When you say links are you talking about breakfast sausage links (small diameter) or are you referring to summer sausage size?
I've done several batches of venison summer sausage in my FEC100 and they usually take about 7-8 hours. I start out at lowest temp setting (140) with the door cracked open to keep the smoker temp running around 100*. You want to keep the smoker temp down until the casings dry out so they can take on the smoke. Once the casings are dry (about 1 hour) I close the door and over the next serveral hours gradually increase the smoker temp up to a max of 180. Try to avoid getting your smoker temp much higher than 180-190 since you risk melting the fat in your sausage which will dry them out. You'll want your meat temp to reach around 156 to be done.