[aezarien]

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That's why I didn't even bother with it. There were too many mixed results. I figured if I was going to open it up and tinker, I may as well go for it. I followed the directions posted in this forum to replace the entire assembly from the pop-up flash of my istDS. I have used it almost daily since I replaced it about a month ago and no problems yet. Here is to hoping that does the trick. It cost me $0, the other camera still works, and the flash pops up with the defective part, too. It was tedious and took a few hours, though and definitely not something I would suggest if soldering isn't something you are comfortable with or you don't have a steady hand. It isn't incredibly difficult, but you do have to be mindful about what you are doing. The printout of all sides of the camera with two-way tape to hold the screws was very helpful.

[photogem]

Apologies photogem, you're right - I've removed the original message since the info was incorrect (much to my disappointment since I've still got bust K50! Ahhh!)

Most likely very easy to repair if you open it again, my guess is that you forgot to connect the mechanism for the aperture to the horseshoe correctly.

If not, then you have seriously damaged something (possibly due to the very same hurry you were in when writing your first post)
Did you check with a lens and battery in the still open K30 if all works as shown in this video (near the end 14:30 onwards):

You Tube

You Tube

???

Whenever I repaired a K30 or K50 I did that. One might have produce a bad or cold soldering joint (which leaves the solenoid out of function).
So one first checks and if all is alright one reassembles it!
good luck

---------- Post added 07-07-17 at 02:19 AM ----------

That's why I didn't even bother with it.

I guess you mean you didn't bother with modifying the green solenoid?!

I agree, for myself (and I am not accusing anybody else with this!) this would be a stupid and lazy option, my thoughts were exactly how
you present it:

There were too many mixed results. I figured if I was going to open it up and tinker, I may as well go for it. I followed the directions posted in this forum to replace the entire assembly from the pop-up flash of my istDS. I have used it almost daily since I replaced it about a month ago and no problems yet. Here is to hoping that does the trick. It cost me $0, the other camera still works, and the flash pops up with the defective part, too. It was tedious and took a few hours, though and definitely not something I would suggest if soldering isn't something you are comfortable with or you don't have a steady hand. It isn't incredibly difficult, but you do have to be mindful about what you are doing. The printout of all sides of the camera with two-way tape to hold the screws was very helpful.

First time I did it it took me also 2 hours.
But as I now have all the photos of the sides of the camera to "store all those screws at the right place" it took me 1 hour with the next K50 and
30min for 2 x K30's which I did next.

All work very very well.

[jjnevis]

Have decided to order spare part and replace. Everything was put back together correctly, but the "fix" I made to the existing part was incorrect and has rendered it useless for it's intended purpose.

[kingbird72]

Further to my previous post, it's sad that Pentax didn't even bother to get back to me on the aperture block motor issue with my K50. I've decided to not repair the unit and instead I'm going to get the K3ii instead when it goes on sale here in Canada sometime, hopefully soon!!!

[photogem]

Have decided to order spare part and replace. Everything was put back together correctly, but the "fix" I made to the existing part was incorrect and has rendered it useless for it's intended purpose.

Hope you ordered the right part, i.e. the white solenoid and not the same one which might get faulty again.

---------- Post added 07-09-17 at 01:53 AM ----------

Further to my previous post, it's sad that Pentax didn't even bother to get back to me on the aperture block motor issue with my K50. I've decided to not repair the unit and instead I'm going to get the K3ii instead when it goes on sale here in Canada sometime, hopefully soon!!!

K3 or K3II are great cameras, another step, no daubt.

Nevertheless, it might be worth taking this step to repair it oneself.

I think Ricoh will only get back to you if you send it in and then quote you repair costs (around $ 130) but you will have the same green solenoid inside again which turned out to be the main problem. We have a few cases where it got fault again.
I would only use the white solenoid.

[jjnevis]

@photogem - do you happen to know where I can order the correct spare part from? I'm in UK, but most suppliers will ship worldwide I think. I've found this one:
Aliexpress.com : Buy Original For Pentax K30 K50 Genuine Aperture Solenoid Plunger Part Camera Replacement Repair Part from Reliable part suppliers on MH DIGITAL Store

But that appears to be the green one.

I've also found this one, which looks more like it:
Pentax K-30 K-50 Genuine Aperture Solenoid Plunger Part - Made in Japan - | eBay

(Seems a bit pricey, but I guess if it fixes the problem it will be worth it in the end)
Any advice?

[athlonus]

@photogem - do you happen to know where I can order the correct spare part from? I'm in UK, but most suppliers will ship worldwide I think. I've found this one:
Aliexpress.com : Buy Original For Pentax K30 K50 Genuine Aperture Solenoid Plunger Part Camera Replacement Repair Part from Reliable part suppliers on MH DIGITAL Store

But that appears to be the green one.

I've also found this one, which looks more like it:
Pentax K-30 K-50 Genuine Aperture Solenoid Plunger Part - Made in Japan - | eBay

(Seems a bit pricey, but I guess if it fixes the problem it will be worth it in the end)
Any advice?

Yes, that is the part actually works, bought several and no problems at all. Original Japanese part.

[Hutchoman]

Just an update on my K-50. 17 day trip to China and just over 3000 clicks. No problem at all. Camera worked absolutely fine. This was with a replacement green solenoid. Yes, I know. Why replace a green with a green? Was a white solenoid shown on the original Aliexpress site when I ordered the part. A green solenoid arrived in the mail. For 15 bucks US, I kept it and replaced the dodgy green one. Served it's purpose getting me through my China trip.

[photogem]

Just an update on my K-50. 17 day trip to China and just over 3000 clicks. No problem at all. Camera worked absolutely fine. This was with a replacement green solenoid. Yes, I know. Why replace a green with a green? Was a white solenoid shown on the original Aliexpress site when I ordered the part. A green solenoid arrived in the mail. For 15 bucks US, I kept it and replaced the dodgy green one. Served it's purpose getting me through my China trip.

Yes, they cheated, now they show the green one.
Too bad because here in Germany we have the first "replacement" green solenoids failing again, just after the warranty time of 1 year.

I just see it like this: Why bother to do all this work and risk the most likely failure again if I can have it perfect with little money extra?

[TrulyAlice]

I mailed it out to be repaired by a guy in CA.

Are you satisfied with the repair? I was thinking of sending mine in to the CA guys too.

[penguinsoda]

Are you satisfied with the repair? I was thinking of sending mine in to the CA guys too.

I send mine out a few weeks ago. Turn around on the repair was pretty quick and so far so good. Although I haven't taken a lot of shots since getting it back but it seems to be working fine now.

[vladmoll]

hi
when black picture starts with my camera k 30, i open and send horse shue. Problem dissapier. Afther 6 mants, problem start again. lens is on f 22. Then i pul out magnet from mz 50 and change green chinese. 2 or 3 days work perfect. then aperture mechanism stuck, and lens now is minimun f number. when i take off lens and shoot 1 or 2 thimes without lens, i dont have mirror issue. Put on camera again lens and everithing is normal. afther 10 or 50 shoot problem starts again. aperture stock and lock minimal f number.
is it common problem with pentax camera? maybe magnet solenoid is bad and dont work all the time.

what i shood to do?

[TV95]

hi
when black picture starts with my camera k 30, i open and send horse shue. Problem dissapier. Afther 6 mants, problem start again. lens is on f 22. Then i pul out magnet from mz 50 and change green chinese. 2 or 3 days work perfect. then aperture mechanism stuck, and lens now is minimun f number. when i take off lens and shoot 1 or 2 thimes without lens, i dont have mirror issue. Put on camera again lens and everithing is normal. afther 10 or 50 shoot problem starts again. aperture stock and lock minimal f number.
is it common problem with pentax camera? maybe magnet solenoid is bad and dont work all the time.

what i shood to do?

Did you also replace the solenoid from the mz50? Or only the magnet? Because it is known that only changing the magnet does not work, you should replace the magnet and the solenoid.

[vladmoll]

Did you also replace the solenoid from the mz50? Or only the magnet? Because it is known that only changing the magnet does not work, you should replace the magnet and the solenoid.

I change all solenoid who is white.
I faund that camera work good with lense f 35-70, litlle worst with fa 28-105, but with sigma 17-70 too bad. I cant figure..

[photogem]

hi
when black picture started with my K 30, I opened and sanded the horse shoe. The problem dissappeared. After 6 months, the problem started again. Lens is on f 22. Then i pulled out the solenoid from mz 50 and change against green chinese. 2 or 3 days this worked perfect. then aperture mechanism stuck, and lens now is minimum f number. when i take off lens and shoot 1 or 2 thimes without lens, i don't have the aperture issue. Put on camera again lens and everything is normal. But after 10 or 50 shoot the problem starts again. aperture stock and lock minimal f number.
is it common problem with pentax camera? maybe magnet solenoid is bad and dont work all the time.

what i shood to do?

The magnet itself will not be the problem. I have read that one person once had a white solenoid with the magnet inserted the wrong way round, i.e. wrong polarisation, but this would not be the problem here.

I got once a K30 with a higher shuttercount for repair: The solenoid had failed but the owner had already tried continuous shooting. After a while (of course) the problem reappeared. Further damage was done and replacing the solenoid did not solve the problem.
This K30 was then for spare parts only. Replacing the complete aperture module is too expensive (about $ 250 including parts and work).

A few times it was warned, that taking the easy option of just sanding the horseshoe is not the way to go.

That this will cause further damage!

We have also heard, that contiuous shooting does sometimes release the horseshoe but will cause for sure further damage!

So this "could" be your problem.

I don't think it is a bad soldering joint, because your K30 seems to work well with the F35-70 lens:

I changed the complete solenoid which is white.
I found that camera work good with lense F 35-70, worse with FA 28-105, but with Sigma 17-70 very bad. I can't figure..

I think there is further damage, it looks like it is this small motor itself which you can see on the photo left side.

As far as I understand it and please anybody correct me here if I am wrong:
The aperture mechanism is not just the solenoid, but there is this motor included.
My guess is that this motor (or other parts?) get damaged of one tries to release the horseshoe via continuous shooting.

The Sigma lens is a large 72mm lens, i.e. inside it has much larger and thus heavier aperture blades! So more mass to be moved, more friction, the F35-70 has just 49mm, the FA28-105 just 58mm. This might explain why your camera works with the F35-70 and open i.e. no lens attached: No friction, no mass.

---------- Post added 07-27-17 at 12:29 AM ----------

Did you also replace the solenoid from the mz50? Or only the magnet? Because it is known that only changing the magnet does not work, you should replace the magnet and the solenoid.

This can be misleading:

The solenoid itself is an electro-magnet with an inserted quite strong tiny permanent magnet (top of the solenoid), I marked it red on the attached photo.

The horseshoe at the bottom of the solenoid itself is not a magnet but made out of magnetic material!

When the shuttermechanism comes into action, for a short moment some voltage is applied to the two coils of the solenoid (which make the electro-magnet part!) This electro-magnetic power then counteracts the power of the permanent magnet and releases the horse-shoe.

What people often do due to those videos in the web is that they just sand the corners of the horseshoe to reduce friction. Not recommended!