How cold is it outside, and is the truck engine cold? I couldn't start my truck the other day, and the pullstart was doing the yo-yo thing. I took a hair drier to it for about fortyfive seconds and it started right up.The thick greasy substance is unburnt oil that has seeped out to the exaust tip. If that doesn't work, try tipping it upside down and pull the starter to get the fuel and extra oil out of the cylinder. Other than that, I will think on it and see if I can come up with anything else.