It has started to use a lot of lubricating oil - refill every 10 mins. Can't tell if the O ring seal is damaged but the one on the inside of the cover plate seems very flat so may not be providing a good seal.
Its a PP - PWR1800CSD.
I tried ringing PPs helpline, who helpfully said they didn't do spare parts!!
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix chainsaws.