Frequency of cooling

Recently transplanted a used deck into my existing Cavalier CS 64. It runs great, and actually gets down to temp at the setting of 1.5(about 38-39 deg) with 7 being the coldest. My question is about how long of a time span should pass between times the compressor turns on. Compared to my refrigerator it is turning on and off more often. I know that if I do have a problem it is probably the seal, or a really narrow tolerance of temp ranges, but I don't know what is normal... Oh ya, the machine is filled completely with beer and pop.