So my dad is getting up there, 86, so he doesn't cut wood anymore, just pays a guy to deliver it......so he had an older 021 he gave me. I have a Makida 6401 but wanted to use this 021 for limbing and other small stuff. He says it's been at least two years since it has been started. I drained the old gas mix, put new in, and put a new plug in.......it'll start but is hard and as soon as the trigger is pulled dies out. I adjusted the idle higher and it will stay running but as soon as the saw is raised it dies out....what could my problem be?