I have had this hedge trimmer attachment now for almost 4 years. Never had any problems except for some of housing screws falling out. No big deal. Was using it last Saturday and noticed some smoke coming from the housing and it got a little worse. I finished the job and noticed that all four housing screws were gone. Bought four new screws, added some red lock tight and installed. Added grease, now it doesn't work when all screws are tight. If I loosen the screws about 2 rounds each, it will work but the grease comes out and the screws will fall out again. What is wrong with it? Any suggestions. Paid $290 for it. I'm a little afraid to take it apart. I have a parts diagram. It's model 99944200590.