We've had a whole dearth of these posts lately so I thought I'd do a pictorial so we don't have to keep describing it with too many words that end up sounding confusing. One picture is worth a thousand words, right.
This applies to all Mausers - German, Check, Yugo, Persian, Turkish, South American, Swedish, Chinese, whatever, 93, 94, 95, 96 & 98 patterns. This is an -03 Turk ('98 pattern) from my future sporter projects bin.
OK Quick Review of function.
Here's the Mauser Safety in the FIRE mode. You can operate the bolt and fire the rifle:

Here it is in the LOCKED mode. You cannot operate the bolt nor fire the rifle:

Here it is in the SAFE mode. You can operate the bolt but not fire the rifle:

It is important that the safety is in the SAFE mode to remove or disassemble the bolt.
In this mode the cocking piece is held a distance away from the end of the bolt body:

Oh crap - mine looks like this:

And the cocking piece is touching the bolt body:

Woe is me, I guess I need to scrap it and buy a new rifle - Sigh! Not to worry - it's easy to fix. Simply hook the cocking piece on the edge of your bench like this:

Pull down to compress the firing pin spring some more until some space appears between the cocking piece and the safety here:

Then you can raise the safety to the SAFE position and let the cocking piece rest on the safety.
If you just cant get the safety to work right, it is probably because these two surfaces are worn or maybe have a burr. Carefully stone these surfaces smooth and square (it'll improve your trigger pull too!)

This causes excess interferience here, where the safety engages the cocking piece. You can see that this one has rough marks. It is difficult to move. Stone this surface smooth and burr free and grease it well with some thick grease, and all should be well.

Good luck and happy shooting.
Jeff S.Roy Mcleod
Jeff S, Great post and photos I have tried everything and have two mauser 98 safteys that do NOT work.
With this PROBLEM, is the answer to cut back on the front sear on the cocking piece or the front camming
surface of the cocking piece?
Need HELP Roy Mcleod
Probably the sear and cocking piece interface has worn a bit. You're better off not screwing with those surfaces, so to answer your question, Yes. You can cut a slight taper on the front edge of the cocking piece like this:

Take it slow, only taking off a little bit at a time and fully reassemble each time to check your work. When you put the safety on, it should pull the cocking piece back a bit. If you take off too much off, you run the risk of making it so that if you pull the trigger with the safety on, then flip the safety off, it will fire without touching the trigger. That's a good test once you get it working. Put the safety on, pull the trigger, take your finger off the trigger, and take the safety off.
Hope this helps