MINOLTA Hi Matic E service guide/questions

[rogalxxx]

Hello everybody.
Just got my Hi Matic E and I've put in x2 1,4v batteries.
At first the check light went on and it measured, lit the green light and shutter worked and everything looked all right.
Than, after a couple of hours the light sometimes goes on than becomes dimmer and dimmer, and no shutter 🙁
Checked battery with meter and it was 2,7V, checked the battery contacts in the battery well and could not get consistent results. sometimes it was 2,7V sometimes 0,1V.
I guess the wireing is at fault. There is some leakage in the battery compartement. not much, but it shows inside of the camera.
Can anyone give me any clues on how to disassemble the minolta hi matic e so I could fiddle with wires?
I'll try to add pictures in a moment.

 

[rogalxxx]

battery contacts

wireing

a tiny copper plate was here. fell off due to corosion when I took off the bottom plate.
does it have a purpose? ground connection to the chasis?

 

[rogalxxx]

another strange behaviour I noticed:
this morning the battery worked ok. for 10 seconds. Than it started to fade. Tooka out the battery, bhecked the voltage-2,65. Than checked the voltage again 10 mins later-2,87 .
These are 2-day old batteries with a lot of shelf life left!
can the camera "drain" batteries?
I'll get some silver and alkaline batteries and see what happens.
Still I'd appreciate a rough guide for opening the Minolta Hi-Matic E. I know there was a printed guide on ebay somewhere, but not anymore.

 

[Robin P]

Persevere, it's a wonderful little camera when it works! I fitted mine with a 3V lithium battery.
A quick read of this page should tell you all you need to know.....
http://filmphotographyproject.com/content/reviews/2012/09/minolta-hi-matic-e-camera

 

[rogalxxx]

Got myself a handfull of different batteries.
What worries me is: if there's current flowing constantly to the light meter, would it cause additional damage to the corroded wires and solder points? Thus the battery drain.

 

[rogalxxx]

edit: moved to the right section

 

[02Pilot]

A copper plate was probably there as a chassis ground or at least to ensure a proper electrical connection between parts. I don't have a guide to help you getting inside the camera, but once you do I suggest you start checking continuity through the whole circuit to see just where you have good connections and where you don't. For now, you might check to see if you've got voltage bleeding into the chassis or elsewhere (note that some cameras use positive ground).

 

[rogalxxx]

yes. there seems to be voltage bleeding. i'm at work atm but as soon as i get back home i'll check again.
thank you for your input. I'd really love to get that beauty working again

 

[rogalxxx]

ok, here's what i found out so far:
2xzinc-air
fresh: 2,94V
After 10s metering in camera: 2,69V
every 10s out of camera : 2,74V
2,76
2,89 and so on

2xsilver ox
fresh: 3,17V
After 10s metering in camera: 3,14V

1xlithium
fresh: 3,06V
After 10s metering in camera: 2,98V

Shutter works with every battery. Check light and in-viefinder light turns on only with zinc air, and lithium battery. Every time the check light gets dimmer and dimmer. (that's when i check the voltage second time)

 

[rogalxxx]

(-) to chasis

(+) to chasis

 

[rogalxxx]

well, I managed to remove both top and bottom plates, than unscrew lens plate. whole thing would not let go without removing additional small parts and springs inside. I kind of panicked. The good thing is, i managed to put the whole thing together without loosing a single screw. Maybe I'll make a video showing where I got.

 

[rogalxxx]

not sure what I did but after putting everything back together it kind of works better!
3V lithium battery and 2x1,5V alkaline seem to work best. Question is: should I compensate ASA for b&w illford 400 film?