On one of my walk behind mowers, an Exmark Viking 52" we are having problems starting in cold weather. It has the kaw. FC420V,14hp. I use the release spring under the mower but it still about breaks your arm when it jerks the rope out of your hands. I was told to switch to a 10W-30 weight oil instead of just 30 weight. They told me that the auto decompression spring is not heavy enough to pull through 30 weight oil when cold. I have been through about 6 ropes in the past couple weeks. I also figured out that the eyelet on the starting housing was wore through. So you have to order a whole new assembly just to replace an eyelet.. So does any one know if a 10W-30 should cure my starting Blues.