Alternator internal component testing

A comprehensive video covering the testing of each of the main internal components of an internal regulator (IR) Alternator. Tests cover Rotor windings, Stator windings, Brush pack, Rectifier and Regulator units. Extremely useful information when trying to diagnose Alternator faults...any questions please ask, I check my Channel daily. Also check out Charging Systems ON CAR video too...

[@Kalkaekie]

I watched this video about 3 years ago and thought it was outstanding . I just wayched it again today, and will probably watch it again. Very good video !!

[@AndyMechanic]

Thank you :-)

[@copperkeyracing6167]

I fixed my alternator using this video. Taught me how to diagnose the problem. Found an issue with the 18:22 rectifier on mine, searched online for the part number and part I needed, ordered the rectifier and new brushes ($38shipped w/tax), installed them... tested it out at autozone... and tests showed 100% good. Previously, the test at autozone, showed bad. AWESOME!

[@BillSW]

where did u find brushes and rectifier?

[@danyo1972]

Great video explaining how all the components work. If your alternator fails it’s 99% caused by worn brushes. Before brushes completely wear they cause sparking which can damage the slip rings through overheating and premature wearing. If you get a red battery warning light on your dash don’t ignore it. Generally, swap out the brushes and you are good. The hardest part of any alternator repair is getting to the alternator and getting it in and out of the car!

[@krisea3807]

Best video to learn about how to diagnose Alternator for faults.

[@tanveernaeem1157]

An absolutely fantastic primer on alternators and testing their components. I wish my college teacher would have been that good. Hats off to you sir, and thank you for this great presentation.

[@schnabel69]

this is one of the best videos regarding inspecting and testing an alternator I have seen. Well done. Good explanation while still relatively technical. Thanks.

[@lazarousmayumbelo2921]

I must say this is one of the most clear explanations on the subject, well done. I would like to chat more off the social media if you don't mind, and this is my email [e-mail].

[@MrTsultana]

I never leave comments but have made an exception. Beautifully clear diction and video thank you

[@luukdeboer1974]

Excellent in depth, detailed explanation on alternator function. Very very very well done!

[@brokenmotorwagen1328]

I watched probably 10 videos already and still confused how to test an alternator. Once you explained the voltage regulator at 3:27" it all became clear. Thank you!

[@AndyMechanic]

Awesome! Really pleased to be of help. Thanks for the feedback too. Cheers Andy

[@VasileDiman]

The best video about how to test an alternator. Very good explained.

[@AndyMechanic]

Thanks :-)

[@madeljacky]

Definitely the best and easiest understood video I have seen on testing alternator components with a multimeter, exactly the video I was looking so I can repair my alternators rather than replacing them and not knowing why the failed, thank you Andy Mechanic for making this video.

[@alberta3157]

probably this is the best video out there on how alternator works and how to properly understand what's going on to fix it, thank you very much

[@albertotron74]

this was a great refresher for me, I used to this in my high school auto shop class

[@fishlegs100]

As others have said,I work as a hgv mechanic,but never really understood alternators,mainly due to the lack of this type of in depth training at college,what an excellent video thank you.

[@frankmenz1110]

Thanks Andy, especially for emphasis on the diode setting in the multimeter, I thought my rectifier may have been faulty, I just had to correct the setting on the meter, just as you mentioned, make sure it’s set for diode testing, the symbol popped up on the screen and then all checked out ok.

[@louf7178]

It doesn't get much better than this. Excellent!

[@nextphase7481]

The best video on KZbin describing how to breakdown and test the various alternator components. Excellent job! Just what I was looking for. Thank you very much!

[@brarautorepairs]

Helped me a lot diagnose my alternator. Turned our my stator had a break and was making contact with the windings. I wish I checked this before replacing the worn out brushes.

[@ericg.9836]

What a lesson! Thank you very much for this comprehensive video!

[@GeneralElectricCNC]

Thank you for a great video on testing the components of a Denso alternator! You explained all of the parts and their operation wonderfully. Not another instruction like this that I could find.

[@fjoladisviarsdottir8335]

I actually work as a car mechanic and I never really figured out how to measure an alternator when I was in school though we took some apart but this video has helped me a lot, finally I know how to test it. Thank you so much for a fantastic video!

[@AndyMechanic]

No problem, pleased you enjoyed the video. Cheers Andy

[@nesanesic9637]

Super klip,do sada najiscrpnije objasnjen rad alternatora!

[@seamasrigh2162]

Absolutely fantastic work. Thank you. I used to have fractional hp motors rebuilt (1970's) but no body does that anymore. Seeing this I really understand my vehicle so much better. I have found kits here in the States to rebuilt alternators. I'm amazed. Like you say shops won't do this because of labor costs but I can fix my own. Empowering.

[@danielkarl9916]

Great video Andy! I went to Unitech nearly 20 years ago (shout out to Duncan Wales). Great that that they still have guys like you!

[@NikisBurito]

Couldn't expect more informative video. WOW! Thanks a lot! You're doing a great job over there

[@patrickkabunga4526]

Patrick kabunga. thx very much for all those educative videos, you make me love my trade

[@arsaeterna4285]

what an excellent video, clear communication and all the information, much appreciated!

[@iambacktolifestartersalter7921]

I have had good understanding through your teaching. Thanks

[@sherabpuntsok2418]

Great video ! Very impressive ! Hard to find this kind of basic teachings nowadays ! I subscribed.

[@vmukal8430]

Excellent video on the very popular Denso alternator. Thank you for posting such an informative and useful (to me, at least) video. I believe your testing of the Denso regulator is maybe the only clearly explained one available.

[@markhughes4617]

At last, a real alternator video, not the dumbed down version we normally see on youtube! Thanks!!

[@AndyMechanic]

No problem Mark, pleased you found it helpful. Cheers Andy

[@ykmulwanda1638]

Andy check the time you posted the video and now(25/12/22) , I'm so grateful for the best lesson on alternator testing as I tried watching even by passing your video not knowing it had the full package. Thanks and happy Christmas to you and the family at large. Exceptional presentation ever!

[@dilkal1756]

Very well explained and well done! Enjoyed watching! Thank you !

[@AndyMechanic]

Cheers, appreciate your feedback Thanks. Andy

[@JWSmythe]

Damn, why didn't I find this video before? Anyone trying to fix an alternator needs to watch this. I'm not a professional mechanic, but I have been working on cars for friends and family for almost 30 years. Usually, I did the normal thing and replace the whole alternator if it was bad. On the car I'm working on now, a reman alternator costs about $160 locally. The whole rebuild kit is about $30. We need to get back to the old school art of repairing of parts, rather than replacing the whole part. That only serves to make the vendor more money, it isn't helping us at all.

[@AndyMechanic]

So very true. Cheers Andy

[@afzaalkhan.m]

Excellent stripdown and diagnostics

[@Raevenswood]

Your videos are always worth watching. This was great . I pulled an alternator at the junkyard today to use as a trail spare and I want to bench test it. I spent an hour looking at writups and videos of people testing output on the car but nothing that I needed to see. Then I thought I should check Andy’s channel and sure enough you have it covered! Cheers

[@jakobjdmh1524]

I've only just found you thanks to some land cruiser forums! I'm an automotive student at a polytech in tauranga and you seem like such a better tutor than I have, used this video to get my cruiser up and running

[@AndyMechanic]

Awesome, great to hear you like the videos. Good luck with your course. Cheers Andy

[@TheHalcorbin]

Excellent video....well put together...concise....ability to keep the viewers attention with your very clear and precise instuctions

[@michaeljohn8905]

This is a great refresher for me too. Thanks much for making this video. It’s so nice to be able to watch this and get refreshed when I havnt done one in a while. Thanks again. Michael. Liked and subbed. 👍

[@AldiShuli]

Thank you very much. It helped me to understand better how to check the alternator.

[@duncanmathias4331]

Thanks Andy, you explained it clearly and made it easy. I'm beginning to fix alternators now. Thankyou very much

[@billybaru3976]

This is an in depth training and I thought that I was in a class. Very informative and you took your time and spoke clearly. I'm not a mechanic but I'm trying to fix my alternator myself. On top of that, you also explained what each components do. You are a wonderful trainer and an educator. God bless you

[@andrewference1479]

Thanks for this vid, very easy to understand, no waffle. It does help that i was diagnosing this exact alternator from my AE86! found a couple of faulty diodes, so hooray, it isn't mystery wiring issues after all...

[@konstantinasnikonorycevas7615]

Thanks Andy ! Yours video is very good . You explanations easy to understand .

[@snipersquad100]

This is the best alternator repair video on youtube.

[@jeffs7267]

Excellent video! Thank you!

[@amootibob473]

thank you very much Andy sure am happy with your technology

[@jf3445]

Excellent teaching and useful technical revelations. Thank you.

[@flynick]

Excellent video...always check the rectifier first before taking apart the alternator, 90% of the time that's the problem, sometimes you can even get it off without removing the alt. from the car.

[@copperkeyracing6167]

Viewing Guide: Intro 0:07 Overview of the internal components 0:35 (Stator 0:50, Rotor & slip rings 1:29, Brushes 2:22, Rectifier 2:46, Regulator 3:26) What and how we will test the components 4:53 Testing the Single Rotor winding & slip rings 7:14 Testing the Three Stator windings 12:47 Testing the Rectifier 18:23 Testing the Brushes 26:24 Testing the Regulator 27:24 Conclusion of this particular Alternator 37:32 Assumption/Alternate test method for Regulator test 38:38 & 42:44 How to properly connect the earth lead in the Regulator Test (common mistake) 39:30 Conclusion 40:20

[@ntomdia]

Champ! Thank you!

[@hubercats]

Very helpful video, thank you!

[@hennieroets3189]

Thanks a lot. The best video by far!

[@AndyMechanic]

Cheers. Pleased you enjoyed it & thanks for the feedback. Andy

[@jimmymartinez3245]

A very detailed and instructive video. You have an understandable way of teaching. Other videos on the subject make my mind drunk.

[@AndyMechanic]

Thanks Jamie, I do my best & enjoy passing on what I have picked up over the years. Appreciate your feedback & here's wishing you a great New Year. Cheers Andy

[@edgardojualo8369]

Very well explained!! Kudos to you. Thank U

[@AbhishekSingh-iw5gn]

Very useful video. Thanks Andy 😊

[@vinces8974]

Excellent tutorial on alternators, thank you sir

[@craighrodgers8443]

Thank you the best explanation so far.

[@pnakogee55]

I found three alternators n took them home. Now that I saw ur video I can test them to find the problem n hope to repair them. I live in remote Community n this will help me a lots. Good video.

[@atomicdmt8763]

super quality video / information! well done. my brain just grew

[@orlandobudoo4414]

As an educator myself, I must say that this is one of the best videos regarding inspecting and testing an alternator I have seen. i must commend you as well on making videos of the topics you are going to teach. the students will learn much from them also they can be watched over and over again. Well done. Thanks.

[@AndyMechanic]

Thanks Orlando your feedback means a lot to me. Wishing you a great weekend. Cheers Andy

[@antonioromic9584]

Bravo,great explanation, thank you very much.

[@ivanvodopivec8022]

Thank you, this saved me soooo much money. Tested all but voltage regulator and found all defects (missing bolt) on ground from regulator. Now its working perfect. Thanks again.

[@AndyMechanic]

Great work...it's good to know the videos are helping people :-) Thanks for the feedback. Cheers Andy

[@promechanics2395]

Everything word near to perfection 💯

[@davidebyrne]

Hi Andy, Greetings from Ireland. Thanks, this is such a great video. I have never had to deal with an alternator issue before now. The instructions are so clear and easy to follow. I would have been lost only for this. The best thing for me (in all your videos) is the detail you go into to explain what each component does and not just simply, do this or do that. Keep up the good work Andy, I hope you are keeping safe and well during this Covid time. Take care David

[@AndyMechanic]

Thanks David, I'm pleased you found the video helpful, I appreciate you taking the time to send through your feedback. Also, I just got an email to notify me of a PayPal donation from you! Again, huge Thank You, I'll be sure to put it to good use. Thanks again & keep safe. Cheers Andy

[@kassahunmekuria4578]

It's Clear and very good briefing I would like to say Thank you

[@turbulentlord2617]

You are awesome in your video and it's descriptive nature. Very comprehensive then you're wearing a great shirt too!

[@arieln8203]

thank you, your video is what i am looking for

[@alvingarden4486]

Thank you for the indepth video.

[@rickmantv6012]

This video is very impormative for me.. clearly explanation..about alternator mechanism..step by step..one by one..up to assemble material.. thanks for sharing your video ser Appreciated.. great job..

[@gensyed]

very professionally done. congrats mate.

[@AndyMechanic]

Thanks Kimo for your feedback, that's exactly how I used to do it in class and the students enjoyed & understood it pretty well too. Andy

[@epiczone3828]

Andy Mechanic Well the recipetiers for the Alternator are below the feild winding because when it’s rewinding the Alternator needs to go through the fresh hold when it’s regulated through voltage, when they regulate between the Engine it spins because they are meticulously harder to spin with lower Voltage power through pin13

[@juliussinkala8417]

You are such a good instructor. I have really enjoyed watching your video. Keep it up.

[@GAURAV34330]

thank you for precious information

[@giftmutale4991]

Well explained, I got all your points well

[@royhellmann9018]

Excellent video for diagnosing the internal components 👍thumbs up!!! 17:13 USA

[@OmeizaADavid]

Impressive. Thumbs up for you

[@edfarmer154]

very detailed explanation! thanks for the help

[@AndyMechanic]

+Ed Farmer Cheers Ed, good to know you found it helpful. Thanks for the feedback. Andy

[@magnetjunkiepower8299]

Excellent video clear explanation and the very best I have seen!!Thank you sir.

[@pragasamsupiahs8419]

Excellent presentation on how to test each of the Alternator components.tqvm Sir.

[@michaelyawkal4592]

Andy Andy I love your Explanation

[@thetabascomex1]

Great video very good to explain it thank you greetings from Mexico 🤗🤗🤗

[@mc-ebert7542]

It's my best lesson ever.....Salute teacher Thx for vital information to me

[@artangjepali476]

BIG THANK YOU for this great explanation and presentation sir .very precise in every detail

[@bobismail1750]

Such an inclusive amazing detailed testing and analytical display A+++++++++ very valuable best regards ,Bob Alabama Parts company owner

[@AndyMechanic]

Thanks Bob, appreciate your feedback. Have a great day. Cheers Andy

[@grahamswain7356]

A very usefull video much appreceated .

[@nigelcopestake3618]

Excellent teach in, hopefully you will have saved me some money. Plus I have learned something 👍👍👍👍

[@dmmanju9705]

Thank you very much good & well learned information in detail a layman can under stand easily keep posting

[@AndyMechanic]

+D M Manju Thanks. Pleased you found it helpful. Cheers Andy

[@aliejaz581]

Superb sir very nice one of the best video in the youtube. To much detail explained i never know about to test diodes. Thanx a lot.

[@georgepapasozomenos6336]

thank u Andy very usefull information you cant find easy

[@AndyMechanic]

Thanks Goerge :-)

[@Kalkaekie]

Outstanding !!

[@daulloncox650]

You being very helpful and you very informative....thank you sir 👍

[@adamkremer1056]

excellent video!!!

[@Schaefft]

Excellent video, couldnt be better done!

[@rommelong6617]

Reliesko

[@kosamutauzeni196]

Hai Andy like the way you teach from Zambia

[@girishjayaraj427]

Sir great narration with video such a class room like the person who don't know about alternator just spend 50 minutes is enough to understand about it Very very thanks We waiting for more video from electrical world

[@leehotspur9679]

Well presented & Informative thanks for sharing

[@marcusdoolette1547]

Brilliant. Thanks heaps.

[@sergioramses2615]

This video is the best one i've seen on how to test properly an alternator :) i've been having trouble with my cars alternator the first time took it apart it was very dirty inside,oil,dirt,copper and brush dust clean everything i did see the brush rings one worn out more then the other and the brushes do seem worn out enough or there is no tension in the springs that they don't make contact with the rings but after saying all that i put it back together at first it didn't want to charge but after a couple of minutes it started to charge properly but after about 10 days it failed took it apart again put it together and it charged ok but then after 2 days it failed again.

[@avinashseedial5583]

Greatest video ever made on KZbin thank you sir

[@AndyMechanic]

wow! That's great to know. Thank You. Cheers Andy

[@georgebonney90]

Great video, thank you sir 👍

[@augosttweelve5370]

thanks for ds greet video sir andy...frm philippines.

[@kevinlewis8642]

Great video. I am now a subscriber!!!

[@patelnaresh4145]

Very good sir I am motivated