Squels under load, suspect the belt is loose, have removed the belt housing(plastic), don't know how to tighten the belt. Belt does't look worn. Also, I have no problem starting but must continue to hit primer 5 or 6 times once it fires and starts to avoid the engine from dyeing completely. engine once in a running state, runs up and down in RPM's, I assume i have to adjust the pulley cable to tighten the belt. please advise.