I inherited a 1987 WH 108-5 rear engine 8HP Riding Mower. I cleaned it up and got it running but there is a fuel leak from a little screen under the choke. I don't have a parts catalogue to identify this part, but it leaks quite a bit. Any ideas? Any assistance will be greatly appreciated. I sent off for the parts catalogue and the owners manual but they won't be here for 10 business days it says. HELP please...