W123 Alternator AL129X upgrade, 65a to 115a charging system

The charging system on w123s is adequate at best. The factory alternator is an Bosch AL80X, which puts out either 55a or 65a. Not a whole lot when the glow system could draw nearly 100a on its own.
I've had glow relays stick on and drain the battery while driving.
If you're doing short trips, or lots of cold starts it could very easily run your battery low.
Those are problems I don't have anymore! This new alternator really puts out serious power, I've even jump started a school bus with my car with this alternator easily.
Here are some of the things you'll need to try this:
➡Bosch AL129X Alternator: amzn.to/45eVlzL
➡Remy Reman if the Bosch is out of stock: amzn.to/3UmSWAx
➡IR 231HA Impact: amzn.to/3P3X45m
➡IR 231 Protective Boot: amzn.to/3YIH7o5
➡Impact sockets: amzn.to/3E115kA
➡Excitation wire ring terminals: amzn.to/3YZEkHp
➡Crimper for small wire: amzn.to/3Phnjp6
➡4 Gauge terminals: amzn.to/44mhTxd
➡4 Gauge wire: amzn.to/44nGgKI
➡Crimper for 4 gauge wire: amzn.to/45AU1HL
0:00 Intro
1:20 Remove stuff
1:56 Pulley swap
3:05 Installation
3:54 Wiring modifications
7:07 MO Powahh!
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(These links are likely affiliate links which earn me a commission from your purchase at no additional cost to you, which helps me continue making videos like this!)

[@trythistv]

Here are some of the things you'll need to try this: Bosch AL129X Alternator: amzn.to/45eVlzL IR 231HA Impact: amzn.to/3P3X45m IR 231 Protective Boot: amzn.to/3YIH7o5 Impact sockets: amzn.to/3E115kA Excitation wire ring terminals: amzn.to/3YZEkHp Crimper for small wire: amzn.to/3Phnjp6 4 Gauge terminals: amzn.to/44mhTxd 4 Gauge wire: amzn.to/44nGgKI Crimper for 4 gauge wire: amzn.to/45AU1HL (These links are likely affiliate links which earn me a commission from your purchase at no additional cost to you, which helps me continue making videos like this!)

[@grantwest3951]

So grateful to find Try This TV. What a cool channel! Your videos are high quality and to-the-point. The links to the products help too. I'm a W123/W126 lunatic for life in Memphis with waaaaay too many. You have a good demeanor and voice for making content too, by the way. Thank you for sharing your experiences with the 123. I might just have to get into Sea Don'ts because of you! I hope one day we meet in person.

[@trythistv]

Thank you very much for the kind words! I enjoy making videos, hope they help other folks out, PWCs can sure be fun, they can also be a big money pit. Memphis isn't too far away, I'm over near Knoxville, I'd love to find or arrange a meetup for Mercedes owners, Been to a few real nice car shows around my area, very few imports of any kind though, Would be cool to see a whole bunch of Mercedes of any years met up, I struggle with logistics with that kind of stuff though. Some day I'll make some calls and see about some kind of meetup somewhere, see if there is any interest.

[@grantwest3951]

@@trythistv how do we make contact?

[@trythistv]

Best way is probably email me, tom AT trythistv DOT com

[@QsTechService1]

Will be definitely doing this mod to my 300DS Thanks for sharing when I purchase I will use your links

[@AlexOnParkwood]

Outstanding. Thank you very much.

[@AlexOnParkwood]

Tom, I emailed you by the way about delivery valves. Alex

[@trythistv]

I'm so glad you reminded me, your email got trapped in the spam filter, and yet somehow spam got through... technology is great huh? This is incredible, it looks like they're exactly what we need, I've got some on the way, they sure look exactly like the newer style dvs, this is great news!

[@AlexOnParkwood]

@@trythistv, I have a safety stock of fifteen to last me another fifty years.

[@vintage76vipergreenBeetle]

Nice information.👍

[@davidcarter4573]

Thank you for the interesting upgrade. PLEASE update this if the belts wear out quickly. More output is appealing but the power to turn a larger output alternator is (most likely) larger too. You have swapped from a poly vee pulley to a twin v-belt pulley designed to run with a 65 amp system.

[@trythistv]

I've had the al129x on since 2018 (I lost the video footage for a while) and I have not noticed any abnormal belt wear, I'm still running the same belts that I had on before I installed this alternator. I think it is likely a minimal difference in actual load, especially since it will rarely be making that peak 115A output, but the extra capacity helps keep the battery healthier especially in cold weather or making short trips because it outputs slightly more amperage across the entire rpm range.

[@davidcarter4573]

Thanks for the update. Sounds like a win!@@trythistv

[@chandima60]

Thank you very much for sharing your knowledge 👍🇱🇰

[@Engineerd3d]

I have been contemplating one of these alternators. They come from Saab 9-5 turbo cars.

[@Pitbullpower]

Hey love the videos man they have been a great help. Currently just had my alternator go out in my w123 but it seems that this alternator is no longer available. Everyone states out of stock. Any recommendations? Thank you

[@trythistv]

Have you called around local auto parts stores? They were optional on early 90s Saab 9000s, if you call for an alternator on a 92 Saab 9000, there was the al129x that is 115a and the al124x which was a 80 amp, most parts places can get the 115a one, if not, rockauto does have them as Remy branded reman, and BBB industries reman as well, and so does amazon: amzn.to/3UmSWAx

[@beeeah2548]

You use the D+ wire from the plug and use it as an exciter wire? Is the ,,idiot light" still working properly?

[@trythistv]

I'm not sure what D+ is, the blue wire on the original plug is the excitation which is connected to the "idiot light", so everything works just exactly like stock, just makes more amps.

[@LucianKel]

Well done, thanks.

[@LesterLovesWatches]

Will this Bosch AL129X fit onto all W123 cars? Mine is a 280E from 1982. Thanks for the great video. Are there any disadvantages from having the higher amperage?

[@trythistv]

From everything I can see your car should have come with the same al80x from the factory that my car did, so the al129x should fit and work perfectly fine. That being said, I've only put these on om617 powered cars, which covers a ton of body styles and years, but it should fit your car without any issue. As far as downsides, none at all. It keeps my battery happy even with short trips in winter time, and has been a no brainer upgrade for every Mercedes I've owned.

[@LesterLovesWatches]

@@trythistv Thanks. My mechanic has said that the wiring terminal is wrong; it should be a 3-pin plug. Maybe this is 280E specific, or year-specific. Anyway thanks for the vid anyway.

[@trythistv]

@@LesterLovesWatches It is not a direct plug in replacement, the original alternator does indeed have a 3 wire plug, 2 for carrying current and one excitation. In order to handle the higher output, this alternator does not use a spade terminal style connector like the original one does, so we run the new larger wire up and modify the excitation wire on the original plug to work with the higher output alternator.

[@danpicocfp6276]

Keep good going!

[@teesaeed6529]

is this alternator also equipped with a regulator or you have to replace the whole unit incase of failure ?

[@trythistv]

It has a removable regulator on the back with integrated brushes, held on by two phillips screws, Very similar, nearly identical setup to the factory alternator.

[@teesaeed6529]

Thanks a lot for quick response.

[@trythistv]

Of course! I happened to see your comment and knew the answer right away! I'm thrilled with how this alternator has performed on my cars

[@teesaeed6529]

I know now what to replace next hope it would work also on my 126 300sd 85.@@trythistv

[@trythistv]

You've got a om617, it'll work! I have been very happy with it, keeps my battery healthy!