan 130]

Either way I'm going to have to pull the back of the motor off. My new stator and a Rotax puller will be here on Saturday. I am going to attempt to leave my RV reservoir hooked up and just lay the engine with the plugs out on my bench. If I can do the engine pull will go pretty quickly. My water was due to be flushed and changed anyways.

Hoping it's a simple stator change and that will be the end of it.

Hi!

Take great care not to move the ignition timing sensors if you replace the stator. Or make sure you can put them back in exactly the same place! And also be sure to lay blankets or towls under the engine so you don't pick up any metal filings on anything magnetic. Otherwise a pretty easy job to go in there and work. Also pay close attention to wire routing so nothing that rotates nicks the wires. I attached a couple pics so you can see what's inside there before digging in, incase you haven't been there before.

Chris Bolkan

[ChrisBolkan 130]

Hi again Joey,

I'm attaching the complete hard to find Rotax repair manual. I couldn't find a files location on this site, so I'll post it on this thread and someone in the know can move it where it belongs. The file is large and in 4 pieces. If you print out all four files and arrange the pages, you will have the complete manual. This is the best documentation availabel for Rotax two strokes if you do your own work.

All the best,

Chris Bolkan

odd pages 1-83.pdf

even pages 2-84 in reverse.pdf

odd pages 85-end.pdf

even pages 86-end in reverse.pdf

[C5Engineer 1170]

Wow Thanks for taking the time to do that Chris!!

[marshawk 82]

Wow Thanks for taking the time to do that Chris!!

Yes thanks for the rotax manual ,I'm sure I'll need it sooner or later,btw the cowling is coming along pretty well on my other project

[akflyer 1427]

All of the manuals are uploaded in the Engines thread. The installations, maintenenace, rebuild etc. I will pin them so they stay at the top.

[C5Engineer 1170]

Time to update this thread. I started on my plane at 630am on Saturday. I had the engine on the bench by noon. My stator and pulled arrived at 3pm and I went back to the hangar and replaced the stator and cleaned and inspected everything so it was ready to go back in Sunday morn. Started at 7am on Sunday morn and had it fired up and leak checked by noon. It's now running at 14 volts again. Thank goodness!! Pulling the motor alone is fun! Not really.

Pretty good weekend job considering the motor now has new exhaust gaskets, pulse line, fresh plugs, and new gearbox oil and coolant all in a weekend. It was nice to put eyes on everything too. I will post pics of the old stator tomorrow.

[ChrisBolkan 130]

Time to update this thread. I started on my plane at 630am on Saturday. I had the engine on the bench by noon. My stator and pulled arrived at 3pm and I went back to the hangar and replaced the stator and cleaned and inspected everything so it was ready to go back in Sunday morn. Started at 7am on Sunday morn and had it fired up and leak checked by noon. It's now running at 14 volts again. Thank goodness!! Pulling the motor alone is fun! Not really.

Pretty good weekend job considering the motor now has new exhaust gaskets, pulse line, fresh plugs, and new gearbox oil and coolant all in a weekend. It was nice to put eyes on everything too. I will post pics of the old stator tomorrow.

Schweet! Glad it went well!

Chris

[chopndrag 226]

Now I'm in the same boat . I have a lighting coil not working .