Cygnus the Swan..Welcome to MBc. I don't know what troubles you're having with your engines, but we have an excellent search engine that will be a big help. Almost everything that can be a problem has been asked and answered already. Be sure to read all of the sticky notes at the start of each Forum. I don't know what engines you have but they sound like 2-Strokes; so, if all else fails, post your problem in the 2-Stroke Forum. Good luck.
PatrickW