Briggs & Stratton Battery Not Charging - Simple Voltage Regulator Test 

This video was made Jul 24,2016 and it is still helping others thank you so much!

loved how you explained every step. and gave a few methods of testing. couldn't make it any easier unless you come and tested it for me.

Absolutely fantastic video. You clear up more questions in this video than the past 10! Great demonstration(s) From start to finish thankyou for your time for any and everyone watching this video!

Excellent demonstration! Thanks for showing both the problematic and functional setups so the viewers knows what to expect in both cases. This gives a bit more confidence to the do-it-yourselfers out there.

Best explanation I have seen on this. Same goes for my Harley. What people need to see is how to use a voltmeter.

So so helpful. My voltage regulator failed, and when I tried a new one, I got no voltage out of the regulator when not hooked up to the system. I tried a third regulator and got the same thing. As you pointed out the output voltage from the regulator is dependent on whether or not it is plugged into the system. I never would’ve thought that. Thank you so much.

Thanks for taking the time to share your expertise on this subject. You save me lots of time trouble shooting. Excellent video, just the right amount to detail saved me the cost of a repair manual. Just needed a new regulator !

Thank you for your time in sharing this information.... EXACTLY what I was looking for!

Great job putting this together. Concise, to the point and covers all possible issues.

This is the best expained video I have watched on youtube. Told me exactly what I need to know. I will check my dads mower tomorow. Thanks for the well explained info and your time.

Great video! This made it simple & helped me diagnose my hustler super z. I couldn't figure out if it was the regular or the alternator. I was confused about how to test the system, But after your video I checked it. And it's the regular. Thanks!

Nicely done sir. I'm running a 2007 Simplicity Broadmoor and my first thought was that mice and gunk had gotten into the alternator coil, but after pulling the flywheel it looked practically brand new. This was my next culprit. Thank you for the side-by-side good/bad comparison.

That was the most helpful thing I have ever seen. Brilliant.

Thank you very much for this video. I figured out that my battery was not charging but had no way to tell what has failed. Brilliant video!! You may have save me some money and time. Great job!! Best I've seen.

Thank you very much for your excellent video explanation. I followed your instructions on a kohler command 16 HP not charging and narrowed it down to no ground at the rectifier. Added a ground wire from battery to rectifier and system charging at 14.7 volts. 15minutes and 2 foot of wire to fix at ZERO cost.

This sir is the best demonstration I seen on RU-vid yet great job

Very Good! Short and to the point. Good to know it has to be tested under load. Thanks.

Exactly the information I was looking for. Simple and sweet, thank you

Very straight and to the point. Very nice job. Quite informative also. Thanks for keeping it pretty simple and easy to follow.

Excellent video! Very specific, detailed and easy to follow. Thank you! Your video was extremely helpful and allowed me to troubleshoot my JD LT145 and get straight to the problem (imagine that, it was the voltage regulator!). You definitely saved me $$$. Just wanted to say thanks for taking the time to help us 'do it yourselfers'. 👍👍👍

Great video and just what I needed to diagnose a Scag with 23 HP Briggs Vanguard on it. Turned out to be a simple sheared bolt on the frame that held the negative/ground lead from the battery - but I was ready!

Excellent short video. I was going to comment, no power output without battery hooked up, but you got that also! Thanks,

Excellent video mate! I'm a light vehicle motor mechanic by trade (cars/4wd's) only played with small engines a few times (push mowers/chainsaws). This has to be the best alternator diagnosis video I've seen! Helped me out with my ELS656 Briggs. Keep up the good work. Kind regards from Australia.

Thanks for taking the time to share. Nicely done. Short and to the point.

Good and very informative video. Sounds like your valves need adjusting because of the way it turns over when starting. Thanks for the video.

Great diagnostic and institutional video. Straight to the point great job

Many Thanks for this video. This really helped me to diagnose a friends riding mower. Now I have to break the bad news to him and let him know that the regulator is about 80.00 and he is going to need one.

This is an excellent video to test the voltage regulator/alternator. Just a suggestion, your tractor is hard starting indicating the need to adjust you valve clearance (too wide of gap causing not allowing the compression to be released properly).

August 2021: Knowledge is power! Ordering a new regulator. Thanks very much!

Great video. Thank you. Been having the same problem with new battery keeps going dead. Volt meter at the battery while running should be closer to 14v and mine is only 12. I will check my regulator like you now. Thanks again!

Great video! Straight to the point. Just enough explanation, no fluff.

Thanks for this vodeo, I was wondering why my new alternator wasn't charging my battery

This was quite informative, helpful, and well done. Thank you.

Really helpful demonstration. Thank you. Colin L Beadon

Excellent video and concise directions…….pretty darn professionally done! 👍

Top notch video. This explained it clearly & to the point.

Great simple explanation of the charging system.

Wow! one of the best videos I've seen. Simple, yet precise.

Absolutely the BEST explanation on here. There are DOZENS that tell you little or nothing...mostly guys that must have NO one to talk to or trying to show how BRILLANT they are.....

Good vid. Often times the stator has a weak output as well. It should be around 30ish

Wow. Mystery solved! Thank you so much. It was a real puzzle on the low voltage reading without a jumper. Thanks!

Thank you ! A lot of great information in a timely manner . 👍👍👍

This was very helpful. Thank you Sir

Excellent tutorial that helped me solve my own problem. Well done. Thank you.

Thank you so much for making this so easy to understand. I have spent days trying to figure out what what wrong with my mower. After replacing the starter, solenoid and the battery it wasn't till I came across your video that I finally was able to figure out that I just needed a new regulator. Your Brilliant!!!! Thank you so much

Great video, I wish I would have seen this before spending the $70 on the stator replacement only to have the problem persist. Ran the tests and DC voltage from the VR showed only 12.49. New VR here we come.

THAT WAS GREAT! About the time Mr. Know-It-All (me) gets cocky, here comes a mower with a problem I did not know how to fix. From the Era of My Corona... ...THANK YOU --- THANK YOU ---- THANK YOU. Mr Brown, North Central Florida, 3/31/2020

Thanks for your helpful video. It helped me to quickly determine that I had a bad regulator on my John Deere riding mower.

Good details in this video helped Me troubkeshoot my voltage regulator problems! Thanks!

Simple explanation and diagnosis!! great job! Thanks

HELPED A LOT!! My voltage regulator needs replaced.

Thank you sir... heavy on the SIR ;) Very good video. Clear, concise and accurate.

Thanks for the video. I have the same engine and got the same 30 volts out of the stator and 5 volts out of the voltage regulator.

Excellent demonstration!

Thank you! I am seeing my dash voltmeter jump all around and I suspect a problem in the charging system. I will follow your guidance to diagnose my gut feel which is the regulator before I buy a replacement.

Darn good information and you presented it in a way we all can understand. Solid thumbs up Snap Roll! I just inherited a Walker with this very problem.

Excellent video! Simple and to the point! Other you tubers take note!

Thanks for posting this very informative video. Thumbs up !

Mine wasn't charging, also the ammeter would fluctuate and the lights would go bright and dim etc. Your vid showed me how to troubleshoot and replace a bad regulator. Thank you!

Awesome video very straightforward appreciate The demonstration

excellent vid cus to the point & just what one needs to know. ac voltage, dc voltage & amp

This was quite helpful, was able to fix my Dixie Chopper via this troubleshooting video.

Great demonstration, Thanks!

Thank you. This will help me get an old Craftsman 18hp B&S running!

Good video! My mower used to hesitate like yours does.Yours could be because the battery is low possibly...My mower hesitated similar as yours does but it was because the valves needed adjusting...just a tip .Hope it all goes well..

This video was extremely helpful thank u very much👌

Beware NEW voltage regulators that are bad out of the box. I bought one on eBay, installed it, no charging. Returned it, got a second, again, no charging. After tearing the mower down, looking for faults, I found none. Everything pointed to the NEW regulator being bad. In addition to the AC test in this well done video, I have a few tips for people in similar situations. First off, my mower has a built-in ammeter so I noticed that the new regulator wasn't charging right off the bat. Most mowers don't have those and I can only imagine the scores of people who installed a new regulator thinking their worries were over only to find their batteries dead several months after the warranty on the new regulator was expired. The simplest way to check to see if your charging circuit is working is to start the mower and measure the voltage across the battery. It should read about 14.5V - not 12.7V. The battery needs the higher voltage in order to charge. To test the stator, use the AC test as described in this video. The engine should be at full throttle and actual AC voltage should be what the manufacturer specs say. I also load tested the stator by connecting a 12V light bulb to the output. At low RPM, the bulb will light, at higher RPM, the bulb will blow. Incandescent light bulbs run fine on AC. In my case, the bulb drew about 2 amps from the stator with no problems. Next, I hooked the same 12V bulb up to the mower wire that connects to the output from the regulator. The other bulb lead connects to ground. Then turned on the ignition switch. The bulb lit up indicating there was no break or hidden blown fuse. Finally, I bought a 25 amp bridge rectifier from a local electronics store and hooked the AC input to the two stator wires. The positive (+) output of the rectifier connects to the mower wire that the regulator output wire would normally connect to. The negative(-) output to battery ground. When I started the engine, I immediately saw the full 13 amps going through the ammeter and into the battery. This was proof positive that the charging circuit was fine except for the NEW regulator. It should be noted that the bridge rectifier connections were for testing only and the battery will be ruined if you run it like that for very long. The rectifier converts AC to DC, but does not regulate the voltage to a safe level. Hopefully this will save other people from having a dead battery because their NEW regulator doesn't actually work.

Perfect Diagnosis thanks a bunch man

Thanks, helped me rule out buying the more expensive parts. Regulator on the way from Amazon.

Excellent video! Thank you .

Excellent video. Thank you.

Excellent diagnostic video! Thanks.

everything you need to know, well exsplaned to fix the charging fault. Js

Awesome, easy to follow and extremely informative!

Yup, exactly what I was needing to know. Thank you!!😊

Thank You so much for this vid!!....I only have a little over battery voltage(12.6 volts) leaving the regulator and am going to order a new reg. Fuses ok & new battery...... THANK YOU!!!!!!!!

This is perfect as I have the same issue with the identical riding mower/engine combo.

Good explanation Pretty sure you were reading ac from the regulator, the bad one had 5v ripple, the good one much less Time for a valve adjustment btw..

Best video on the subject. Excellent work! 👌

Excellent, excellent video. Very well done, obviously by a knowledgeable and experienced man. Thank you very much.

Great Video!! Very well made.

This Helped a lot! Thanks for posting this.

Thanks. This solved my problem.

Great how to video, thanks for posting.

Wow! Fantastic video!!!! Well done....thank you. :)

You got to the point in under 5 minutes! (Unfortunately I have no stator ac voltage)

Sounds like you might need valves adjusted so not getting that bog when turning the key to start. Great video.

GREAT Video. Thanks!

Thanks, very helpful

The Best video!!!! Superb!!!

Thank you. My John Deere SST16 will run like a charm.

simple direct helpful. i like the good & bad so can compare

Thanks. Much appreciated.

Excellent video. Thank you

very nice vid and good explanation. thank you

Excellent video !!!

Thanks for posting. Quick question. From alternator i have 50 volts out. When engine not running and i connect alternator cable to regulator cable it smokes. I have 12 volts in regulator cable. So if running i will have 12v and 50v ac hitting each other. Should there be 12v dc where alternator cables are going in?

Fantastic informative video thanks

Very helpful ! Thanks ! (:

Thank you man!👏