So guys looks like my alternator is worn, question I have is based on the pictures do I replace the voltage regulator or the entire thing. The shaft is worn quite a bit. Oddly I JUST had this same exact issue with the BMW. Same BOSCH alternator design so I knew what to check. Thank god it is so easy to pull an alternator on LR. I was actually looking forward to this! lol

Between the shaft grooves and low brushes she is not making contact consistently. There is a low slight bearing noise and it spins very freely, but I can probably work with it. My main concern is are these grooves too much, normal?

Symptoms were sub 12v charging at random times when batt light was on. Otherwise it was 14.40ish when off. Battery seems to be just fine.

 

I would replace it, mainly because it would quit on me at the most inopportune time.

 

Pronouns. Meaning the whole unit not just the regulator? Normally I'd agree for whole unit, I did for the bmw, but this truck is day to day lol she is 170k miles and I'm shocked she runs most of the time. Dropping 300+ for a new one on this thing concerns me, especially when I need tires for the car.

Grooves in the shaft are kind of my decision, if these are OK for an alternator I would do the reg only, if these are a bit deep and abnormal I would replace. I don't have a gauge on how bad this is. My bmw one was 2x-3x as deep and the new alternator I put in that had zero grooves to start. A perfect cylinder of copper for the brushes to contact. I assume they wear down, but I have no idea at what rate.

 

I should have been specific. sorry. I have uses a real fine emery cloth and cleaned up the copper, and while being soft, brushes are softer and new brushes should give you new life.

 

So your vote is overall the shaft here is doable if I clean up the copper the new regulator with brushes are a good bet?

Anyone else vote the shaft is fine, just get the regulator with brushes and be done with it?

 

Just wanted to post a final answer for future searches.

Spun and listened to the bearings, there is a very tiny chirp happening once in awhile and faint grinding which to me signals imminent bearing failure as well. While I could probably get maybe another 20k on the alternator at best, it could seize and explode a bearing (I've been in that situation as well with another bosch alternator that was old). I would argue this wear on the shaft is indication of alternator age, you should replace the alternator if your regulator brushes are that low and groves are as deep as my pictures. Not doing so means you will be back in fixing this issue at a much shorter interval.

My bmw bosch alternator had a much more distinct noise to signal bearing failure, but was much further gone. It also produced a ticking that scared me to thinking lifters or oil pump failure was happening. Once the alternator in that case was replaced she sounded so much better. Clean and normal for once. I got a reman from a bosch core and they didn't replace the regulator because of margin, aka costed too much. I had to replace the regulator on that as well so beware. Just because a USA reman shop uses a bosch core local, you need to verify their work. (They covered the regulator cost when I told them output was 15v and lights were pulsing in the cabin. This fixed the issue and the alternator is good to go).

I imagine the odd random ticks I have been hearing on the Land Rover are from the alternator as well due to this bearing noise when I free hand spin it. It reminds me of the BMW one almost exactly when I got it off to do the same tests.

I will most likely be getting the 150amp upgrade new replacement for my ERR 6413 from BPUtah. I like the extra amps in case and it is not drastically more expensive.

 

if you can hear the bearing you either have to do a complete rebuild, bearing ,brushes and regulator or get a rebuilt.
I would go with a rebuilt because even if you replace the regulator, bearings and brushes , whose to say when you will loose a diode.
the 150 amp range rover alt is the way to go with the replacement, dont know what BPU wants but there a guy on ebay from CAlly has great price on new and rebuilt alternators and starters have bought a few with no problems