12V Generator W/ Briggs & Stratton Engine

[Texasflyboy]

I'll try and update this post later with more info and details, but here is the main info.

I saw the below generator setup years ago on the net and always wanted to have one. Why? Dunno. Maybe because I like the idea of using old parts that I have lying around to make stuff. See my other post regarding a really big casting pot. :-D

Here is what got me started:

http://users2.ev1.net/~eastus1/a/generator3.jpg

I went ahead and built one exactly like it, only to realize right at the end of the project that a B&S engine spins counterclockwise when looking at the shaft, and car engines turn clockwise. So, in the above setup, their alternator spins backward.

Ain't gonna happen here....nope, no-way, no-how.

So, I trashed the mount I made out of aluminum and made a Z bracket that faced the alternator towards the B&S engine. Made it out of 1/4" plate and stuff l had lying around the house and work. Here is my design, with the alternator spinning the correct way:

http://users2.ev1.net/~eastus1/a/generator2.jpg

Click the link for a larger photo:

Larger Photo (http://users2.ev1.net/~eastus1/a/generator.jpg)

And here is a little 5MB Quicktime movie of it running:

Clicking this link will open the Quicktime Movie (about 5MB) (http://users2.ev1.net/~eastus1/a/generator.mov)


Anyway, I had an old Chevy alternator (a big 93amp), a 12V car battery bought for hurricane season, and stumbled into a brand new 127cc (~3hp) Sideshaft B&S engine that was NIB, but over 15 years old. Got it trading a Harbor Frieght Mig Wire 110V welder that I never could find a use for. All in all I have about $35 in this thing. Most of the parts were this and that left over from other projects. The red marker light was in a kit from a trailer re-wire years ago, didn't need it. So I put it on for red illumination for night work when we're fishing and don't want to lose our night vision. The white light was an old courtesy light leftover from my hot rod days. The switches were picked up over the years and the wiring, well, who doesn't have oodles of old wiring in the garage? I think I had to buy the battery cables and the little 12V cigarette socket, the fan belt, and the engine pulley. That's about it. Took about 4 days of fiddling around to make this thing and it runs like a champ. I plan to put wheels under the platform and cover it with a thin plywood box to weatherproof it.

It's just a neat little project that anyone can do, and you end up with a portable 12V charging system that is handy as heck to have around.

More details if anyone is interested.

12.06.06 Edit

As many folks have pointed out, which way the alternator spins is irrelevant for making electricity. But, me, I'm a worry wart. I worry that the alternator blades, which are designed to pull air from the rear of the case for cooling would not work, or work as well, if the pulley were spinning in the wrong direction. It probably wouldn't kill it to run backward, but with my luck, the exact moment the alternator would decide to die would be the most inopportune time in all of known history. That's just my luck...:-D So that's why I made the Z bracket to have it face the engine to spin the correct way.

[floodgate]

Flyboy:

(Are you perchance involved with the Confederate Air Force???)

Neat setup! A local shearer gave me the power unit, support bracket and drive clutch for a sheep-shearing machine powered by a little 1-1/2 Hp (2" bore and stroke) side-valve B&S motor from 1947 (per the serial number). Exhaust valve was lightly stuck, but got it free, and innards look OK. Now I've got to ask around and find one of the articulated shearing drives and a shearing head for it. Our little flock of Shetlands had better look out!

floodgate

[Dark Helmet]

Another way of doing it is to hang an alternator under the deck of a pushmower- then you already have wheels and a handle!

[slughammer]

Do you need the battery? I've got a 3hp Briggs, a Ford alternator and a voltage regulator around here somewhere.

[Texasflyboy]

Yes, from what I understand, you do need the battery. It takes a small amount of electricity to "excite" the alternator to produce electricity, which the battery provides.

[Texasflyboy]

Another way of doing it is to hang an alternator under the deck of a pushmower- then you already have wheels and a handle!

Yep, the place I read about these even has a special bracket to do this, but I still think that spinning the alternator the correct way is the best way to go long term. B&S engines spin counterclockwise, and alternators need to spin clockwise, so they have to face each other.

[Buckshot]

..............Very clean setup. I've seen those before. When I was a kid a neighbor made a small arc welder using a setup like that. I don't know what HP engine he used or if it was a B&S,Tecumsh, Clinton or what. I know that when he 'stuck' one of his coathanger electrodes it'd make that little engine hunker down and bark :-)

...............Bucksot

[Ricochet]

I don't think the alternator gives a rat which way it turns.

[dragonrider]

Do you have a voltage regulator in that setup somewhere, or is it not needed.?

[scrapcan]

I think you can also use one of the new self exciting alternators, not sure which brands they are but they are out there. I do not know if the larger amperage units can be self exciting? Someone else will have to answer that question.

Also if you use a delco internal regulator type alternator (1 wire) you do away with the need for a voltage regulator. You lose the ability to have your own set points that you would have if you used a mechanical type regulator.

You might also need to check ratio on pulleys to make sure you are turning it at a proper speed for best performance.

Pretty cool project and I would be pleased if you dropped it off in my driveway.

[BeeMan]

Direction of rotation shouldn't matter to bearings, windings, or brushes. It might reduce cooling if there is an internal fan or other directional airflow. That said, I doubt any standalone application will come near the underhood temperatures of a modern car.

I've got the pieces to do the 12V side, but really want to include a good sine wave inverter and battery bank to run several KW of AC loads. A 5KW generator is too noisy when run continuously during long power outages (hurricanes.)

BeeMan

[PatMarlin]

I'm totally Off-the grid solar, and what do I use for back up generator?... You got it..
DELCO!!.. :mrgreen:

Normally,

People with solar systems go out and buy a big generator. Like a 15,000 watt kohler or something, and they cost big bucks. Most are real hard on gas, but the more efficient diesels are more money, and the ones that are made for hard use cost even more.

I came up with a dual approach. This is my main charging generator. This baby handles it all.

It's a Yanmar 6 hp diesel driving a Chevy alternator. It kicks out 35 amps, directly to the battery bank via big copper cable, at a run of about 100 feet away from the house. It will run about 6 hrs per tankfull, and that tank holds LESS than a gallon of fuel.

35 amps is a hunka power that will fully charge the battery bank with a tank full, or less depending on what you need. It's pretty darn quiet too!

That's some cheap energy... plus it's a Chevy alternator, why wear out a big expensive generator?

[scrapcan]

PatMarlin,

Tell me more aobut your small diesel. Are you running the L70V? Where did you get it? What did it Cost? How does it do in cold weather? have you tried it with HomeBrew Biodiesel?

Sorry about the 20 question game, but I wan to build a generator like you have done.

Jeremy

[Dark Helmet]

Ooh that's neat!

[Texasflyboy]

(Are you perchance involved with the Confederate Air Force???)

LOL. God no. I wish tho! If I was I would pick the Douglas A-26 as my ride tho!

Zowie!

http://www.warbirdalley.com/images/A-26-1-Lady-Liberty.jpg

[Texasflyboy]

You might also need to check ratio on pulleys to make sure you are turning it at a proper speed for best performance.

I did. And checked the math. The pulley on the B&S engine matches the 77 Pontiac drive pulley that this alternator was one of the options for.


Pretty cool project and I would be pleased if you dropped it off in my driveway.

LOL. Sure. I'll have Santa drop it off at your place just as soon as he unloads my new 1050 from Mike Dillon....;-)

[Texasflyboy]

Do you have a voltage regulator in that setup somewhere, or is it not needed.?

It's a 12SI style internally regulated AC Delco alternator. Zillions around.

[Ricochet]

Ooooh, I love that A-26, later renamed B-26! When I was a kid I saw one of those at the airport being used as a borate bomber for firefighting. Struck up a conversation with the pilot, and he let me climb all over that thing and sit in the cockpit! Later I found one of the converted business plane versions built by On-Mark Engineering in a general aviation hanger at the Birmingham Airport in 1976. I gave it a good walk-around inspection, but didn't get inside.

[PatMarlin]

PatMarlin,

Tell me more aobut your small diesel. Are you running the L70V? Where did you get it? What did it Cost? How does it do in cold weather? have you tried it with HomeBrew Biodiesel?

Sorry about the 20 question game, but I wan to build a generator like you have done.

Jeremy

Jeremy,

It's an L70AE (angle eject.. :mrgreen:), and I bought it through a freinds company bout' 7 years ago. Cold weather doesn't bother it much. They are crazy expensive now, but there are Chinese knock offs on the market now.

In fact, I screwed up and didn't get electric start on this one as my wife doesn't have the upper body strength to start it, but I picked up a chinese copy with electric start for peanuts here:

http://www.zjig.com/

http://www.marketworks.com/storefrontprofiles/gallery.aspx?sfid=84166

I haven't ran bio diesel in it cause we don't have a restraunt in our area that DOESN't use hydrogenated oil. You need to run a pure oil becasue that crap waxes, and ruins IP's and the inside of metal tanks and lines.

[Buckshot]

...................:hijack:..................

Ricochet, I don't know if I was confused by your post or not, but the B-26 was designed and built by Martin Aviation. I do believe that it's roll in the European theater was partially taken over by the Douglas A-26. I also think you're right that they also re-named it the B-26 later on after the war, as that seems familiar.

The Martin B-26 and the Chance-Vought F4U Corsair were the 2 WW2 aircraft that most fascinated me. While the Martin B-26 was badmouthed as a tough plane to takeoff in and land it had the lowest attrition rate of any bomber in the war. It was also faster then it's spec sheet called for (about 290 MPH), many easily exceeded 315 MPH in level flight. If it had any altitude and found fighters after it, put into a few degrees of downangle it could pick up another 25-30 mph. Usually this only allowed fighters one or two passes before the plane was over friendly ground.

It seems a shame, but the military was quick to be rid of them even before the war was over. Many squadrons transitioned into the A-26 and the B-26's were junked.

...............Buckshot

[toecutter]

I don't know much about self exciting coils, but it really doesn't take much to get a coil going. If you were to take a 12v lead acid cell (one of the small 5Ah) you could easily excite the coil, and still generate all the power you need. I've been meaning to build one of these for a while now, but I havn't had time to futz with the little engine I've got. (really old B&S I found in a neighbors trash).

A few years ago my little brother built a bicycle thing that was powered by a 2 cycle weed wacker motor. His drive system was rather primative, so you killed the engine when you stopped, and started it up again just by pushing the bike forward. I was kinda thinking about trying an electric start that was similar, maybe use a compressor motor (or even a starter motor) to jump start it, and then put in some autostart/autokill features. i.e. when batteries are at 60% start engine run until batteries are at 90%.

What a fun project!

[scrapcan]

texasFlyboy,

good to hear someon has already done the math. What size pulley did you use on the B&S? You are right on the alternator you used. Easy to come by and easy to rebuild if necessary. My wife had an 88 GMC pickup when we got marrie dan dit ate alternator bearings like crazy, 6 in 4 months. Had serpentine belt and would take out the fornt bearing. everything else was fine, it would just start whining. Of course it had lifetime replacement on alt. but I was getting tired of replacing. I went to the local industrial bearing shop and bought a good set of timkin bearings. That rebuild lasted another 150K miles. truck had 343K on it when we traded it off.

I also rebuilt a couple of large 24 volt alternators on WABCO heavy equipment. That is one impressive alternator. All it needed was new bearings and brushes about 30 minute job, and it saved my employer about $400. Some times it is nice to be able to work on things.

I have an old under hood 12v to 120 volt converter from about the 50's that I thought I would wire in the 12 volt circuit. It has a switch to run high dc voltage also. I have some old drills and saws that will run on both ac and dc, I want to see if that is really true.

Thanks for posting the info.

[scrapcan]

PatMarlin,

Thanks for the link. I have been looking for a small affordable diesel engine for a long time. Just to tinker with and maybe do something useful like you have. Currently my family owns a family diner, no problem getting quality oil at the local greasy spoon! They do not use hydrogenated oils, bad for you dontcha know.

I also came up with an old miller portable welder that has an trashed onan (can't remember the model) that would be a great candidate for a diesel replacement if I could find or build mating plates to match it up.

anyone have some onan parts laying around?

Jeremy

[floodgate]

Flyboy, Buckshot:

If I can rely on my increasingly shaky memory, the Martin B-26 (nicknamed "The Flying Floozie, due to its small wing area - "no visible means of support") saw most of its action in S. E. Asia in WWII, though I seem to recall they were used in the high-speed strikes on the Romanian oilfields, too. A friend (now long gone) flew in them in the '40's.

The Douglas pictured above was originally designated the A-26 "Invader" as an attack aircraft, but was later (aftert the War) reclassified as a bomber - "the second" B-26. Back when I was involved in weather reconaissance, cloud seeding and fog suppression in the 1960's, one of our contractors was Wally McDonald, whose main business was buying and selling surplus aircraft to "friendly foreign powers"; he was also the stunt pilot who finshed the flying sequences in "Flight of the Phoenix" after Paul Mantz was killed. He had a Douglas B-26 modified for spray work - the first time he tried it with a half-full load, he discovered the supplier had failed to put baffles in the tank - it took some gentle handling, and a lot of quick work on the trim controls - but he did get it back on the ground safely. He had previously done the early tests on modifying a De Havilland (?) for firefighting, by skimming over a lake, dropping a scoop, and taking on a couple of thousand gallons in 30 seconds or so, so he WAS qualified for such work.

I could go on about "pilots and planes I have known", but won't - for now. Please feel free to correct any errors or mis-statements I may have made.

floodgate

[PatMarlin]

PatMarlin,

Thanks for the link. I have been looking for a small affordable diesel engine for a long time. Just to tinker with and maybe do something useful like you have. Currently my family owns a family diner, no problem getting quality oil at the local greasy spoon! They do not use hydrogenated oils, bad for you dontcha know.

I also came up with an old miller portable welder that has an trashed onan (can't remember the model) that would be a great candidate for a diesel replacement if I could find or build mating plates to match it up.

anyone have some onan parts laying around?

Jeremy

Onan's are now boat anchors. Can't get parts anymore, as they quit selling and did not comply with the new EPA requirements. Best to do an engine swap.

There should be a Kolhler engine that will bolt up to the Miller, as that's what they use now. Call Miller, and Kohler.

[scrapcan]

PatMarlin,

The point is that we as a society need to be of a mindset that we can fix things, not just replace. Pretty much the whole jest of this post is we can still build things.

There should be a bunch of onan parts out there from dead units, not all will die from the same thing. The current mind set is to crush or shred and send overseas to have it come back as a replacement. Lost industry, lost jobs, and redistribution of wealth doesn't sound good. But given the circumstances it is the direction we all are having to drive.

Thanks for the info and I will start looking a the bolt pattern for mating to a kohler. They are alot better engine anyway, and not just because they are still available.

Jeremy

[Texasflyboy]

What size pulley did you use on the B&S?

Here is the complete parts list:

1. Alternator - AC/DELCO 12SI Internally regulated alternator. You can read about 10SI and 12SI AC Delco alternators here (http://www.madelectrical.com/electricaltech/delcoremy.shtml)

2. Briggs & Stratton 3HP Sideshaft engine. Any sideshaft engine will work, what is highly desirable is to have a 1/2" or 5/8" keyed shaft, which my weird little model (Model 80232) did NOT have. It has a 9/16" keyed shaft. So I had to buy a 1/2" pulley (sheave) and bore it out to 9/16".

3. Pulley - 5" O.D. Smooth bore (no keyway) Got if from Graingers here (http://www.grainger.com/Grainger/wwg/itemDetailsRender.shtml?ItemId=1611767814). Just get a pulley that will work with your shaft for YOUR engine. Again, having a keyed pulley is very desirable. I spun my no keyway pulley the first time I placed a 95% load on the alternator.

4. Common everyday variety 12Volt car battery. I got mine from Autozone, has top posts (you can use side posts) and it has 550 Cold Cranking amps.

And as I stated, the bracket, wiring, switches, and other parts I had leftover from other projects.

Feel free to email me for advice or help if you need it.

I've since added a dedicated 12 Volt Power outlet (all weather), fan belt guard (very important), and a Briggs & Stratton Maintenance Minder (Hobbs Hour timer for B&S Engines) you can see a picture of one here (http://www.manddsmallengine.com/briggs/tools/5081d.html). I got mine on fleabay and paid $14.00.

[PatMarlin]

If you want some more power out of the delco, I'd go larger in HP. With a 6hp diesel, that 65 amp alt could still easily take more power, and put out more amps.. :drinks: