Problems with Mccullough Trimmac 210 petrol strimmer

I bought a Mccullough Trimmac 210 petrol strimmer off eBay. The owner said it hadn't had much use in recent times so I changed the fuel. It said to use 40-1 so I put 100ml of oil,which I got free with another petrol tool, into 4 litres of petrol. It started ok and worked for 5 mins but then started making slightly unusual noises. It eventually conked out and doesn't start now. PLEASE HELP. Hope I haven't f---ed another strimmer up.
Andrew McGowan

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.