Sliding door wheel adjustment

[DIYspanner]

I want to adjust the runner wheel height to lift the bottom of the door frame off the sill.

Does anyone know what tool is need for the adjuster?
I've inserted the likes of philips, straight blade and allen keys in the bottom hole but none seem to engage with an adjuster.

 

[crank39]

Definitely will be a pozi Philips, can be a bugger to find though, keep trying

 

[foxhole]

Try lifting door with flat screwdriver slightly to take weight off adjustment thread.

 

[robinbanks]

Put your mobile phone in video mode, light on, zoom in and see if it helps you see (don't put it too close or it won't focus))

 

[DIYspanner]

All done!
Used a long reach ph2 bit with 1/4 drive ratchet. The ph2 driver handle was too thick to get the driver blade level and seated on the adjusted head.
Now the door is running on the wheels, one of the bearings is growling a bit so either dry or worn.

Thanks All!