Minolta Himatic 7s aperture issue?

[usagisakana]

I recently bought a himatic 7s from ebay, and it was in fairly poor condition cosmetic condition, but i've cleaned it up quite a bit, replaced the light seals, bought film etc, was all ready to go shooting. But I've noticed what I think is something wrong with the aperture- the shutter seems to be accurate at all speeds, (at least as far as I can tell), but when I use a bulb exposure and vary the aperture, nothing seems to change... the aperture seems to stay just short of wide open, no matter what the setting. Am I mis-observing this, or is there something wrong with the aperture setting? If there is, is there any way of fixing it? any help would be appreciated.

 

[greyhoundman]

The blades need cleaned. They are stuck with old sticky oil.

 

[usagisakana]

righto, anyone got any good links for instructions as to how to do this?

 

[FallisPhoto]

righto, anyone got any good links for instructions as to how to do this?

It can be done, but the Hi-Matics are one of the most difficult of all rangefinders to work on. Only the Canonets are harder -- sometimes. Personally, I'd get a new Hi-Matic. I did it once and I don't ever want to do it again.

 

[usagisakana]

Hmm yes that seems to be the consensus after doing a bit of reading. It's just a shame because I've put so much effort and money into this, but if I can find another one cheap I guess that's the way to go. Alternatively I could see it as- It's stuffed if I don't give it a try, may as well? if so if anyone could direct me somewhere for instructions, I may as well try, got a lot of time on my hands because uni is out.

 

[FallisPhoto]

Hmm yes that seems to be the consensus after doing a bit of reading. It's just a shame because I've put so much effort and money into this, but if I can find another one cheap I guess that's the way to go. Alternatively I could see it as- It's stuffed if I don't give it a try, may as well? if so if anyone could direct me somewhere for instructions, I may as well try, got a lot of time on my hands because uni is out.

There might be someone here who can help you: http://www.kyphoto.com/cgi-bin/forum/discus.cgi?pg=topics

 

[Frank Lambert]

I just finished fixing a similar problem on a Minolta 7S. The shutter and aperture were both sticking. I removed the front lenses and squirted Ronsonol on the shutter blades. Everything freed up but it took doing that same thing over and over, letting it dry out between re-soaking the blades in both the shutter and diaphram. I finally blew it out with compressed air and it seems to be working perfectly now. I used the Ronsonol sparingly and tried not to get too much inside the works. I also used a micro fiber cloth to "dab" the excess off as I went. I felt that would help remove any diluted oil that might remain after the ronsonol evaporated. Anyway, just thought I would let you know what "cure" was used here...

Frank

 

[ully]

Well, I just got done unsticking the blades on mine but now I notice it does the same thing, they open but only to wide open.

 

[ully]

Well, since my last post I went back into the lens and put another drop of lighter fluid on the stuck open aperture blades and they popped out. I exercised them for awhile and now everything is good. Now for the meter.

Cheers