E46 BMW Social Directory E46 FAQ 3-Series Discussion Forums BMW Photo Gallery BMW 3-Series Technical Information E46 Fanatics - The Ultimate BMW Resource BMW Vendors General E46 Forum The Tire Rack's Tire Wheel Forum Forced Induction Forum The Off-Topic The E46 BMW Showroom For Sale, For Trade or Wanting to Buy

Welcome to the E46Fanatics forums. E46Fanatics is the premiere website for BMW 3 series owners around the world with interactive forums, a geographical enthusiast directory, photo galleries, and technical information for BMW enthusiasts.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.

Go Back   E46Fanatics > Tuning & Tech > DIY: Do It Yourself

DIY: Do It Yourself
Post here to share or improve your wrench turning skills! All BMW E46 DIY tips, tales, and projects discussed inside. Learn to work on your car and know the right BMW parts you will need!

Reply
 
Thread Tools Search this Thread Rating: Thread Rating: 8 votes, 4.63 average. Display Modes
Old 12-09-2005, 03:33 AM   #1
10bmw10
Registered User
 
Join Date: Dec 2005
Location: Bellevue
Posts: 112
My Ride: 2003.5 M3
DIY Alternator replacement e46

Ok, this is how i did mine, i hold no reliability on my install...so you cant sue me! The stealership gave me a quote from 888-1047.



TOOLS NEEDED:
Socket Wrench
3inch Extension
12mm 16mm 17mm 19mm
Pliers

First you take off your airbox.


...

...

After you take off the 12mm bolts and random plastic screw things this is what you'll see.


...

Once those parts are off disconnect the power from your top left corner of the engine bay. I believe it was a 12mm bolt.


...

Once you disconnect that power wire, disconnet the power wire on the alternator itself.


...

Next, undo the long bolt that is connected through the alternator.


...

After thats done, take the cover off from the pully thats attatched to the alternator. I believe its a 16mm bolt.


...

Closer look of the bolt you just took out.


...

Next get some pliers to hold the other pully firm so you can give slack to take off the belt.


...


...

This is what it should look like with your alternator off.
http://i26.photobucket.com/albums/c1...Picture011.jpg

Put the 12mm bolts back
http://i26.photobucket.com/albums/c1...Picture012.jpg

Put the plastic back
http://i26.photobucket.com/albums/c1...Picture013.jpg


Last reassemble the power wires! Follow your steps and its easy, it took me less than 40minutes to do, and ive only had the car less than 5days.

Thanks for reading, Brian
10bmw10 is offline   Reply With Quote
Ads by Google

Guests, get your FREE E46Fanatics.com membership to remove this ad.
Old 12-09-2005, 11:44 PM   #2
10bmw10
Registered User
 
Join Date: Dec 2005
Location: Bellevue
Posts: 112
My Ride: 2003.5 M3
Note to self, when taking off the belt from the pully, make sure your belt is lined up with the teeth so it stays on....or youll brake a belt like i did.

Next weeks DIY: How to change the main belt in the engine bay
10bmw10 is offline   Reply With Quote
Old 12-09-2005, 11:56 PM   #3
Alex
Mom says I'm a catch
 
Alex's Avatar
 
Join Date: Oct 2003
Location: Terra Sarda
Posts: 6,081
My Ride: E46
Send a message via MSN to Alex
Thanks for the write-up, good job.
__________________
A lap dance is so much better if the stripper is crying.
Alex is offline   Reply With Quote
Old 12-10-2005, 12:04 AM   #4
davidwarren
Halfway to 2L
 
davidwarren's Avatar
 
Join Date: May 2004
Location: louisville, ky
Posts: 2,505
My Ride: 2010 335i
I think you would be much better off disconnecting the battery, that is just a power access point. Also, there is a specific tensioner pully, it looks like you were wrenching on the water pully.
__________________

You down with UCC? Ya you know me!
sowing the seeds of jiggery pokery
davidwarren is offline   Reply With Quote
Old 12-10-2005, 12:16 AM   #5
10bmw10
Registered User
 
Join Date: Dec 2005
Location: Bellevue
Posts: 112
My Ride: 2003.5 M3
I saw the tensioner afterword, it makes it alot easier when you find that. I wasnt really wrenching, i just made sure it was steady when i pulled off the belt. When putting the belt back on, people will notice the tensioner and their life will be easier.

thanks for the compliments, im sure theres a more professional way out of a book, but i just winged it and it worked perfectly. Just make sure the belt is in the grooves!!!
10bmw10 is offline   Reply With Quote
Old 02-05-2007, 02:28 PM   #6
Titansilber3
Registered User
 
Join Date: May 2006
Location: Westminster, MD/Baltimore, MD
Posts: 358
My Ride: 323i
Send a message via AIM to Titansilber3
I cant get the alternator off everything is disconnected and the thing wont come off the engine. What do I do?
__________________
-Andrew
Titansilber3 is offline   Reply With Quote
Old 02-27-2007, 02:46 PM   #7
geko29
Registered User
 
Join Date: Dec 1969
Location: IL
Posts: 63
My Ride: 2000 323i
Quote:
Originally Posted by BMW323iE46 View Post
I cant get the alternator off everything is disconnected and the thing wont come off the engine. What do I do?
You're not going to want to hear this, but hit it with a hammer. seriously. Don't wail on it, just give it a good smack, and it should move a bit. Then you'll need to either rotate it a bit and hit it in the same direction, or hit it from the other direction.

I haven't changed the alternator on my 323i yet, but I've had to do this on every alternator I've replaced in the past (Sebring, Grand Prix, Dakota, Camry). They're fairly tight when they're new, add just the tiniest bit of corrosion and they're a pain to get out.
geko29 is offline   Reply With Quote
Old 03-20-2007, 06:53 PM   #8
bim323imer
Registered User
 
bim323imer's Avatar
 
Join Date: Oct 2004
Location: OC
Posts: 362
My Ride: slow e46
Does a new alternator come with a new voltage reg, or do u have to swap or old one in????
__________________
bim323imer is offline   Reply With Quote
Old 03-20-2007, 07:03 PM   #9
UnBreakable
Registered User
 
Join Date: Dec 2005
Location: NY
Posts: 444
My Ride: OB E46 328i
I did mine at 131,xxx miles as preventive maintenance. I replaced my originally installed Valeo with the Bosh. I did notice that the new alternator handles better the electrical load (heated seats, xenons and all interior lights on). Oh and The bosh alternator came with the voltage regulator already installed.
__________________
Image Hosted by ImageShack.us

-l-
'---0-(_)-0---'
UnBreakable is offline   Reply With Quote
Old 05-11-2007, 03:59 AM   #10
3rd_collective
ti-m-e
 
3rd_collective's Avatar
 
Join Date: Jan 2003
Location: NOVA
Posts: 2,371
My Ride: Alpine White ///M
Send a message via AIM to 3rd_collective
thank you, you're a life saver. I was just stranded on the freeway not too long ago and I'm pretty sure it's my alternator as my battery light kept flashing until my dash lit up like a xmas tree and the car shut off at 65mph. Luckily, I was able to roll to the side of the road. I flatbedded my car home and I'm now sourcing out alternators.

I hear alternator replacement at the dealer is $1k++
__________________
******************************************************
3rd_collective is offline   Reply With Quote
Old 05-13-2007, 02:46 PM   #11
3rd_collective
ti-m-e
 
3rd_collective's Avatar
 
Join Date: Jan 2003
Location: NOVA
Posts: 2,371
My Ride: Alpine White ///M
Send a message via AIM to 3rd_collective
I'm doing mine now and it so far, I've managed to extract the alternator. I'm having problems putting in the new one because the bottom brackets on the new alternator has really tight tolerances. I'm sanding down a little bit of the bracket mounting points so I can slide it in easier.

btw, M3's are a pita because there are metal oil lines right above the alternator.
__________________
******************************************************
3rd_collective is offline   Reply With Quote
Old 05-13-2007, 04:39 PM   #12
Gusagain
Registered User
 
Join Date: Apr 2006
Location: Where the BMW was born
Posts: 375
My Ride: '02 M3
Quote:
Originally Posted by 3rd_collective View Post
I'm doing mine now and it so far, I've managed to extract the alternator. I'm having problems putting in the new one because the bottom brackets on the new alternator has really tight tolerances. I'm sanding down a little bit of the bracket mounting points so I can slide it in easier.

btw, M3's are a pita because there are metal oil lines right above the alternator.
I just had my battery up & die on me. My friend ran an electric test on the car, the test was that the alternator was ok. Battery is deaded, off to the parts store tomorrow!
What year is your car? what milage are you at, wondering if I should start looking for an alternator too, just incase. I am at 34,XXX
__________________
'02 TiAg 6spd and Nürburgring junkie!
316rwhp
251rwtq

Sub 9 minute BTG laps at the Ring:

Custom tuned/// CSL headers/// HJS race cats/// Eisenmann LeMan exhaust/// 19" BBS AIR II CK's/// AutoSolutions SSK/// UUC LWFW and clutch/// Wilwood BBK 6 front & 4 rear/// Simota CAI/// H&R sport springswith Koni shocks/// UUC sways front & rear and some bling bling inside.
Gusagain is offline   Reply With Quote
Old 07-23-2007, 11:31 AM   #13
giver13
Registered User
 
Join Date: Jan 2007
Location: ft lauderdale
Posts: 420
My Ride: 01 330 ci
i noticed you only had to pull out one bolt. Isnt there a bolt on the bottom too. Im in the middle of it now and i cant get at the bottom bolt. Anyone know the size of bolt it is. Thanks
__________________
giver13 is offline   Reply With Quote
Old 07-28-2007, 10:31 AM   #14
tpapa
Registered User
 
Join Date: Jul 2007
Location: Raleigh, NC
Posts: 5
My Ride: 2001 330i Sport
Probably a 90A alternator

My guess is the chap that wrote this DIY was replacing a 90A alternator and not the 120A that's in the 330i/ci as I am into this repair myself and have discovered the *other* bolt. From talking to a friend with the maintenance manual the fan and fan shroud have to be removed to gain access to that second bolt. It may be possible to get it out without removing the fan but you'd need hands smaller than mine. I'm off in search of the requisite 32mm wrench required to remove the fan bolt (which by the way is threaded backwards - righty-loosy). If there's any sanity left at the end of this I may post an update.
tpapa is offline   Reply With Quote
Old 07-28-2007, 03:47 PM   #15
tpapa
Registered User
 
Join Date: Jul 2007
Location: Raleigh, NC
Posts: 5
My Ride: 2001 330i Sport
ok - so nevermind. The fan takes a special wrench which I'm sure is pointed out elsewhere in the forum. Got the alternator out anyway and have the bruised knuckles to prove it.
tpapa is offline   Reply With Quote
Old 07-28-2007, 03:54 PM   #16
tpapa
Registered User
 
Join Date: Jul 2007
Location: Raleigh, NC
Posts: 5
My Ride: 2001 330i Sport
a little off topic but if anyone is interested in the fan removal step it's detailed very well (as is the special tool) in this article that's is also referenced in the under-drive pulley install posts on this forum:

http://mywebpages.comcast.net/jns-jo...leyinstall.htm
tpapa is offline   Reply With Quote
Old 07-29-2007, 01:44 PM   #17
tpapa
Registered User
 
Join Date: Jul 2007
Location: Raleigh, NC
Posts: 5
My Ride: 2001 330i Sport
I just wanted to toss a few lessons-learned out there for those that consider the DIY alternator change.

1. It is a very doable DIY job so don't fret. My process and setup was different from the original authors and yours will probably be different than mine.

2. If you have the mechanical fan (connected to the water pump) take that out first. It may be possible to do it with it in but after fighting it for a day and then taking it out I could've saved myself hours on the job. There are some good articles out there on removing the shroud and fan. As I find them again I'll post them here.

3. Apparently not in all, but some alternators have 2 mounting bolts, not 1 like the original author of this post. Not sure what the rule is there but I'm sure someone does.

4. Tools - you need a special tool to hold the pulley on the water pump so you can remove the 32mm bolt that attaches it to the fan. You can buy this (@ bavauto for $40) or you can make it like I did. I'll post a pic later. In addition, have a good selection of metric sockets. I recommend 5mm-19mm, 3/8 drive, a 3 inch extension, and a breaker bar - you won't use all of the sockets but you'll thank yourself later for having them. You'll need a 32mm wrench (mentioned above and also for sale at bavauto for yet another $40) but I couldn't find one quickly so I used a crescent wrench that opens to 35mm - 10" cresent. Lastly, to de/re-tension the belt, you'll need a T50 torx wrench. I got the kind that connects to a 3/8 drive wratchet.

5. Before you start draw a quick little map of the belt's path around the pulleys. You think you'll remember but if it's your first time, and after a few hours in the hot sun and a few beers you'll question yourself as you put it back on.

6. I'm surprised that there isn't more information on alternator replacement on this forum but perhaps it's such an "easy" thing to do that no one feels it noteworthy. A newbie like me could've used more detail. The good news is that it's out there, in other posts and forums under searches like "water pump replacement", "belt replacement", etc.
tpapa is offline   Reply With Quote
Old 07-29-2007, 03:13 PM   #18
tpapa
Registered User
 
Join Date: Jul 2007
Location: Raleigh, NC
Posts: 5
My Ride: 2001 330i Sport
BTW, I was at 80K miles and I got the alternator at the stealership because I needed it ASAP (on a Saturday) and none of the local parts stores had one. I paid $370 including $30 core. My stock alternator was the Valero 120A. You can get this for much cheaper elsewhere if you have the time.
tpapa is offline   Reply With Quote
Old 07-29-2007, 03:28 PM   #19
Custom3
Registered User
 
Join Date: Sep 2005
Location: Dirty Jersey
Posts: 5,443
My Ride: HellRot 330CI
sweeeettttt.....nice writeup
Custom3 is offline   Reply With Quote
Old 08-05-2007, 06:07 PM   #20
vids_blk323Ci
• DFW •
 
Join Date: Dec 1969
Location: DFW
Posts: 2,732
My Ride: JB 323Ci • SP • PP
Send a message via AIM to vids_blk323Ci
10bmw10 and t-papa good writeups!
__________________

Dinan Stage I S/W | ACS RSB | ///M FSB |UUC TMEs & Pulleys |Ate Slotted Discs | ScanGuageII | RockyMounts MTB Carrrier | OEM Rear Clears | LED Euro City Lights & Rear Fogs | Two-Tone Suede DIY | ACS Pedals | Bimmian Gauge Rings & M3 Face | Smoked Frnt Corners w/ Luxeon LEDs | EAS CF Roundels | JLevi Ti CF trim | Blk Suede shift/ e-brake boots | ECS Smoked Frnt Bumper Reflectors | DICE Duo
vids_blk323Ci is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Censor is ON





All times are GMT -5. The time now is 12:26 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
(c) 1999 - 2011 performanceIX Inc - privacy policy - terms of use