Nikkormat DOF preview button to fire shutter?

Hi,

I'm trying to figure a couple of things out for a friend that owns a

Nikkormat 35mm body and Nikkor H.C Auto 1:2 50mm manual focus lens.

When aperture is set to F/2 it is only possible to fire the shutter by

pressing the DOF preview button next to the shutter release. Anything

above [f/2.8 up to f/16] the shutter release button triggers fine.

All I can guess at the moment is that this body was intended for

lenses f2.8 and above and requires stopping up [?] to meter for wider

apertures.

Any advice would be greatly appreciated.

You have something wrong with the camera.

For over 30 years I have used lenses with f stops of 1.8 and 2 on my two Nikkormats. No problem. They were built to handle them.

You probably need to get the lens link mechanism cleaned.

Good news. The camera is usually fixable.

Errol