Alternator Replacement Video - Stabilized HD

[suprarx7nut]

Here's another real simple video showing the replacement of the alternator on a mk3. Mine wore out after I let my huge Die Hard Platinum die a few times over the winter (charge your batteries or disconnect them!) and jump started and let the alternator *try* to recharge.

I also used Youtube's built in stabilization feature which worked pretty damn good. I filmed it holding my phone with one hand and with the software feature turned on sometimes it looks like it's on a gimbal or tripod. Pretty neat how it turned out considering my setup is so unprofessional.

https://www.youtube.com/watch?v=da6RogFYoTQ

Part: Denso 210-0158 Reman
Price: $137.26 plus tax via Amazon

Enjoy and let me know what else you want to see!

 

[jetjock]

Nice job. Fwiw I preferred to overhaul mine rather than replace. Not hard nor expensive to do. Need a rattle gun though.

 

[suprarx7nut]

I kept my old one to do just that actually. I don't have access to my tools to do it now but I will later.

If it's just not outputting enough voltage at lower rpm, what component is that which is worn out? I spent a few minutes on Google and couldn't find that info.

 

[jetjock]

Could be a bad connection to the field connector, bad regulator, brushes, or a bad rectifier assembly. The stator and field windings are a different story. Replaceable but not worth it. Assuming those are good overhaul involves cleaning, replacing both bearings, polishing the slip rings, and new brushes/brush holder. The TSRM has the full procedure. That said if the slip rings are shot from the brushes being worn to the springs you're out of luck. Btw if the ALT is on the car a quick check for faulty diodes is to measure ripple across the battery with the meter on AC. Course, a scope would be even better.

 

[suprarx7nut]

Could be a bad connection to the field connector, bad regulator, brushes, or a bad rectifier assembly. The stator and field windings are a different story. Replaceable but not worth it. Assuming those are good overhaul involves cleaning, replacing both bearings, polishing the slip rings, and new brushes/brush holder. The TSRM has the full procedure. That said if the slip rings are shot from the brushes being worn to the springs you're out of luck. Btw if the ALT is on the car a quick check for faulty diodes is to measure ripple across the battery with the meter on AC. Course, a scope would be even better.

Ok, gotcha. I looked at ripple in a previous project car so that's familiar. Unfortunately, I didn't have my DMM handy this time around (It's a few feet deep in my crap in a storage POD somewhere in Phoenix).

I'll hang onto it until I get into my next house and have the garage shop back up. I don't have a good compressor for an impact, but that is on the shopping list for the new place. I'll get that nut off one way or another and step through the TSRM process. It'd be neat to step through that just for my own future reference if nothing else.

Thanks for the tips, JJ.

 

[jetjock]

You be welcome. Keep in mind the typical alternator doesn't put out much at low rpm. It's the nature of the beast. I had to put a different pulley on my DMC12 for just that reason. Downside with doing that sort of thing is the alternator can be over spun at the other end and possibly disassemble itself.

 

[supraguy@aol]

JJ- i had a concern about my alternator. Mine seems to work just fine, but i
Was worried that it was running too hot. I find that going from a cold start(80f ambient) to a
3 minute idle, will bring the temperature of the case up towards 150 degrees. Does this sound normal.
No electrical load at all, just the engine's electronics themselves. All else(lights, fans)is off.