Generator seized

[woody367]

Have a generator that seize. oil fill plug blew off and oil shot every where. It should have shut down as it has a low oil shut off bet it did not. Soaked it a few days with PB Blater, changed the oil,pored oil down the sparl plug hole and oiled the OHV. Got it free but it has only 60psi of compression and 80psi with wet test. It is a ALL-Power apgg7500 not the best gen but work well and only 50 hours on it. It was given to m,e as a freebie so would like to maybe rebuild it as a project. I have never split a gen head from a engine and not sure what I am in for.Anyone have any suggestion beside junk it or boat anchor ? Thanks

 

[nadogail]

It depends on the shaft of the alternator and if it has an outboard bearing.

If so I would buy a 13 horse Chonda (Chinese made Honda Clone) and a Lovejoy coupling and call it a GenSet.

 

[58Yeoman]

Thanks for sharing.

 

[BillK]

Woody,
Dont waste your time trying to rebuild it. When all is said and done it will probably cost you more than a replacement engine. You can take it apart and look but if it got to the point that it seized up the piston and cylinder are probably junk and most likely the rod and crank too. Most of those engines use an aluminum connecting rod with no bearing so when it runs out of oil the rod gets chewed up along with the crank. If it has low compression the piston is probably half melted too

 

[Shade guy]

I would fix it. You can get a rod off ebay for under 20 bucks. Clean the crankshaft with muriatic acid and a fine emery cloth To get the rotor off the generator you will need a bolt with the same size as the one that holds the rotor on. There will be threads in the end off the rotor that you can force the rotor off.

 

[woody367]

Think I will pull it apart and see how much damage there is and go from there. I will look for a vidieo on how to remove the gen head. I guess I can't do asnymore damage as it is worthless now. Maybe I will learn something along the way.

 

[Shade guy]

heres one

 

[woody367]

How can I tell if this engine has compression rel

 

[Lassen Forge]

(1) Take out the spark plug
(2) Put thumb over spark plug hole
(3) Pull the engine through.

You'll feel the compression.

If you need more, then get a compression gauge.

 

[theoldwizard1]

Almost all portable generators attach the rotor/armature to the engine via a tapered shaft.

Multiple videos on YouTube on how to remove it.

How To Remove a Generator Armature

 

[woody367]

Was told that 60psi of compression would be good if the enginehas a compression releif valve. How do I know if this engine has a releif valve?

 

[Shade guy]

All the engines I have worked have a relief valve on the camshaft sprocket. When you tear it down you will see it.

 

[woody367]

I was hoping to get a true compression test on it but with a releif valve I can not do that right?

 

[theoldwizard1]

Was told that 60psi of compression would be good if the enginehas a compression releif valve. How do I know if this engine has a releif valve?

Most hand start engines over 5 hp have some type of compression release.

 

[Shade guy]

I wold not worry about compression so much. Do a leakdown test
I stole this from a now defunct forum


Building a simple Leakdown tester

This tester is a valuable tool that allows you to put some air into the cylinder area and see where it leaks out. As you can see from the picture the tester consist of a pressure regulator, hose with spark plug thread and some fitting to connect to your air source. Engine Leakdown TesterThe regulator I used here is a Sears 282-16025 and is still available for $22.99 at Sears. The hose and fittings are available at auto parts stores or in compression tester kits. Once you have made your leakdown tester, you will need to have the piston at TDC on the compression stroke and lock the flywheel so the engine cannot turn. Screw the tester into the spark plug hole and slowly dial about 30 to 40 pounds of air while listening where it comes out. More air than this can be dangerous and is not necessary. Be sure to isolate the breather hose from the carburetor, so you are not mistaken where the air is coming from. Here's some areas to look, listen and feel:

Muffler - leaky exhaust valve
Carburetor air horn - leaky intake valve
Breather hose - worn or damaged cylinder/rings
Head area - leaky head gasket or warped head

This simple tester will help you pin point areas not sealing tightly in your engine. I have had great success with this, having built my first one about 25 years ago before leakdown testing became popular. Some people also use it to hold the valves in place while installing retainers on OHV engines.

 

[Bretny]

It depends on the shaft of the alternator and if it has an outboard bearing.

If so I would buy a 13 horse Chonda (Chinese made Honda Clone) and a Lovejoy coupling and call it a GenSet.

Many generators have a tapered shaft on the engine because they use the engine bearings to hold that side of the gen head.

You will need to find out what's wrong with the engine first or look for a new engine. But since it was chinese and free I would throw it up for sale and call it a wash.

 

[firebirdparts]

All the engines I have worked have a relief valve on the camshaft sprocket. When you tear it down you will see it.

This right here. If you don't see anything external, look for a camshaft with moving parts hanging on it. That's the only indication I know of.

 

[Robbie B]

Think I will pull it apart and see how much damage there is and go from there. I will look for a vidieo on how to remove the gen head. I guess I can't do asnymore damage as it is worthless now. Maybe I will learn something along the way.

Can’t eff it any worse.[emoji2371] [emoji1787] Have fun.