Generator Not Cranking - Onan Microlite 4000

[brisath]

When I push start switch on the unit, I hear the fuel pump and a click from the solenoid but no action from the generator. Here is what I've tried so far:

-Tested batteries, showing 12.8+ and I've got 3 deep cycles.
-Ran the engine and tried starting with engine running.
-Half a tank of gas.
-Found that the 30 amp breaker switch was off. Turned it on but still doing same thing.
-The last couple times out, it was having a hard time starting, and I usually had to run the engine to get it started.

[brisath]

Thanks DaHose but I have confirmed it does have a starter as Texas indicates. It is just in the back out of reach. I'm going to double check connections first though and make sure everything is clean and grounded properly then I'll work on dropping it.

[TEXAS]

Jose What you have is called an exciter cranked generator.Two sections. DC section for starting. AC section for the voltage output. The Microlite has a starter just like a car does.

[DaHose]

Look around on yours and be absolutely sure it has a separate starter motor. Mine does not. I have an Onan 4000 and I discovered that it has a crazy start solenoid setup.

The crazy solenoid uses the generator as the starter motor, then when it's spinning I release the start button. That converts it back into a generator. At first I pushed the button to start the genny and heard the fuel pump running, but there was no cranking. I tested all the electrical and narrowed it down the starter solenoid. I found a NOS part for $25 dollars and the genny started on the second try.

Jose

[fischer]

One more thing to check is a good ground. You need battery and ground for everything to work properly.

[TEXAS]

You will have to drop it. To get the top off. That is why I no longer work on them.

[brisath]

The coach is a 1995 and there are 289 hours on the generator. It appears I am going to have to drop the generator down out of the RV to get to the starter.

[MEXICOWANDERER]

How many hours are on the machine? What year is your coach? Your carbon brushes could be hung up in a kludge of carbon inside the brush holders.

Remove starter and put on bench

Scrape a distinct line on the starter body and over onto the end cap. You need to replace the cap exactly like it came off.

Remove the two l-o-n-g bolts holding the cap to the starter body. Removing the cap may mean prying it off with a couple of screwdrivers.

Look inside. Can you see the brushes (or what's left of them)? Use a pair of needle nose pliers. CAREFULLY lift each brush against the brush spring. Are the brushes sticky? Clean out using brake clean so you can see better.

Are the brushes worn down so far that their braided copper wire leads very near to the steel brush holder frame? That means the brushes are worn way down. If you seemingly un-stuck the brushes with movement and brake clean, reassemble the starter and test the motor in your bench with a set of jumper cables. The motor will jump with torque so if you have a vise, use it, if you have a vice, use that too. No joy with the jumper cables? Time for the yeller pages.

[KJINTF]

Just a thought
Try to get the starter motor to move a bit the brushes might be not making a good contact - My Honda lawn tractor does that every now and then turn the motor a bit and all is good for another season

[brisath]

I like the simple solution idea KJINTF. More like this are welcome.

If your referring to moving the flywheel, I've tried that a few times and it is spinning freely and doesn't seem to change anything regarding cranking.

[KJINTF]

Try a simple fix first
Get a long flat blade screw driver and crank over the engine a few degrees
Seen the starter motor get "frozen up" and this cured the issues for many years

[brisath]

Volts seem to be fine coming in and when I hit the start switch the cable going out of the solenoid registers similar voltage. My meter is jumping around quite a bit but it seems to be close to 13 on both sides.

So now I should look at starter replacement?

[TEXAS]

Take the door off. On the left side you will see a big black solenoid with two large terminals on it. One will have battery power all the time. That side is where the battery hooks up. It may have BATT printed on it. The other side supplies power to the starter. It should have power when you try to start it. If it does not you have a bad solenoid. If it does have power the starter is bad.

If you need a service manual. Go to smokstak Onan section post a full model and serial number. With an email address. You will receive a manual for free.

[brisath]

There is no cranking at all currently. The last time it didn't start when I was out camping, I remember a couple slow cranks and then it went to the state it is currently in, where no cranking is happening.

Texas, can you give instructions on a simple test to determine if power is getting through to the starter? I assume it's fairly easy with a volt meter but electrical testing doesn't come easy for me.

[TEXAS]

Are you sure power is getting through the start solenoid to the starter.