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ChrisFrost Sat Mar 10, 2007 8:18 pm

Just bought. How do I know what I have...a Thing with an alternator or one with a generator? Thanks.

uberautowerks Sat Mar 10, 2007 10:35 pm

Things were originally equipped with generators, however, it's not uncommon to see alternators under the "Hood".
A generator is shaped like a simple tube, the size of the pulley, with to bolts sticking out of the top for the wiring. While an alternator is more complex looking, larger in diameter than the pulley and had at least on push on wire connector.

Ian Epperson Sun Mar 11, 2007 3:07 pm

Generator:


Alternator:

90runner Mon Mar 12, 2007 4:23 pm

I there extra wiring reqired for the alternator having a internal voltage reg?

Ian Epperson Mon Mar 12, 2007 5:35 pm

Whe you install an alternator, you've got to bypass the external regulator. You've got to cut some wires, re-route them and crimp on a different connector. It's not too hard to do.

All in all, it cuts down on the wires in the engine compartment.

Of course you get a lot more power from the alternator though. For those that don't know, a generator makes more voltage the faster it goes and the regulator disconnects the gen from the battery when it makes less voltage than the battery. If it didn't, the gen would act as a motor, pulling juice from the battery to try and turn the engine. If you put a voltmeter on the generator, you'll see the voltage rise and fall with the engine speed. When the voltage falls below about 12v, the regulator disconnects it. This means that at idle, the generator isn't doing anything and the battery is slowly discharging. Sometimes you can see this at night - the headlights suddenly dim at idle, then brighten as you rev.

An alternator always makes the proper voltage and varies the amperage by varying the internal resistance. If you put a voltmeter on the alternator, it will always say about 13.5 volts no matter how fast or slow it spins (as long as it spins). At idle, it's still charging the battery, just at a much lower rate. Since the voltage is always the same, the headlights are always the same brightness.

It's a cleaver piece of engineering. In a generator, you've got spinning magnets - as they spin past a coil they make electricity. The more powerful the magnet or the faster you spin it, the more juice you get. In an alternator, the spinning magnets are replaced by a spinning electromagnet. As an alternator slows down, the electomagnet gets more power (stronger magnet) so that it pushes the same amount of electrons as it was when it was spinning fast. As it spins faster, the electromagnet gets weaker to keep everything balanced out. This also means that there must be at least SOME energy in the battery before it will make electricity - an alternator can't set up the electromagnetic field without some initial voltage. So if your battery is FLAT or you've removed it, you won't be able to push-start the car. Even if the battery is "dead" it will usually still make enough juice for the alternator.

Woreign Mon Mar 12, 2007 8:24 pm

Ian,

Great description! I think I even learned something...

surferdudedav Wed Mar 14, 2007 7:58 pm

anybody got a alternator for sale?>?

bucko Wed Mar 14, 2007 8:30 pm

Any of the major VWdub aftermarket vendors sell a kit. You'll have to change the tower as well. The generator towers are different from the alternator towers. The kits come with both pieces. You may also need to change the fuel pumps, as earlier pumps hit the alternator. Later fuel pumps are shorter, and angle to the right.

Also, on our beloved Things, it's darn near impossible to remove the old generator/fan assembly with the engine installed. Easy on Beetles though.

You'd need to remove the two side fan shroud screws in order to lift the fan shroud so that the 4 fan box screws, generator strap, generator wires (and don't forget to disconnect the thermostat rod to the "flappers) can be removed. The dual port intake boot (right side) needs to be removed along with the right side intake I believe as well. Then you can remove the fan box/generator from the fan shroud.

Problem is, the fan shroud cannot be lifted up enough in the engine compartment to clear everything.

If the engine is out, piece of cake.

surferdudedav Thu Mar 15, 2007 4:59 am

bucko wrote: Any of the major VWdub aftermarket vendors sell a kit. You'll have to change the tower as well. The generator towers are different from the alternator towers. The kits come with both pieces. You may also need to change the fuel pumps, as earlier pumps hit the alternator. Later fuel pumps are shorter, and angle to the right.

Also, on our beloved Things, it's darn near impossible to remove the old generator/fan assembly with the engine installed. Easy on Beetles though.

You'd need to remove the two side fan shroud screws in order to lift the fan shroud so that the 4 fan box screws, generator strap, generator wires (and don't forget to disconnect the thermostat rod to the "flappers) can be removed. The dual port intake boot (right side) needs to be removed along with the right side intake I believe as well. Then you can remove the fan box/generator from the fan shroud.

Problem is, the fan shroud cannot be lifted up enough in the engine compartment to clear everything.

If the engine is out, piece of cake.

THANKS!

Captain Spalding Thu Mar 15, 2007 1:48 pm

Ian Epperson wrote: This also means that there must be at least SOME energy in the battery before it will make electricity - an alternator can't set up the electromagnetic field without some initial voltage. So if your battery is FLAT or you've removed it, you won't be able to push-start the car. Even if the battery is "dead" it will usually still make enough juice for the alternator.
Does that mean that even if I have an alternator, my car could still be a candidate for hand cranking?

bucko Thu Mar 15, 2007 5:26 pm

Captain Spalding wrote: Ian Epperson wrote: This also means that there must be at least SOME energy in the battery before it will make electricity - an alternator can't set up the electromagnetic field without some initial voltage. So if your battery is FLAT or you've removed it, you won't be able to push-start the car. Even if the battery is "dead" it will usually still make enough juice for the alternator.
Does that mean that even if I have an alternator, my car could still be a candidate for hand cranking?

Or pushing....

I don't see either in you and your Things future though; too nice an example.

Fun 181 Thu Mar 15, 2007 5:57 pm

Does anyone know if there is an aftermarket or OEM cap (or boot) that covers the wire terminal on top of the alternator? It sure does set off a real nice spark if you hit it by accident. Doh!

I've seen rubber boots for the generator terminal, but I'm not sure if they will fit an alternator. I thought I had seen an aftermarket cover (insulated billet?) once, but haven't been able to find anything since.

alg Thu Mar 15, 2007 6:41 pm

Alternator wire covers are available at most online bug part places.
(GMW, jBugs, MidAmerica, etc)

eis just chimed in with these parts, and there is a cover available:
http://eisparts.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=EIS&Category_Code=thing

Fun 181 Thu Mar 15, 2007 10:15 pm

I've searched MidAmerica, Moore, SoCal, Jbugs, CIP1 and others (like the above link) and can not find any alternator wire covers/boots.

I found generator boots at each supplier, but nothing for alternators.

Will a generator boot fit on the alternator terminal? It doesn't look like it will.

Ian Epperson Fri Mar 16, 2007 10:27 am

Fun 181 wrote: Will a generator boot fit on the alternator terminal? It doesn't look like it will.

I believe it will fit.

Talosian Thu Jul 23, 2009 8:15 am

bucko wrote: Any of the major VWdub aftermarket vendors sell a kit. You'll have to change the tower as well. The generator towers are different from the alternator towers. The kits come with both pieces. You may also need to change the fuel pumps, as earlier pumps hit the alternator. Later fuel pumps are shorter, and angle to the right.

Also, on our beloved Things, it's darn near impossible to remove the old generator/fan assembly with the engine installed. Easy on Beetles though.

You'd need to remove the two side fan shroud screws in order to lift the fan shroud so that the 4 fan box screws, generator strap, generator wires (and don't forget to disconnect the thermostat rod to the "flappers) can be removed. The dual port intake boot (right side) needs to be removed along with the right side intake I believe as well. Then you can remove the fan box/generator from the fan shroud.

Problem is, the fan shroud cannot be lifted up enough in the engine compartment to clear everything.

If the engine is out, piece of cake.

It looks like we're talking a pretty major process changing from a generator to an alternator; new stand and changing the fuel pump (mine is a 1971 Safari/Thing).

Maybe best left to a good mechanic, but don't know about getting parts here in Mexico.

Anyone ever use an alternator from other than a VW/Thing?

Thanks.

Ian Epperson Mon Aug 03, 2009 2:19 pm

Clearing the shroud is the tough part. Beyond that, it's just bolting on parts and reworking wiring. If you can drop your engine, you can probably do it without issue.

Putting a non-VW alternator in a Thing? THAT'S work. Custom built bracket, custom built backing tin, custom built pulley system, reworking the alternator to also turn the cooling fan, etc.

uberautowerks Mon Aug 03, 2009 2:34 pm

Let me give you all a tip that makes getting a generator or alternator out of our VW's, Things and beetles, heck even busses.

Use a 36mm socket and a longish breaker bar to remove the nut holding the fan to the generator. You know the one around the back? Leave the pulley on use a screwdriver to hold the pulley(as you would while changing the belt).
Once the nut is off, and it's washer, you'll have a lot easier time removing the generator and backing plate. Leave the fan in the shroud then reattatch when reinstalling the generator.
With this tip you don't need to remove or move the intake nor do you have to remove the shroud. You may still need to lift the shroud up a bit to get to the bottom two backing plate bolts, but you only need to lift it an inch or so.

DougD Tue Nov 22, 2011 12:50 pm

So this is an old thread but I didnt want to get the classic "do a search this has been covered response" so I thought this would be an appropriate location for a generator/alternator question...

I have a generator and although I have no doubt I could handle the conversion to an alternator its about half of the way down on my to-do list. So the question is in your experience how much power can a generator support for a radio? I dont have one now but I would like to put one in. I'm thinking something basic with four low powered(25-50w) speakers. I just want some basic tunes but I also dont want to kill the generator/battery to do it... you think I'll have any problems? I'm thinking the main problem would be at idle/no charge but I was thinking I might just put in a capacitor to handle the charging peaks/lows. Thanks!

joescoolcustoms Tue Nov 22, 2011 1:09 pm

I ran 100 W radio/amps off of a generator with no problems when I was in school. I did travel a 1 hour to school each way every day so the battery did get proper charge.



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