Why do conservative engage in this apparently hypocritical behavior?

First, they claim we need to balance government budgets in order to instill investor confidence in the American economy and show we won't default on our debts. Then, they support not raising the debt ceiling, threatening to prematurely hit that debt default threshold. Is there some logical explanation for these apparently hypocritical stances? Do conservatives really believe we can make a $1.65 trillion budget shortfall disappear over the next 2 and half months, when Secretary Geitner's accounting tricks run out?