Hope someone can assist in helping to figure out what might be wrong with this weed trimmer. I know it's not the best brand on the market, but it fit our budget. It's only about 2 years old. Ran fine the first year. Hubby went to use it for the second time this year and states that it's now hard to pull (to start). Said it doesn't have the smooth pull to it, sort of jerky. Also that it will run for awhile (maybe 10-15 minutes? he never gave me a clear answer on that) and then it will "lock up" --according to him. I've removed the plug and the pull cord will pull with ease. Put the plug back in and it's back to the jerky pulling. I did notice alot of carbon build up on the top of the piston, is that normal? Hubby will probably give me the what-for, when he finds out I've inquired on a help site! But he's so busy all the time I thought I might be able to help by fixing this myself (if it's not too difficult a task!) Thanks! mxmom

This is probably close to a 20 year old mower, it has worked great in the past and I keep it well maintained. Recently the muffler fell off, I have new parts coming. When I try to start it now, I choke it and it will start up and run for about 5-7 seconds, then it cuts off. I've let it sit for awhile & try again, same result. The gas is good (I drained and used fresh), oil is new, air filter clean. Any thoughts on what to do? I'll throw in a little carb cleaner, but more than likely it looks like a trip to the small engine store or a new mower.