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Sat Dec 19, 2020 1:09 pm

catbox wrote: vintage dubs wrote: I like all the nice brackets. I bought my wife a square at the end of last year and started looking into the conversion. Not many inexpensive choices out there. As luck would have it the generator took a sh** so I was forced to make a move pretty quick. So I found a Geo metro at the pull a part and took off the alternator. I also took both mounting brackets. When I got home I realized that the double ear mounting bracket would work perfectly. I set up everything and redrilled the bottom hole on the the double ear bracket where i needed it to be and I was good to go. Trimmed the engine tin slightly. An alternator shop had the pulley.Long story short $35 and 2 hours of my time and everything works perfectly :D

Out with the old!!

This is just an alternative. The kits out there are very nice. If you don't want to trim your shroud or have a show car this may not be for you. This is my wife's car for her photography business so she didn't mind she just wanted to get back on the road :)

http://www.facebook.com/trulyvintagephotography

"Penelope"

http://www.vintagewagens.com/

I just re-read this whole thread to see where the progress ended.

I would say that the above is the way to go for me.
I am heading to the junkyard soon and will be picking up a set of the Geo brackets when we are there.
I already have a 3 cylinder and a 4 cylinder alternator from when there was a 50% off the whole yard sale.

One of these days I will get back to work on my square.
Get yours running, as we want to see it at the Woodburn Bug Drags! 8)

Mon Dec 21, 2020 11:35 am

That is the plan.
I took a break from all things VW for a while.
I have since found my mojo and am slowly getting back to it.

First up is building the engine for the square and then stabbing it back together.
It has been living in the garage as a storage shelf for the last couple of years.

Fri Jan 01, 2021 11:49 am

I've been contemplating an alternator conversion for a while. I found a bug alternator in my stash of parts. Looking thru the pages, it looks like I can cut and grind the housing and not require any tin modifications? Can anyone that's done this confirm? Thanks!

Fri Jan 01, 2021 12:34 pm

Yes, type 1 conversions have been done, a few times here.

Fri Jan 01, 2021 2:52 pm

Roadbeater wrote: I've been contemplating an alternator conversion for a while. I found a bug alternator in my stash of parts. Looking thru the pages, it looks like I can cut and grind the housing and not require any tin modifications? Can anyone that's done this confirm? Thanks! I posted a thread with pictures of what/where to grind down to make it fit properly.

Fri Jan 01, 2021 3:56 pm

oxsign wrote: Roadbeater wrote: I've been contemplating an alternator conversion for a while. I found a bug alternator in my stash of parts. Looking thru the pages, it looks like I can cut and grind the housing and not require any tin modifications? Can anyone that's done this confirm? Thanks! I posted a thread with pictures of what/where to grind down to make it fit properly.

I saw your post, that's the only one that I could find that successfully installed without cutting the tin. I'd much rather hack on a Type 1 alternator than Type III tin. Thanks for the confirmation!

Fri Jan 01, 2021 9:39 pm

Roadbeater wrote: oxsign wrote: Roadbeater wrote: I've been contemplating an alternator conversion for a while. I found a bug alternator in my stash of parts. Looking thru the pages, it looks like I can cut and grind the housing and not require any tin modifications? Can anyone that's done this confirm? Thanks! I posted a thread with pictures of what/where to grind down to make it fit properly.

I saw your post, that's the only one that I could find that successfully installed without cutting the tin. I'd much rather hack on a Type 1 alternator than Type III tin. Thanks for the confirmation!
There have been a few done, and a search should bring up a few threads of going with a bug alternator.

Sun Jan 03, 2021 3:15 am

Has anyone modified the fan pulley to accept a multi-rib belt pulley? Kinda like turning the fan pulley into a hub that a multi rib pulley can bolt to.
I've got an idea that involves using a multi-rib fan belt and matching alternator pulley but the fan pulley needs more thought.
Those original vee belt fan pulleys are getting harder to find in good condition.
When I was searching for a decent one I tossed maybe 6 or 7 worn out pulleys in the wrecking yard stock.

Sun Jan 03, 2021 5:13 am

I played around with one for a Type 4 fan but the Type 3 fan is more difficult. The diameter is so much larger, it is difficult to source a donor. But you can machine a pulley ring from scratch, it's just more work

Sun Jan 03, 2021 1:25 pm

I might have to visit the wrecking yard and see if they'll give me a worn out pulley to experiment with.

Sun Jan 30, 2022 1:07 pm

Revisiting this thread. Is there a kit or someone who fabricates brackets to fit a geo metro alternator? I have a 67 square. I don’t want to cut things but I need more power than 55 amps that the kits available online offer.

Mon Jan 31, 2022 10:04 pm

I'm starting on my alternator conversion and just re-read the thread, also.

I'm also hoping for something more than 55-60 amps, and had been on the lookout for something that fits and has a larger output. I ended up ordering this alternator - it's for a Toyota Landcruiser and possibly a little bit too large but claims 120 amps and juuust fits under the decklid so I'll be giving it a whirl.

The biggest doubt I have is that the original application is a 4.5L diesel engine and I wonder if I'm gonna be lacking enough torque to rotate the thing. A cursory look online makes me think I'm going to be okay but I'll admit that I know very little about the finer details of electrical stuff.

It will also need some mods to the pulley tin, which might be a bit controversial but I have a really beat up tin which I'll modify instead of cutting this nice one.

Sun Feb 13, 2022 4:38 am

Today I worked on the right side bracket for my alternator. The slightly larger size means I had to locate it a little higher and to the left from where the stock generator sits. The location I settled on clears the distributor (just) and will allow for 5-10mm of adjustment.

Another quirk of this setup is that the post for the main wire ends up at the bottom of the alternator - I had to make sure there was no chance it would ground out against the fan shroud or engine tin. I couldn't get a photograph, but the post is at the front to the lower right near the distributor and has sufficient clearance (5-10mm) all around and I'm hoping access with a spanner will not be too painful..

I'm hoping to make the left side bracket over the next week or two.

Sun Feb 13, 2022 12:43 pm

really-whale wrote:
The biggest doubt I have is that the original application is a 4.5L diesel engine and I wonder if I'm gonna be lacking enough torque to rotate the thing.

The torque it takes to rotate it is 100% dependent on how much current you pull from it. :D

Just doing some rough math with internet calculators and imagining that everything is 100% efficient,

120A at let's say 14v = 1680 watts of power.

Of course an alternator doesn't produce max current at all times, it simply produces what is being drawn by the electrical system up to its max output of 120A.

But let's say for the sake of argument you were pulling a steady 1680 watt load on the car's electrical system and the alternator was maxed out. Maybe you're powering a microwave oven via an inverter inside the car to heat up your burrito.

Well 1 hp = 746 watts, so 1680 watts would consume 2.25 hp to drive the alternator.

hp is merely a value calculated via formula from the factors of torque and rpm.

HP = (Torque (lb ft) * RPM) / 5252

So re-jigger the equation to solve for torque...and then you have to specify at what rpm so you would need to know the pulley ratio of the alternator pulley vs. the crank pulley, but let's just say for purpose of the example that the alternator pulley is spinning at 2000 rpm.

Torque = 2.25 hp / 2000 rpm * 5252

So it would take about 6 ft-lbs. of torque to spin the alternator at max output assuming alternator pulley rpm was 2000 rpm. As alternator speed goes up, the torque required goes down.

So I would say wait until you are above idle to microwave your burrito.

Sun Feb 13, 2022 1:26 pm

sjbartnik wrote:
So it would take about 6 ft-lbs. of torque to spin the alternator at max output assuming alternator pulley rpm was 2000 rpm. As alternator speed goes up, the torque required goes down.

So I would say wait until you are above idle to microwave your burrito.

Thanks for the explanation, that makes sense. Seems like it will be okay for my application - although I do like the idea of highway burritos too :lol:

Sun Feb 13, 2022 7:29 pm

Just out of interest, why do you feel the need to run a 120 amp alternator ?
I am not an electrician by any means, so really struggle to understand all this, but I have worked out that with everything swtiched on in my Fastback, the approximate draw would be about 28.3 amps, and that is lights, wipers, garmin, iphone charging, radio on, etc etc etc.
I am still running the original generator,and it shows full voltage when I am on the road and almost everything is switched on. I have been considering a (much smaller) alternator upgrade for a while, but at the moment just don't see why I need to spend that money - As long as the generator keeps working, of course !
I am fitting a second deep cycle battery into the pax side under the rear seat, and fitting a DCDC charger there to keep it charged when I am on the road round Australia in about 6 weeks time. From this battery I am going to run my small fridge and external lights at night when I am camping, so they don't drain the main battery.
When we took the 1954 Healey across China in 2019, we ran all sorts of navigation equipment, along with phones, ipads etc, and had to drive with lights on all the way. We installed a 75 Amp alternator, and never got close to extending it.
So what are you going to run that needs so much amperage ? Or does "spare amperage" equate to "better reliability" ?
Appreciate any insight so I can make sure my trip goes without any amperage hitches !!
Thanks,
Giles

Sun Feb 13, 2022 8:32 pm

I don't plan on using all 120A really, when I purchased the alternator it was purely due to price and that the form factor looked promising. I had been looking for the commonly swapped alts online and the Land Cruiser alt worked out ~$100 aud cheaper for me. My existing generator needed some serious care although it is something I would like to recondition at some point.

Your trip around Australia sounds awesome! I would love to take mine on some longer camping trips once it is back on the road.