SonexBuilders.net

Just the mounted Aerovee in the Sonex and the starter will not come out enough to engage the flywheel. It seemed to work once then wouldn't do it again , just makes a grinding noise.
Is it even possible to put the flywheel on backwards?

Any ideas whats going on?
John

I doubt it's possible to mount the flywheel backwards. Does the engine turn freely?

Some starters are designed so the bendix (little gear) will stay engaged to the flywheel until the engine starts. But you say the starter is making a grinding noise?

You may want to start by taking the starter off and taking it to the local auto parts store so they can bench test it.

The grinding noise is when the wheel spins out and tries to engage but does not come out far enough so it is grinding on the flywheel teeth. Seems the starter is working but is not engaging. John

I am thinking maybe the battery is low. Going to check that out. John

John
A battery in a low state of charge will cause the starter to make a lot of noise. As the solenoid draws power, pulls the bendix out to engage the flywheel there is a loud click or knock as the starter teeth contact the flywheel. If the battery is low then the solenoid does not have enough power to pull the teeth into complete engagement and the bendix (starter gear) is withdrawn. As long as the key or button is held then this
is repeated by the starter causing a rapid and loud clicking to occur. This might be what your hearing since you said the starter has worked before. Check the state of charge and you might find your problem there.
You can send a PM if you would like for any help if needed.
Frank
ONEX 090
At home now installing hydraulic brakes (SONEX)
Prepping for paint
Making cockpit minor changes
etc, etc, etc....

I have 12.4 volts. I'm thinking this should be enough. John

Has it worked in the past with no problems or is just now going into service. 12.4 volts is plenty. Sometimes starters needs shims to line up with the flywheel teeth. If it's chattering against the flywheel, then the throw out bearing is probably ok. Check for looseness.

Yes the starter does chatter against the flywheel. Everything is tight.Did not have shims when I took it off. From looking at it,looks like it is to close to the flywheel gear about 1/16 or 1/8 " . I'm thinking of taking engine off again to see what's going on. John

Don't pull the engine yet...... Especially if you can rotate engine freely by hand. You said it worked once normally, yes? I'd start by charging battery overnight and give it another shot. Since we don't know the history of the acft, engine or battery, that's where i'd recommend starting (forgive the pun). 12.4 resting voltage doesn't necessarily tell the whole story about battery condition .. Good luck.

Make sure you have a good heavy ground going from the starter back to the battery. Don't rely on the ground going through the accessory plate. The red anodize on the outside can make it non conductive. I think.there was a service bulletin out on it at one point. The same goes for the mags. Run a seperated ground wire to them.

Keith
#554