I was mowing today on my 2004 20/52 Fastrak and my drive belt came off and tore the plastic fan blade off the Left Hydro. Not sure why it came off but all the idler pulleys are rotating OK. I have never replaced this belt so when i replace the fan blade I am going to put a new belt on. 2 Questions What is the Part number of plastic fan blade on top of the left hydro pully? I just mow my property (3 acres) so can I mow without the fan blade on until I get the new one or will the left hydro overheat without the fan blade? I have changed the hydro oil and filters several times.