Yes. On many 146s a narrow strip of the ink window stays visible with the cap fully screwed on. The length of the window was altered several times over the production years, so pens of different vintages differ on this point. A visible edge of the yellowish window about a millimetre wide is therefore no sign that the cap is not seated properly or that cap and barrel do not belong together.
Cracks in the cap, common on pens of this period, are another matter. They usually run from the cap lip to the first ring and appear when the material shrinks over the pressed-in metal ring and comes under stress. Left untreated, such a crack widens further every time the cap is screwed on and off. It belongs in the hands of a workshop that specialises in old writing instruments; home repairs with glue do the pen considerable harm and can scarcely be put right afterwards.