Happened to me also. Leaving Fresno, on the upwind; the pump continued to pump. I also pulled the breaker, did a circle to land but fortunately got three green. Landed, taxied to the FBO and the nose wheel well was well washed down with fluid.  The nose gear cylinder pushed the deformed washer retainer forward and blew out the seal.  I ordered a new assembly, installed it the next am and departed for the northwest to home.  The newer cylinders have a machined aluminum washer about 1/4 inch thick. The original seal washer looked like a fender washer. Not very substantial.  So check your nose wheel actuator cylinders for a gold colored retainer washer behind the snap ring. If it is gold; I recommend you replace it. It will blowout some day.
 
Bob Smiley
N94RJ