Filament not extruding; no clog and motor turning?

I have a self built Allunar M505 printer (from a kit), and with a bit of work the printer has been doing fine until the filament suddenly stopped extruding. I use PLA and a direct extruder (not a bowden). I've attached a picture of the open extruder body. The hobbled knob turns and seems to be in contact with the filament, but the filament won't move. I used a sharpie to mark a spot on the filament so I can tell if it's moving. When I pull the filament out, there are no teeth marks on it. I need to print some gears for a project I'll be working on shortly, so I want to get the printer fixed sooner than later. If I missed any important information, please ask! Thanks for the help in advance!

Also, this is my first post, so go easy on me guys

With name like apple pi? you want us to go easy on you.... (insert evil laugh here)

When you pull out the filament you should see teeth marks.

From the photo it looks like your filament sitting above the gear on the smooth part of the extruder gear.

Remove the filament and look down the hole where the filament goes, check you can see the teeth in the path. I suspect you wont or it very off centre
If you lucky you can adjust the location of the the gear on the stepper motor shaft somehow,

Dust seems correct. I have had my toothed gear slide on the shaft when the set screw came loose. I'll bet that is what has happened and your gear is now below the filament. Let us know what you find out.

your spring looks like it is fully extended thus not putting pressure on the lever, i think it is missing a bolt that should be inserted inside the spring so that the existing bolt screws down onto it to adjust the tension.

somthing like in this extruder

Agree with the above... increase tension on your spring so that there *are* teethmarks on the filament. Your extruder motor should skip steps before the drive gear starts slipping.

levers 101 people, when that inside spring is fully extended, the idler is at its closest position to the geared pulley.

Quote
Dust
levers 101 people, when that inside spring is fully extended, the idler is at its closest position to the geared pulley.

agreed but it looks like there is NO tension on the spring because the tension bolt is just sitting inside the spring atm.

Thanks for the suggestions guys! I ended up adjusting a nut on the screw so the spring was more tense, and it works fine now. The screw has never been like that so I don't know how it was working before lol. This looks like a great forum and I'll definitely come back here if I have any trouble!