Testing, testing 1 - 2 - 3!

[monte350c]

I am in the process of doing a couple of induction motor conversions - and I sure would like a good way to test the output.

It's important to know since you can't really make a set of blades unless you have some idea about the output (and input) the alternator will need.

So I decided to put together a power unit that could drive a variety of alternators. I don't know what it is about Briggs & Stratton motors, old ones seem to follow me home like lost puppies. I had 2 - one with a good bore, but over and eigth inch of end float on the crank, and the other with a trashed bore but good end float.

So I took the sump off the one and put it on the engine with the good bore, even got very lucky with the gasket (reused it!) After a little fiddling around with carbs and diaphragms etc. I've got a great running unit that starts easy on the first pull.

One oddity is because the good sump was off an older engine it had a low style oil fill. The motor it went on had a high style oil fill. So now there's two oil fills!

The bad sump:

The thrust suface around the crank bearing is trashed.

So next I went to Home Depot and bought a bunch of eighth inch by 1.25 inch angle. About $40 worth. This was the most expensive part of this project. It would have been better to get the steel at the scrapyard.

I marked it up and cut the pieces with an abrasive wheel in the circular saw, which works pretty well. There's a top and bottom frame 12 x 24 inch, 4 uprights, and 3 motor mount tabs.

I read a tip from TomW a while ago about collecting metal shavings. Use a bag with a magnet in it, then just turn the bag inside out, take the magnet off, and throw it out. Thanks Tom that saved a lot of cleanup time.

A friend of mine is a lot better with an arc welder than me and kindly agreed to a bit of welding:

Next a trial fit of the motor to locate some holes for the motor mount bolts:

A bit of paint and some wheels from an old lawn mower:

Just for fun I hooked up an AC Delco alternator to it. I rewired the stator star and full fielded the rotor. It gives about 95 volts AC but the motor is really working into that load.

The shape of the frame means it's easy to attach different things to it.

For the induction motors I'll be making a jackshaft with some stepped pulleys to give different speed outputs for testing. It should be possible to get from 100 to 400 rpm and with that reduction there will be enough torque out of this little motor to test the alternators I'm doing right now.

Bigger alternators will need a bigger motor - but this will probably do for now!

Project cost - about $50 including the paint.

Fun!

Ted.

[hiker]

heres my old setup--put a bigger pully on the alt so the engine would not lug down..

is your alternator turning in the correct rotaion? if not it may burn out the field brushes early from lack of cooling air..popular mechanics had an artical on how to build one--back in the 60s--found it in a stack of old mags..they recommended at least

a 5hp engine to get the most out of the alt..

[monte350c]

Hi Hiker,

Yes, the alternator is spinning the same way as it would be in the bus it came out of.

This alternator is just on there for fun - the "real" work this setup will do is in testing the induction motor conversion I am doing now.

I wanted to load the little motor with something so I could make sure it was working OK - and I had the alternator on hand.

If I was going to use it for battery charging, I would definitely put a bigger pulley on the alternator to slow it down and give the engine more mechanical advantage.

Ted.

[windstuffnow]

  Pretty slick set up Ted!  Nice job!  I did pretty much the same thing using a 5hp honda.  I bought the honda to drive a 3kw genny originally for small remote power but it was kind of heavy to lug around.  Ended up using the honda with an alternator to charge my batteries then changed some brackets around to test my wind gennys...

All I use it for now is testing...

I ran into a great deal about 5 years back at a military auction.  They were selling 6hp 4 cylinder military engines still in the crate brand new.  So I bid 175.00 each and won the bid.  At the time I had only seen 4 crates on the skid but when I went to pay for them... I didn't realize there were 100 of them... ooops.  I paid for them, yep all 100 and it took 3 trips to get them home.  All I could think of was kicking myself in the butt and wondering what the heck I was going to do with them.  I uncrated one of them and it was an absolutely cute little engine.  Cleaned up the storage oil primed it up and it fired on the first pull.  Sounded like a mini VW with headers.  After a few phone calls to teledyne I found out that the 6hp was actually calculated by the military from bore and stroke and they actually produced 22 hp.  Well, as you can suspect my spirits came up considerably.  I decided I'd build a few generators and see if I could sell them....





This one is a 12kw and I loaded this thing down with all 12+ and it wouldn't stall or vary the engine speed it even started my 7.5 hp shop compressor while running everything in the shop.  Needless to say I built generators until I was blue in the face and they sold like hotcakes.   Sure wish I could stumble on another mistake like that.  I still have one left in the crate that I saved for some odd project...

More Power!

Have fun

Windstuff Ed

[monte350c]

Hi Ed,

Those little diesels are pretty neat. And that was a heck of a deal!

Ever think about putting one in a small front wheel drive car? The rated power is not all that different than an original VW bug or Austin Mini.

That would make a interesting project and depending on the donor car chosen - hopefully something light - might be quite fuel efficient and a good grocery-getter.

Reminds me - someone tell me again - why is a SUV the right choice??

I hope to report some success with the induction motor conversion soon, then on to a blade set.

Having lots of fun!

Ted.

[windstuffnow]

  Hi Ted,

     Those are gas engines... I only dream of a deal like that with diesels... I'd be in heaven!  I thought of putting one into a small car, still have one left... who knows... ;o)

Windstuff Ed

[jimovonz]

Here is a setup with all the power you might ever need, good speed control (5 gears + a clutch even!) and costs next to nothing to put together: