[olivexrush]

i recently bought a pentax 6x7 MLU online
It was in great condition, and came with a 150mm lens
However my first roll came out totally blank, so i immediately tested the shutter to find that it wasnt opening at all
Bought a new battery, still nothing. But after a couple goes of testing the shutter, it suddenly started opening, only to then stop after about 10 more dry fires. After another 10 fires it started opening up again, which it still is doing now.

Absolutely everything else about the camera works perfectly.

I havent been able to find any conclusive examples of this issue online, the guy i bought it off is adament that it never had this problem while he was shooting it, but he also only used it for 2 rolls before selling it to me. Someone on reddit suggested that the shutter grease has melted, causing it to work again, which makes sense considering it was a 40 degree celcius day.

I dont want to have to pay for a repair when i bought it just last week, so i really just need some insight into what the issue could actually be before i make a decision on whether i should attempt to return it or not.

[gofour3]

Welcome to the forum!

The P6x7 is not designed to dry fire the shutter unless special procedures are followed. Here is a link to a copy of the manual, it will guide you through resetting the camera and so on.

https://www.cameramanuals.org/pentax_pdf/pentax_6x7.pdf

Phil.

[Silent Street]

The shutter and winding mechanism are two different things, but they are inextricably linked in operation: the shutter will not fire a second time unless the frame is wound on (exception: those Pentax 67 cameras with factory-fitted multi-exposure facility available). As Phil, above stated, dry firing requires a bypass key in order to test and observe the shutter action without using any film.

I am inclined to think the camera has been set aside too long with the shutter cocked, leading to laziness of the magnet. There is an advisory of sorts about this in the 67 owner's manual, additionally to storing the camera with the shutter speed dial on any setting other than a marked shutter speed or X (Bulb is fine); storing the camera with the dial on a shutter speed can also lead to inaccuracy of that or other speeds.

Prolonged cocked, idle setting can cause the shutter magnet to stick. This can manifest as either the shutter randomly failing to fire, or firing intermittently (even an entire roll being exposed), giving the impression there is nothing wrong, but which highlights an uncomfortabel truth: it obviates a degenerative problem that will eventually require repair.

High temperatures present their own problems. Where I am it is regularly 45°c in open shade, and nobody goes out there, nor the dogs! I never use my own cameras in +40°c heat; doing so can melt the seals around the camera pack, the prism, distort the focusing screen and as you have been told, affect the internal lubrication, which is miniscule in quantity, abundant in application, and essential for smooth function. It's like clockwork inside a 67!

As much as I would like to agree with the seller's statement to you, I don't.
A brute test is worth doing at this stage to be suss things out.
Grab a couple of rolls of cheap film, and whip these through the camera using as much continuous shooting as you can. During this test if you notice the shutter is not firing or firing intermittently, the proof is there that a fault exists. If you cannot get it to fire again after noticing the stop, unload the film (release both base clasps, open the back and remove the film, avoiding any contact with the shutter), and that is the end of the test.

If that test of 2 rolls has had to be aborted, then I would recommend the camera be returned to the Seller on the basis that, in my view, you are looking at a degenerative fault that is not a once-off, but going to become progressively worse in time.