Replacing The Voltage Regulator In A Fuel Injected Beetle

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dtrumbo
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Replacing The Voltage Regulator In A Fuel Injected Beetle

Post by dtrumbo » Mon Feb 28, 2011 7:49 am

So you're driving along and all of a sudden your instrument panel lights brighten, your wipers start wiping faster and your Blaupunkt radio shuts itself off. Poltergeist? Aliens? No, your voltage regulator has stopped regulating and you have a moderate to severe over-voltage situation. Oh sure it's nice having the brighter lights and the peppy wipers but I'm pretty sure your ECU is saying WTF?!?! Alright then you decide you better do the right thing and replace your voltage regulator. Well if this was your 1978 bus it would be about a five minute bingo, bango, bongo. Well this isn't your 1978 bus, this is your 1979 fuel injected Beetle. The process is a little more involved. Let's get to it.

The first thing you'll notice is... you can't find the regulator. Oh, that's because it's INSIDE the damn alternator!! Oh how handy and thank you so much to the fine folks at Bosch for putting it in such a readily accessible place. I guess they're all that way nowadays, but I still find it annoying. This means removing the alternator is in order. On carbureted vehicles this is much easier but we've got the "modern" fuel injected model and seemingly as all "modern" technology goes, this is shaping up to be a royal PITA. Allow me to share this character-building experience with you all.

The first thing you want to do when doing any kind of electrical work is to remove the ground connection from the battery.
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Then, remove the engine compartment lid. This seems like extra work, but trust me. Completely remove the hinges, again, trust me. Now here's what we have to work with.
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Since you can barely even see the alternator in the above picture, it seems we're going to need to start removing stuff in order to get some access. Remove the air cleaner, AFM, intake S-boot. This will get you to this point.
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You're on a roll so go ahead and disconnect the electrical connections from the alternator, remove the throttle body, remove the injectors and cold start valve from their mounts so you'll be able to rotate the fuel rail that crosses the engine in front of the fan shroud forward and out of the way. Disconnect (and remember where they go) any hoses or other stuff that's in the way. The ultimate goal is to remove the fan shroud with the alternator as a unit. This is why the deck lid hinges need to be removed so that you'll have enough room to get the shroud out of the vehicle. If you haven't already, remove the alternator belt and loosen the two screws on the bottom of the left and right side of the fan shroud. If your car has a thermostat, disconnect it from the rod that actuates the flaps. You will also need to remove the alternator hold-down strap. Unless I've forgotten a step (and I almost certainly have), you will now be able to lift the fan shroud up and out of the vehicle.

Here 'tis on the bench.
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Look, ma! No flaps! (That will the subject of a completely different topic)
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Now you can easily remove the alternator from the fan shroud by removing the four (three in my case, thanks PO) bolts that hold it in.
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The faint cries from our poor distressed regulator are slowly but surely getting louder, but we've still got some stuff to take apart to get to it. Next is to remove the fan from the rear of the alternator. Use this:
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with your alternator secured in a vise or some-such like so.
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As with everything you ever do to your vehicle, DO NOT LOOSE ANY OF THE PARTS OR GET THEM OUT OF ORDER FOR REASSEMBLY!

Once the fan is off, here is what's left.
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See the little black square with the spade terminal held in by the three screws? Don't touch it... yet. Maybe later, but not yet. Now remove the backing plate by removing the two nuts shown below. The regulator's cries are getting even louder now, we're getting close.
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Now you'll need to use a puller to remove the fan hub from the alternator shaft. Like so...
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Again, don't loose the woodruff key, the hub or the bushing that is under the hub.
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We're really close now. Use your puller to GENTLY remove the back plate from the alternator.
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There she is, like a trapped Chilean miner that has waited so very long to see the light of day again.
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Out with the old, in with the new.
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The wires connect underneath that little black square with the three screws. Depending on the size of your digits, you might be able to attach the wires as-is. Otherwise, remove the three screws so you can lift the square doo-dad out far enough to get the wires attached.
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To quote Bentley "assembly is the reverse of the above procedure" or some such BS like that. Seriously, just retrace your steps and it goes back together just as easy (HA! HA! HA!) as it came apart. I replaced the bearings in my alternator since I had it apart. This is optional and since this whole process is one of those things on everyone's "bucket-list", I know you wouldn't want to cheat yourself out of doing this all over again when your bearings fail. If you decide that once is enough, the rear bearing is located in the black rear cover and the front bearing is appropriately located here.
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Don't loose the spring-washer doo-dad shown here.
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Here's the front bearing ready to be pulled.
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BE GENTLE WHEN PRESSING THE NEW BEARINGS ONTO THE SHAFT! Make SURE you support the shaft on the opposite end from the one you're pressing the new bearing. I used a deep socket and hammer to gently press the bearings on to the shaft. The bearings are readily available. I got them at W.W Grainger which is a nationwide industrial supply house. Your FLAPS probably have them too. They're quite common. A co-worker of mine rattled the numbers off the top of his head and he's never owned a Volkswagen. Apparently they are used in alternators of all walks.

In my flair for the dramatic, I may have made this sound harder than it is. On the other hand, I know I've skipped over a lot of details that you'll curse me for later. Take your time and be meticulous. TAKE PICTURES OR WRITE DOWN WHERE EVERYTHING GOES!! Unless you have the time to do this start-to-finish in one day (and even if you do...), you'll never remember it all.

Once it's all back together, your lights will be at their normal luminosity, the wipers will be back to their lazy lope and your ECU and Blaupunkt radio will breath a sigh of relief and thank you for your efforts.
- Dick

1970 Transporter. 2015cc, dual Weber IDF 40's
1978 Riviera Camper. Bone stock GE 2.0L F.I.
1979 Super Beetle convertible.

... as it turns out, it was the coil!

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Amskeptic
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Re: Replacing The Voltage Regulator In A Fuel Injected Beetl

Post by Amskeptic » Mon Feb 28, 2011 7:39 pm

dtrumbo wrote:So you're driving along Aliens?
No, you'll never remember.
Remember what? :alien:

Nice write-up.
ColinOnThePatioOfThis*****HotelSippingMintJulepsWhileWatchingHisMinionsRenderHimObsolete
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

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Re: Replacing The Voltage Regulator In A Fuel Injected Beetl

Post by Jeanpierre » Wed Mar 19, 2014 12:15 am

This is a wrong Way ,,originaly there are 4 screws In the back of the fan box ..1 of these is impossible to remove without removing the engine,,

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Re: Replacing The Voltage Regulator In A Fuel Injected Beetl

Post by asiab3 » Wed Mar 19, 2014 10:29 am

Excellent write-up. I'm glad you pointed out the 3 screws on the backing plate instead of four. A friend of mine runs his early bay like that on purpose, so when his AutoBone alternator craps out he can change it in the car without pulling the engine, since the missing screw is the only one that can't be accessed with the engine assembled. With the three screws loose you can theoretically remove the alternator with the fan without lifting the shroud.

Jeanpierre wrote:This is a wrong Way ,,originaly there are 4 screws In the back of the fan box ..1 of these is impossible to remove without removing the engine,,
I'm not sure what you mean- I know the OP said this:
loosen the two screws on the bottom of the left and right side of the fan shroud.
And I have those screws and one more in the back by the doghosue ducting, but 4? Where?
1969 bus, "Buddy."
119k miles with me.
296k miles on Earth.

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Re: Replacing The Voltage Regulator In A Fuel Injected Beetl

Post by Amskeptic » Fri Mar 21, 2014 12:02 pm

asiab3 wrote:Excellent write-up. I'm glad you pointed out the 3 screws on the backing plate instead of four. A friend of mine runs his early bay like that on purpose, so when his AutoBone alternator craps out he can change it in the car without pulling the engine, since the missing screw is the only one that can't be accessed with the engine assembled. With the three screws loose you can theoretically remove the alternator with the fan without lifting the shroud.

Jeanpierre wrote:This is a wrong Way ,,originaly there are 4 screws In the back of the fan box ..1 of these is impossible to remove without removing the engine,,
I'm not sure what you mean- I know the OP said this:
loosen the two screws on the bottom of the left and right side of the fan shroud.
And I have those screws and one more in the back by the doghosue ducting, but 4? Where?
Shoot a PM to dtrumbo. I think JeanPierre was talking about the four 10mm bolts that hold the fan cover plate to the fan housing.
The two screws at the bottom of the left and right sides attach the housing to the cylinder covers.
Colin
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

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Re: Replacing The Voltage Regulator In A Fuel Injected Beetl

Post by asiab3 » Fri Mar 21, 2014 1:30 pm

Amskeptic wrote:Shoot a PM to dtrumbo. I think JeanPierre was talking about the four 10mm bolts that hold the fan cover plate to the fan housing.
The two screws at the bottom of the left and right sides attach the housing to the cylinder covers.
Colin

Ah yes- back is back of car. :silent:
1969 bus, "Buddy."
119k miles with me.
296k miles on Earth.

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Re: Replacing The Voltage Regulator In A Fuel Injected Beetle

Post by ainokea » Fri Mar 11, 2016 12:36 am

Would it not be easier to remove the ancillaries, air box, boot, manifold center, alt. hold down strap, etc. etc. and once clear, remove the fan in back of the alternator, then the 4, 10mm backing plate bolts, allowing the alternator to be removed from the shroud without the fan. The deck lid and brackets stays put and so does the fan shroud, especially efficient if it's a dog house shroud. Ainokea

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Re: Replacing The Voltage Regulator In A Fuel Injected Beetle

Post by Amskeptic » Tue Mar 22, 2016 7:48 pm

ainokea wrote:Would it not be easier to remove the ancillaries, air box, boot, manifold center, alt. hold down strap, etc. etc. and once clear, remove the fan in back of the alternator, then the 4, 10mm backing plate bolts, allowing the alternator to be removed from the shroud without the fan. The deck lid and brackets stays put and so does the fan shroud, especially efficient if it's a dog house shroud. Ainokea
Due to the very close tolerance required between the fan and the mounting plate, I recommend removing fan and alternator assembly as a unit. Then you can see the current tolerance, the current run-out, the current number of fan shims used to get the current tolerance, and you will have much better control over assembly torque and quality of work checks.

If you have an older oily engine, I recommend that you remove the entire fan housing and clean and replace cooler seals while you are there.
Colin
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

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Re: Replacing The Voltage Regulator In A Fuel Injected Beetle

Post by kreemoweet » Tue Mar 22, 2016 9:48 pm

It was good to mention replacing the bearings while the alt was out and accessible, but the same could have been said for the slip rings. The rings
in the tutorial above are clearly very worn, and it is evident just how thin the copper in that area is. It would be a shame to have to pull the alt
again 8 months later because of a failure there. If that were my alt, I'd take it to a shop to have the rings machined, if possible. I'm pretty sure
the minimum ring diameter is 27.3 mm (VW spec for very similar 50A alternator used on busses). New slip ring assemblies are available.

Bosch regulators for these alts are getting very difficult to find. There's a Chinese unit available that incorporates the regulator and brush
assembly into a single unit (Transpo #IB003-2684-12V). With that, one could just snip the old regulator wires and abandon in place - no alt
removal necessary. I've got one, and I intend to try it out when my current newish alt fails in 15 years or so. I also see no reason why the
alt could not be modified so the stock regulator could be mounted externally in some fashion.

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Re: Replacing The Voltage Regulator In A Fuel Injected Beetle

Post by Amskeptic » Wed Mar 23, 2016 6:51 pm

kreemoweet wrote: New slip ring assemblies are available.
Where? Where? I need some.
Colin
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

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Re: Replacing The Voltage Regulator In A Fuel Injected Beetle

Post by kreemoweet » Wed Mar 23, 2016 8:53 pm

Amskeptic wrote: I need some.
I got mine from these guys: http://www.aspwholesale.com/slip-ring-bo-p919.html
They're cheap! If I was younger, I would've gotten a dozen or so.
They also have a number of (non-Bosch) replacement parts for the AL-82 style alternators, and for the other Bosch alts VW used, I'd wager.
It helps to have the long Bosch number to search for parts there.

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Re: Replacing The Voltage Regulator In A Fuel Injected Beetle

Post by SlowLane » Wed Mar 23, 2016 9:00 pm

kreemoweet wrote:
Amskeptic wrote: I need some.
I got mine from these guys: http://www.aspwholesale.com/slip-ring-bo-p919.html
They're cheap! If I was younger, I would've gotten a dozen or so.
They also have a number of (non-Bosch) replacement parts for the AL-82 style alternators, and for the other Bosch alts VW used, I'd wager.
It helps to have the long Bosch number to search for parts there.
I also bought some slip rings, bearings and a "heavy duty" diode assembly for my alternator from ASP. The slip rings seem to be decent. The bearings so-so, the diode assy cheap and flimsy. Transpo is the brand. Chinese, naturally.
'81 Canadian Westfalia (2.0L, manual), now Californiated

"They say a little knowledge is a dangerous thing, but it is not one half so bad as a lot of ignorance."
- Terry Pratchett

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Re: Replacing The Voltage Regulator In A Fuel Injected Beetle

Post by ainokea » Fri Apr 01, 2016 8:07 pm

Without meaning to sound contrary, I have to say that I have done this job a number of times on EFI bugs, standards with generator or alternator, as described in my previous post above. I do agree that if you're doing this at home, time is of no great significance, unless the job at hand has to be completed as quick as can be done, but in a shop environment where time is money, the job has to be done right and in a given time span. I personally never had a problem with fan shims or removing the fan nut with the device installed. Never had occasion to remove the fan shroud unless an oil cooler leak was discovered or a purely funky engine was hiding under the shroud. The shop I was employed at did not stress the book time and allowed us to deal with unexpected problems that popped up every now and then. But, they did expect a completed job in a reasonable time. Doing a job at home is great without having to watch for the boss if you want to grab a cup of coffee or just stop and shoot the bull with friends or neighbors. Only setback is no paycheck at weeks end.

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Re: Replacing The Voltage Regulator In A Fuel Injected Beetle

Post by Amskeptic » Sat Apr 02, 2016 7:01 am

ainokea wrote:Without meaning to sound contrary, I have to say that I have done this job a number of times on EFI bugs, I personally never had a problem with fan shims or removing the fan nut with the device installed. Never had occasion to remove the fan shroud unless an oil cooler leak was discovered or a purely funky engine was hiding under the shroud.
The question, however, is if you have ever disturbed the bearings or replaced the generator/alternator, how did you set the fan spacing?

I will not run a VW Type 1 without guaranteeing to myself that the fan has acceptably low run-out and is no more than 2mm from the support plate.
Colin
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

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Re: Replacing The Voltage Regulator In A Fuel Injected Beetle

Post by ainokea » Sat Apr 02, 2016 2:09 pm

First the 36mm nut is removed, then the 4 backing plate bolts and hold down strap are removed, next, the alt. or gen. is pulled out far enough so the fan can be seperated from the gen. or alt.. It remains in the shroud allowing the al;t. or gen. to be removed. Once the gen. or alt. is out, the fan can be pulled out and from there it's easy enough to set the fan to backing plate clearances before re-installation. The only tricky part is re-installing the washer and nut and torquing it to 43 ft. lbs. To enable removal and installation of the 36mm nut, the rear half of the pulley must be in place with the proper woodruff key. A 21 or 21mm open end, I forget which, will fit the pulley squares and hold it firm for torque and removal Ainokea

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