Hey all, just wanted to ask for some opinions on what I should do with my "on the way out" alternator.

I assume it is original to the 2002 car with about 130k miles/~18 years, so it's getting up there in age and use..

For the last few thousand miles the gauge cluster lights have been flickering at idle and at low RPM driving. I can also hear a bearing noise from the engine bay at idle and low speeds. I am almost certain it is the alternator as the bearing noise gets louder when I turn on the headlights and quieter when I turn them off, loading and unloading the alternator. The noise if gone when I run it without the belt for a short time.

I already changed the tensioner and idler pulley bearings last year with new SKF bearings last year, they were very rough when I took them off.

So I now need to decide what to do:
1. Rebuild current alternator with new bearings + rectifier -> ~$50 in bearings + ~$215 rectifier = ~$265

• Front bearing = 31114-PT0-013
• Rear bearing = 31111-PT0-003
• Rectifier = 31127-PCX-J01

2. Buy used alternator from ebay/s2ki/etc. -> $???
3. Buy Reman alternator from Honda -> 06311-PCX-505RM = ~$425
4. Buy new alternator from Honda -> 31100-PCX-J02 = ~$1050.... Yeah right...

Has anyone done any of the above? What was your experience when you needed a new alternator? 1&2 seem like the most attractive options.

Thanks! -JZ

 

Did you ever jump start the car with a dead battery?

If so, you may have fried the rectifier.

 

It has not been jumped in my ownership. Has a good interstate battery in it, starts quick and strong.

 

$215 for a rectifier is highway robbery. I rebuilt my alternator with a new brush holder and rectifier for around $40 for both on ebay. These are not high tech parts and it has been running great for a year (flickering solved).

Rebuilding the alternator is very simple. Removing it is by far the most difficult part (though I did not need to replace the bearings). If you choose to rebuild take a look at the ebay parts. Here is what I bought:

Brush Holder

Rectifier

I haven't looked at what size bearings are used, but I would guess that you can get OEM replacements without buying through Honda as well.

 

Are these parts unique to the s2000? An alternator/starter rebuild shop I’m sure could help save some shipping cost.

 

They seem unique to the S2000 but I'm seeing "reman" alternator assemblies for my 2006 (31100-pzx-003) on line for under $125. The rectifier looks to be internal. Can go thru a lot of these before hitting the $1000 price point of a new OE unit.

I'd see what a local shop can do -- installed as these are a PITA to change. Plus you get some sort of warranty at a local shop.

-- Chuck

 

Thanks for the information and links guys. The ebay rectifier and brush holder are looking attractive.

So even buying the OEM bearings, the total would be close to $100, not terrible and definitely looking to be the cheapest method.
Rectifier = $33
Brush Holder = $10
OEM Bearings from Honda = ~$50

I think I can rebuild the alternator myself over the winter. I have access to a shop press and a lot of tools at work.
Would there be any other parts to swap out while I'm in there? Any pitfalls rebuilding these things?

How much are good used alternators going for? I can't find any for sale on the marketplace or any facebook groups..

 

I had the flickering lights. '06, 150k miles. Replaced rectifier and brushes with ebay partd a couple years ago and probably 25k+ mikes ago. No issues.

It was a simple job. Removing and replacing alternator was second hardest part of the job (which was pretty easy as you woukd imagine). Hardest part was holding brushes apart while reassembling. Just was awkward. But still pretty easy compared to some jobs.

Get the diy, and have at it. Don't be intimidated.

 

Are you sure you're not thinking of the starter brushes? There are 4 of them and I agree they are difficult to keep in place while inserting the rotor.

The alternator only has one brush and I don't recall that being much trouble.

Here is Soviet's excellent video:

 

my original rectifier was bad at around 4 year mark. i replaced the rectifier with oem, but did not replace the brush. 12 years and 150,000 miles later, it's still fine.

re-installing the alternator was pretty difficult with just one person.