[quote=ChrisPlatt;4022456]The Pentax replacement part was motor with brass gear.
Unfortunately this item is no longer available from Pentax.
Some used cameras out there may have been upgraded.
Short of a full teardown there's really no way of knowing.
The brass gear can still be ordered (though not from Pentax), and usually the motor itself is fine, so these cameras can still be repaired. Do you know if Eric would do the job if the gear was supplied to him?
---------- Post added 06-12-2017 at 08:21 PM ----------
Interesting info from user violini (who has replaced a number of broken gears in MZ series cameras) - taken from
this thread on the MZ-5n:
Originally posted by violini When the bottom cover is removed, you can see the manufacturing date stamped on the metal plate. All the MZ/ZX series from 2002 have metal gear on the mirror motor shaft. Also the company changed the name to Pentax Corporation (from Asahi Opt.Co. Ltd.) in 2002. If your camera is a pre-2002 one, I would guess that whoever replaced the mirror motor didn't assemble the camera correctly. Please refer to the "mirror motor" threads " MZ5n mirror blocked, service manual?" post #62. There is a plastic arm (behind the yellow gear) extends from the gear box to the shutter block to trigger the shutter to fire. When the yellow gear is removed, you'll see two plastic levers, the one on the right is for setting the lens diaphragm, the one on the left which is extending down, is shutter charge lever. The two levers are connected by a very fine coil spring. Also mentioned in that post, the yellow and green gears are synchronized by mating the holes at the rims. The gear box cycle runs like this: when the shutter button is pressed, the mirror flips up, the aperture is set, the shutter fires, the mirror returns to 45 degree angle, the diaphragm opens up, the power is off. If it is any where in the middle of the cycle, the power is always on, which is not controlled by the external power switch. Therefore, I would suggest that you check the synchronization and the two levers behind the yellow gear.
If true, then the MZ-6, which was introduced in 2001, may well have some bodies with an OEM brass gear.
---------- Post added 06-12-2017 at 08:26 PM ----------
Originally posted by Swift1 did you see my post about the MZ-L eyepiece and being able to use standard Pentax eyepiece accessories?
Yes, I did, thanks. I was already aware of this, though.