[jswillems]

Over the past year or so I have become very interested in film photography and collecting film cameras. As I've always enjoyed working with my hands, I wanted to learn more about repairing and restoring film cameras. Not wanting to disassemble one of my working SLRs I picked up an h1a with a jammed film advance lever for cheap to tinker with. Unfortunately I think I may have bitten off more than I can chew . From what I've read the most common issue seems to be with a misplaced lever (I believe it is the one circled below) which appears to be in the correct position.



The main problem seems to be with this gear which is very stiff and does not want to rotate (though I'm not certain it is supposed to).



The shutter button moves freely up and down as does the mirror, so the jammed lever appears to be the only problem. Any tips or advice that anyone has would be greatly appreciated as I;d love to get this camera working again since cosmetically it is in great shape. Thanks!

[MysteryOnion]

What part have you tinkered with so far?

[jswillems]

I haven't done a lot of tinkering yet for fear of damaging something. I pulled the bottom cover off and examined the mechanics and as I said, everything seems to be working as it should except for that one gear which seems jammed. There seems to be some sort of odd discoloration around that gear as well. I thought about maybe trying a drop or two of some penetrating oil but I'm not sure that's a good idea as I don;t want to oil getting somewhere it's not supposed to go.

[MysteryOnion]

Don't oil it yet.
The jam could be part of the mirror not resetting itself.
Did you try to throw the camera into rewind?
Do so and and with your thumb, push the sprocket roller slowly in the direction of rewinding.
If it works, then try to advance the camera slowly. If it does not work, then the problem is deeper.
Also, are the shutter curtains open or seemingly half transported.

[jswillems]

Thanks for taking the time to help! Pushing in the rewind button and moving the sprocket roller didn't do anything. The shutter curtains look to be half transported.

[MysteryOnion]

Quick look at the S1a

When cocked and ready to shoot






After and fully released






This is a quick look with the mount removed... sorry not the best image right now.

[Blue]

It likely needs a cla (cleaning, lubed, adjusted) which is a basic service, but is out of my skill set.

[MysteryOnion]

The shutter curtains look to be half transported.

Are the curtains slacked or still with tension?



Note that the pin (Green Arrow) in my example is not contacting the bar yet (Red Arrow). Is the bar in good shape that is slides easily (Yellow Arrow)?

[jswillems]

The first curtains seems to be still wrapped around the pinion shaft and the second is tensed. Yes, the bar is in good shape and slides easy. It's starting to seem like this repair won't be as simple as I was hoping and since the camera appears to be in good shape otherwise, I'll probably end up sending it to Eric for a CLA so I don't end up ruining it.

[Peter Bermes]

Hi, I accidentally stumbled accross your thread concerning the jammed gearwheel in your pentax. (As you posted this question about a year or so ago I do hope you didn't throw your camera away or that someone else had solved your problem meanwhile) Anyway its an easy cure: You've circled exactly the center of troubles! Its not the gearwheel itself though but the black lever that sits in its recessed niche and which is protruding up from inside the camera! If you just move this black lever all the way towards the camara back and support this by joggling the other lever that sticks up through the slot on the other gearwheel on your 2nd foto at the same time, you will immediately feel your blockade will be gone! (provided of course that everything else like shutter curtains and all is ok!) I had this same thing on my S1a yesterday and it took me 4 hours to get to this point.... Hope I could 've still been of assistance.

Regards Peter