There is a Loitz in the old region of West Pomerania (Vorpommern in German) and this town is about 28 miles north of Gross Varchow, of the old Grand Duchy of Mecklenburg-Schwerin.
There is also another very small town of Loitz in the old area of Mecklenburg-Strelitz and is about 14 miles southeast of Gross Varchow.
Here is an old 1897 map showing West Pomerania (Vorpommern) and Mecklenburg.http://mitglied.lycos.de/pomerania2/images/pomue2.jpg
Loitz, West Pomerania is on the far left side of the map near the mark 54 on the left border. Then to locate Gross Varchow, (not shown on the map but is near the town of Molln), drop straight south and cross the border into Mecklenburg.
How certain are you of the spellings you had of Grossen & Varchow and Loltz? If you have any question you could post the documents that show these towns to this message board as an attachment so others could help you with the spellings or translation.