Generator Disassembly

[D45]

How does the electrical generator motor come off of the gas powered engine?

I have a Craftsman 5600w with a 10hp Briggs......given to me

Generator motor is burned up. Briggs motor works great

I want to separate and remove the generator motor

 

[PoorUB]

There is a through bolt on the end of the generator shaft that runs into the crankshaft of the generator. The engine shaft is tapered. In your case, beings the generator does not work you can beat on the generator rotor and the shock should brake the taper lose.

Now the bad part. The engine shaft is tapered. Like this,



There is not much you can do with it unless you swap out the crankshaft, or remove it and have someone machine the end of the crankshaft straight.

I see there is someone on eBay selling adapters that slip over the shaft. No idea if they work or not, for instance, (No idea if this will fit your engine!!) https://www.ebay.com/itm/132083677591

 

[theoldwizard1]

Go to James Condon's YouTube channel. He shows a couple of different methods in various videos.

 

[nadogail]

You may find yourself asking ,"why would anyone build it this way"?

The answer is, "That was the cheapest and fastest way to get the job done".

 

[jubilee]

I hang generator with the engine facing down. Rig safety chain or wire with slack so engine won’t hit floor when the two come apart.
Spray as much of shaft with 50/50 atf/acetone as possible.
Rap end of shaft with brass hammer ( or such) every now and then during day.
Usually second or third morning, when I come out to shop, they’re hanging separated.

 

[stonesfan68]

Go to James Condon's YouTube channel. He shows a couple of different methods in various videos.

James Condon

 

[redmondjp]

Yes James Condon does show a few different methods, but to save the viewer several hours' worth of hunting, I'll give the cliff notes version of my favorite method:

Remove bolt holding generator rotor onto the motor crankshaft. Fill hole with liquid - James has used water, I would use ATF or any type of motor oil. Then thread in the bolt and use an impact gun to tighten it until the hydraulic pressure pops the rotor off of the crankshaft.

Ingenious if you ask me.

But I concur with the above poster with regards to the tapered crankshaft, which about 97.6% of all of those type generators have. You really can't do much with them unless you are a machinist or disassemble the engine and install a different crankshaft.

 

[theoldwizard1]

Remove bolt holding generator rotor onto the motor crankshaft. Fill hole with liquid - James has used water, I would use ATF or any type of motor oil. Then thread in the bolt and use an impact gun to tighten it until the hydraulic pressure pops the rotor off of the crankshaft.

The bolt has to seal, so several wraps of plumber's Teflon tape are required.

 

[D45]

They sell a tapered to straight shaft adapter for around $40

 

[PoorUB]

If the end of the generator rotor is threaded I have also cut a round shaft that just fit through the rotor, and run a bolt against it to pop them lose.
I had a small engine shop for a few years and did many engine rebuilds or replacements on generators.

 

[kelpaso1]

If the end of the generator rotor is threaded I have also cut a round shaft that just fit through the rotor, and run a bolt against it to pop them lose.
I had a small engine shop for a few years and did many engine rebuilds or replacements on generators.

Same trick is used to remove the clutch from an ATV crank.

 

[Showkey]

You may find yourself asking ,"why would anyone build it this way"?

The answer is, "That was the cheapest and fastest way to get the job done".

There are several engineering reasons for the taper:

1. Clearance is zero between the rotor and crank, so rotor clearance to the stator can be controlled. A slip fit with set screws would be too sloppy. Taper can be almost zero runout.
2. Taper allows the rotor and crank to be a perfect alignment. precision ……..Same reason they use a taper chuck on drill press and lathe center.
3. Taper allows the crank and rotor assembly to be supported by three bearings.
4. Compact package compared to belts or drive coupling.

The taper fit is actually more costly to manufacture.

 

[Metallitubby]

Remove bolt holding generator rotor onto the motor crankshaft. Fill hole with liquid - James has used water, I would use ATF or any type of motor oil. Then thread in the bolt and use an impact gun to tighten it until the hydraulic pressure pops the rotor off of the crankshaft.

Ingenious if you ask me.

This method is standard for one specific Honda generator. When I explained the procedure to technicians, they'd give me the "no waaaaaay" response. It's nothing new, but it definitely works.

 

[D45]

I wonder if the stator can be rewound , where it would be cost effective?

It's a nice generator but the stator smells like its burned

 

[PoorUB]

You should be able to buy a replacement stator unless it is an antique.

Plug in your model number here and see what comes up.

https://www.searspartsdirect.com/combo/0247-1234638/craftsman-generator-parts

 

[D45]

Craftsman 580.325610

5600w / 8000w with a 10hp Briggs

Generator stator​

Part #191042AGS

The manufacturer no longer makes this part, and there's no substitute part

 

[PoorUB]

Probably why you got it!

Have at it, knock it apart and toss the generator head and use the engine for something else.

 

[D45]

I tapped the end for a bolt and added a solid steel bar inside

Ran the bolt down and it won't pop off

 

[D45]

I'm going to pull the spark plugs and insert some rope, to keep the crank from rotating

 

[nadogail]

I'm going to pull the spark plugs and insert some rope, to keep the crank from rotating

Good Luck; and please let us know how your plan worked.

 

[Noltz]

This method is standard for one specific Honda generator. When I explained the procedure to technicians, they'd give me the "no waaaaaay" response. It's nothing new, but it definitely works.

That's surprising. In school we're taught a similar method as a automotive tech to get pilot bearings out of crankshafts. Pack them with grease, find a bolt the same size as your pilot nose and use it as a punch. Drive it in and the grease transfers the impact force to the back of the bearing - which pops them out.

 

[PoorUB]

I tapped the end for a bolt and added a solid steel bar inside

Ran the bolt down and it won't pop off

Take a BFH and beat on the rotor. It is junk already, you won't hurt anything else. Put a wood block under it to support it.
It is crude, but effective.

 

[D45]

I'll try smacking it with a hammer tomorrow

 

[theoldwizard1]

I wonder if the stator can be rewound , where it would be cost effective?

In Pakistan it is !

 

[theoldwizard1]

I tapped the end for a bolt and added a solid steel bar inside

Ran the bolt down and it won't pop off

Need a bigger wrench !

 

[Metallitubby]

That's surprising.

You've got to remember that our Power Equipment dealers vary wildly from great to guys in a chicken house. The training isn't exactly what I'd call "stellar" for the vast majority of most current power equipment servicing dealer (currently).

 

[D45]

It's removed

Looks like the shaft is 7/8" diameter

Wonder if I can cut the length down before the area were it starts to taper, and have room for a clutch

 

[nadogail]

How much shaft length will your Clutch need? The clutch maker can tell you.

 

[PoorUB]

Can yuu buy a clutch for a 7/8" shaft?

I belive you will end up with a 1" clutch ad sleeve the shaft.

No shaft adapter available?

 

[D45]

I might just grind the shaft down to 3/4"

I just don't want to toss the engine, it starts and runs great

 

[D45]

Predator 301cc (8HP) shaft specs:
Diameter: 1.00" - 25.4 MM
Length: 3.48" - 88.50 MM

Predator 420cc (13HP) shaft specs:
Diameter: 1.00" - 25.4 MM
Length: 3.48" - 88.50 MM

So, both the 301cc and 4200cc engines have the same shaft specs

The Predator 6.5 HP (212cc) has a 3/4" diameter and 2.43" (61.70 MM)

I will look around and see if I can find a 7/8" tapered to straight adapter for somewhat cheap, even if that means the end product will be a 1" straight with keyway

 

[PoorUB]

Keep in mind with w 10HP engine you will want a 1" clutch. A 3/4" clutch will not be rated for the horse power and not hold up.

 

[PoorUB]

I might just grind the shaft down to 3/4"

I just don't want to toss the engine, it starts and runs great

Keep in mind to get a key way cut and turn the shaft down you will need to remove the crankshaft from the engine.

 

[PoorUB]

Just buy one of these and be done with it! I would check with the seller and makes sure it fits first.

https://www.ebay.com/itm/132083677591?hash=item1ec0ccf997:g:DYAAAOSwqxdTqvNo

 

[D45]

Wow almost $70 for the adapter on eBay

I think I found it for $37

Generator high Pressure Washer Engine Bushing crankshaft Adapter Taper to 1" inch https://www.amazon.com/dp/B097G63PP7/?tag=atomicindus08-20

 

[PoorUB]

At least with Amazon returns are simple if it doesn't fit.
eBay is a bit questionable in that regards.

 

[nadogail]

More than once I have tripped myself up by trying to "get by" with an under rated part because it was a few pennies cheaper. If you might need to return something you discover doesn't fit; better clarify that before spending your money.