[jswilson64]

Aside:

WD-40 is for sure the very wrong approach. It contains white spirit and will eventually attack any surface. Even bike-enthusiast won't use it anymore for bikechains, which says a lot.

No "bike enthusiast" ever used WD-40 on a chain. An "uninformed bike-owning dolt" might have. As far back as the 1970s and 1980s, bike shop mechanics (of which I was one) knew not to do this and we'd tell any bike owner that would listen not to do this. If you came into the shops where I worked and said you used WD-40 on your chain, we'd laugh at you and then help you choose something intended for that purpose.

[West Penn]

I think you guys are being too hard on WD-40. I wouldn't use it anywhere near a camera, but it can't hurt ferrous metals. After all, according to it's MSDS sheet, it consists of something akin to paint thinner or stoddard solvant or white spirits, something akin to kerosene, and something akin to mineral oil. As I see it, the only problem with putting it on a bicycle chain is that you'll likely drive off any lubricating oil. So, if you have a sticking chain, it likely will free up the chain, but you need to follow up with oil. In any event, the WD-40 manufacturers now make a lubricant specifically for bicycle chains.

Among it's redeeming qualities, WD-40:
Protects silver from tarnishing.
Removes road tar and grime from cars.
Loosens stubborn zippers.
Untangles jewelry chains.
Keeps ceramic/terra cotta garden pots from oxidizing.
Keeps scissors working smoothly.
Lubricates noisy door hinges on vehicles and doors in homes.
Lubricates gear shift and mower deck lever for ease of handling on riding mowers.
Rids kids rocking chairs and swings of squeaky noises.
Lubricates tracks in sticking home windows and makes them easier to open.
Spraying an umbrella stem makes it easier to open and close.
Restores and cleans roof racks on vehicles.
Lubricates and stops squeaks in electric fans.
Lubricates wheel sprockets on tricycles, wagons, and bicycles for easy handling.
Keeps rust from forming on saws and saw blades, and other tools.
Lubricates prosthetic limbs.
Keeps pigeons off the balcony (they hate the smell).
Removes all traces of duct tape.
Florida’s favorite use is: “cleans and removes love bugs from grills and bumpers.”
If you sprayed WD-40 on the distributor cap, it would displace the moisture and allow the car to start.
It removes black scuff marks from the kitchen floor! Use WD-40 for those nasty tar and scuff marks on flooring. It doesn’t seem to harm the finish and you won’t have to scrub nearly as hard to get them off. Just remember to open some windows if you have a lot of marks. Wash off after use.
Bug guts will eat away the finish on your car if not removed quickly! Use WD-40!

[mlipovac]

Uh, job done! Hardly remember when I was so scared as now disassembling my K-50. Aperture actuator solenoid stuck at shutter count of only 4600 after 3 years. Images started to be sometimes too exposed, but lately almost completely dark. Thanks to this forum and internet, I've acquired some 'donor' Pentax *istDL(not in working condition because of wrong AC adapter used) for 40$ and got also SMC DA 18-55 f3.5-5.6 AL (pretty decent lens, was on *ist, I like it because of metal mount and QuickShift feature, SMC Pentax-DA 18-55mm F3.5-5.6 AL Reviews - DA Zoom Lenses - Pentax Lens Reviews & Lens Database). Salvaged 'white' solenoid from top cover(controls flash poping) by desoldering wires. But, scary part began with opening my K-50. Very useful video on step by step opening k-50 is here:

You Tube

You Tube

Notice: Don't forget to put body cap on - beware of dust on sensor! It should be all time on except when removing and returning back the front plastic from the mount. Hard part was to unscrew the screw on solenoid, it was doted with lacquer, and angle was not right... started to grind and losing the grip. Pressure on the mount side I had to apply scared me a lot, but somehow managed to deal with it. Remover 'green' solenoid by unsoldering the wires. This was also hard task in tight space, approaching the hot iron around sensitive plastic, surfaces, wires...
Well, I'm 46 years old and my eyes are not suitable anymore for this tiny wires and stuff. But somehow, with couple of hands and my wife's another hand, managed somehow to solder tiny, tiny wires on respective positions. Reassembled the whole thing pretty fast, mounted lens, said a prayer and... Problem solved, everything works like before. I hope it will last much longer than initial one.
As a bonus and reward, for approx. 40$ (and a lot of sweating) got a pretty useful lens and I have another one solenoid as spare in dead old *istDl.

To make a final point: it's worth the all fear, sweat and effort. I've got back my k-50 after long time. I hope it will stay so for a while.

[solvin_dk]

Uh, job done! Hardly remember when I was so scared as now disassembling my K-50. Aperture actuator solenoid stuck at shutter count of only 4600 after 3 years. Images started to be sometimes too exposed, but lately almost completely dark. Thanks to this forum and internet, I've acquired some 'donor' Pentax *istDL(not in working condition because of wrong AC adapter used) for 40$ and got also SMC DA 18-55 f3.5-5.6 AL (pretty decent lens, was on *ist, I like it because of metal mount and QuickShift feature, SMC Pentax-DA 18-55mm F3.5-5.6 AL Reviews - DA Zoom Lenses - Pentax Lens Reviews & Lens Database). Salvaged 'white' solenoid from top cover(controls flash poping) by desoldering wires. But, scary part began with opening my K-50. Very useful video on step by step opening k-50 is here:How to fix Pentax K-50 (K-30) aperture - YouTube
Notice: Don't forget to put body cap on - beware of dust on sensor! It should be all time on except when removing and returning back the front plastic from the mount. Hard part was to unscrew the screw on solenoid, it was doted with lacquer, and angle was not right... started to grind and losing the grip. Pressure on the mount side I had to apply scared me a lot, but somehow managed to deal with it. Remover 'green' solenoid by unsoldering the wires. This was also hard task in tight space, approaching the hot iron around sensitive plastic, surfaces, wires...
Well, I'm 46 years old and my eyes are not suitable anymore for this tiny wires and stuff. But somehow, with couple of hands and my wife's another hand, managed somehow to solder tiny, tiny wires on respective positions. Reassembled the whole thing pretty fast, mounted lens, said a prayer and... Problem solved, everything works like before. I hope it will last much longer than initial one.
As a bonus and reward, for approx. 40$ (and a lot of sweating) got a pretty useful lens and I have another one solenoid as spare in dead old *istDl.

To make a final point: it's worth the all fear, sweat and effort. I've got back my k-50 after long time. I hope it will stay so for a while.

Hi mlipovac

Thanks a lot for telling, you have done it right, and many thanks for the video you have link to. It's the best video showing how to take the camera apart.

I'm afraid, that my k-50 also have become this problem, with only 1500 clicks, because sometime a photo is overexposed. Just like you write.

luckily I also have a old Pentax-kr or kx don't remember it. I hope it have the white solenoids in both the aperture and the automatic pop-up flash. The white one should be the best, as they are made in Japan, as I understand.

ps. I am 55 years old, and my eyes are as yours, not so sharp as I was 20 years.

Best greetings,

Torben Pedersen

Denmark

[sys3175]

Torben,

the aperture block failure typically manifests itself with photos being underexposed (too dark), especially the first shot after powering on the camera after a period of rest, and using a fully charged Li-109 battery.

Let the camera rest overnight, power on and immediately take several shots in manual mode, if the first one is very much darker, then you've got the problem.

I don't think the failure could lead to overexposed (brighter) images because this would mean the aperture staying wide open, which is not controlled by the solenoid, but by the stopping-down controller that will only kick in if the solenoid works correctly (otherwise closing down all the way leading to the problem).

[solvin_dk]

Torben,

the aperture block failure typically manifests itself with photos being underexposed (too dark), especially the first shot after powering on the camera after a period of rest, and using a fully charged Li-109 battery.

Let the camera rest overnight, power on and immediately take several shots in manual mode, if the first one is very much darker, then you've got the problem.

I don't think the failure could lead to overexposed (brighter) images because this would mean the aperture staying wide open, which is not controlled by the solenoid, but by the stopping-down controller that will only kick in if the solenoid works correctly (otherwise closing down all the way leading to the problem).

Hi sys3175

You have probably right. The white photos I have taken only usurers, when I have tried my new flash for macro shots, before I have found the right settings.
Thanks a lot for you advise

Best greetings,

Torben Pedersen

Denmark

[mlipovac]

@sys3175 => you are probably right, it doesn't make sense to connect solenoid problems with overexposed images, but I've mentioned it because that was the first deviation I've noticed on my K-50 from what all we expect to be normal. Of course, my first reaction was to check camera settings, but everything was set OK and camera tended to overexpose images (in Av, Tv, ATv modes, full manual was OK of course). It may be a different issue, but after a while I've got some heavily underexposed images. Ended with completely darkness.
So, it doesn't need to correlate, but that was the roadmap of problem development in my case.

Cheers,
Mario

[nicolpa47]

Does anyone know if the *iST DL camera has the white solenoid required to repair a K30/50 with aperture block failure and, if so, does it have one or two of the solenoids?

Thanks in advance,

Colin

[mlipovac]

Does anyone know if the *iST DL camera has the white solenoid required to repair a K30/50 with aperture block failure and, if so, does it have one or two of the solenoids?

Thanks in advance,

Colin

Dear Colin, I repaired my K50 by salvaging white solenoid from flash bracket on *ist dl. And there's another one at aperture block, white one. Cheers.

[nicolpa47]

Dear Colin, I repaired my K50 by salvaging white solenoid from flash bracket on *ist dl. And there's another one at aperture block, white one. Cheers.

Many thanks for that confirmation mlipovac. Up to now my K30/50 are ok, but I thought to acquire parts out of an old(possibly non-working) camera "just in case". Also dismantling would give me an idea of whether or not I'm comfortable with the job.

Once again, thanks,

Colin

[Mwellman]

Friday I found I had the dreaded aperture actuator failure. Oh nooooo! After watching the video, I found a set of JIS. scredrivers online and ordered next day delivery. They arrived early Sunday morning. Sunday is a work day so everything sat in the dining room until Monday. Called for a repair quote on Monday morning and was told, minimum $185 Cdn plus tax and parts. Nope. That is worth me having a go on my own and if I fail, I send it off and it still costs me $185. And I already had the screwdrivers. ( Get the right screwdrivers! What a difference from philips drivers) I watched the video again and then had at it. 56 minutes later my K50 is back together and working. While it is gentle work, it is really easy! Now for how long will it stay working? The real problem is that I also have a K1 so the 50 now gets very little use; And that is why it had the actuator problem.

My advice, if you are at all handy, fix this your self. You have nothing to lose and in my case, $180, less the cost of the screwdrivers to save. As a side benefit I now have a nice set of JIS screwdrivers, for the next problem or to tackle a lens i need to clean.

[reh321]

Friday I found I had the dreaded aperture actuator failure. Oh nooooo! After watching the video, I found a set of JIS. scredrivers online and ordered next day delivery. They arrived early Sunday morning. Sunday is a work day so everything sat in the dining room until Monday. Called for a repair quote on Monday morning and was told, minimum $185 Cdn plus tax and parts. Nope. That is worth me having a go on my own and if I fail, I send it off and it still costs me $185. And I already had the screwdrivers. ( Get the right screwdrivers! What a difference from philips drivers) I watched the video again and then had at it. 56 minutes later my K50 is back together and working. While it is gentle work, it is really easy! Now for how long will it stay working? The real problem is that I also have a K1 so the 50 now gets very little use; And that is why it had the actuator problem.

My advice, if you are at all handy, fix this your self. You have nothing to lose and in my case, $180, less the cost of the screwdrivers to save. As a side benefit I now have a nice set of JIS screwdrivers, for the next problem or to tackle a lens i need to clean.

When mine does fail, I plan to go all manual lens. I did that thirty years ago, so I should be able to do it now.

[clackers]

The real problem is that I also have a K1 so the 50 now gets very little use; And that is why it had the actuator problem.

.

Shouldn't be a problem now you have a white solenoid instead of green, right?

[ppohja]

I had a case similar symptoms as described here. The repairman said it was good enough just to clean the magnet. No change required. Now functioning perfectly.

[photogem]

I had a case similar symptoms as described here. The repairman said it was good enough just to clean the magnet. No change required. Now functioning perfectly.

Cleaning the magnet would really be nonsense because the magnet itself does not get dirty or would collect any magnetic dust or similar.

It is the horseshoe (which is magnetic, but not a magnet) which slides inside the plastic (cheap green solenoid) or teflon-like material (valuable white solenoid) and which gets stuck there in the green version.

Anybody who repairs a Pentax K30 or similar and would really say that cleaning or lubing would do the job has zero knowledge about what really happens there. If one takes the solenoid out and cleans it, that might help "for some time" (!) to better align it so that the fault doesn't occur for a short period. Because the horseshoe is magnetic, it does magnetise as well (like the tip of a screwdriver, if you touch a magnet). Taking it out demagnetises it a little bit so it "can" work a little bit again. Sanding the corners of the horseshoe makes the surface pulled towards the magnet smaller, i.e. less pulling force... BUT.... more chance that the horseshoe over time can tilt more and misalign! So not really a sensable solution of one
has better options.

The fault whith such methods is not solved yet. As I have heard by now and verified myself:

- The green solenoid works with a stronger magnetic force than the white solenoids which where made in Japan!
- The material of the white solenoid is superior:

If you (or any repairman) takes on the job to open the body and to unscrew the solenoid, one has done already 90% of all work needed.

The left-over 10% are to unsolder this green gremlin (1 min), built in the white angel and solder the wires back on (2 min), so why are people so
unbelievable mean and risk further damage or repeated work (those 90%)??? Lazyness? Meanness? Could be. Or sheer ignorance? Brick-headedness? Concrete-headedness? The funny thing is the very opposite of those words:

to be congrete about something (= white solenoid)

or

to remain stuck in congrete*....

or cheap plastic with a magnetised head full of fantasy .....

I don't mean you! Not at all. But those gobblers which talk a lot of nonsense or ... worse... make money with idiotic repairsolutions!
Or worse.... those who know but still........