Active passive pool setup without preemption

I've currently got an active/passive setup of two servers within a pool using priority group. The problem is that it does preemption since one of the servers has a slightly higher priority. I want to be able to flip to server 2 and stay there indefinitely until it goes down and then revert to server 1 and again use that server till such a time as monitoring fails on it. This setup has no session management etc just http. is there an easy way to do this?