By Richard Cowan and David Lawder WASHINGTON (Reuters) - Congress narrowly averted a partial shutdown of the U.S. domestic security agency late on Friday night, but the forces behind the chaotic episode remain - fractious Republicans and House Speaker John Boehner's lack of control over them. In five to seven months, the federal debt ceiling will again be reached, and by October Congress must pass spending bills to keep the government running in the new fiscal year. Failing to deal effectively with these issues could have much more damaging repercussions - such as a broad government shutdown or a debt default - than a partial shutdown of the Department of Homeland Security (DHS). Some conservatives speak of ousting Boehner, but it is unlikely they can muster enough votes, while others made clear on Friday that they were willing to take big risks to score ideological points. Brinkmanship like this, reminiscent of 2013's 16-day federal government shutdown, was supposed to be over.