I went to one of these liberal arts college. They all (typically) have science and math departments. Engineering typically doesn't fall under the purview of liberal arts (though pure science and math certainly do). The problem tends to be availability of upper-level electives if you actually care about learning certain topics and don't want to just complete the requirements. Also, your exposure to research opportunities are typically external to your own institution (there are exceptions to this). I'd say the required courses in the first two+ years are a better experience than large research universities though.