Lift arm has little or no down pressure. also detant sticks on peddle. A tap with heel or toe releases it. This happens 2 or 3 times a day but the no down pressure is constant. I pulled the spool and everything appeared normal except the detant spring was slightly deforned so replaced the spring and it helped for about 3 hours. Does anyone know what the problem is?? 2 shops have told me they have never heard of such a thing. Alll suggestions appreciated. --Grant--