I have a Craftsman YT4000 Model 28857 with a Briggs 24hp 46in cut. After it sits a week its super hard to get started. When it fires it sounds like its not hiiting just right. Then it takes off and runs and starts great until it sits again. I changed the plugs and cleaned the filter(air). It still didn't improve. Any suggestions????? Also, is there any Lubrication ports for the mower deck? I don't see any. If so, what kind of lube to you use on the deck?