rickinmemphis 1 #1 Posted March 17, 2015 I need some help in trouble shooting an engine problem; I have a HH120 with a Walbro LME 34. I took the carb off and soaked it in carb cleaner stripped it down and boiled it in hot water and soaked it in carb cleaner again. I blew it out with compressed air after each cleaning. IT IS CLEAN. The throttle shaft has no play. Check valve is loose and bowl is set according to specs. I put a kit in it as well. It Starts right up and idles well. When I increase speed it is sluggish at the top end. It runs better at the top end with Main jet screwed almost all the way in not under load. When put under load it gets sluggish again Governor seems to be right and does not hunt. Any Guess? Share this post Link to post Share on other sites
Ed Kennell 36,011 #2 Posted March 17, 2015 Are you getting a good fuel supply from the fuel pump? Clogged screen in the tank fitting ? Share this post Link to post Share on other sites
rickinmemphis 1 #3 Posted March 17, 2015 I forgot to mention I put a Electric fuel pump on and slightly enlarged the fuel tank vent hole. Good flow to the engine. Share this post Link to post Share on other sites
psalms83:18 174 #4 Posted March 17, 2015 could it be electrical?? or maybe your air to fuel ratio?? or maybe spray pattern changed when u cleaned it, something lodged? Share this post Link to post Share on other sites
Ed Kennell 36,011 #5 Posted March 17, 2015 Check for good vacuum in the crankcase on the intake stroke. You probably know how, but cover the oil fill hole with your thumb to check. If no vacuum, you may have a clogged breather filter/check valve. Share this post Link to post Share on other sites
mey030 9 #6 Posted March 26, 2015 the statement it runs better on top in with the main screw almost all the way in ran into that problem on a twin cylinder opposed Briggs and Stratton they had put a electric pump on it was overpowering the inlet needle on the carburetor and flooding. if electric pump is used no more than one pound 22 pounds of pressure if more than that inlet needle will not seal tight Spellcheck struck again. I meant one pound or two pounds maximum pressure inlet needle diameter is large will overpower the needle Share this post Link to post Share on other sites
tbarnhart 240 #7 Posted March 27, 2015 Sounds to me like a restriction in the exhaust. Share this post Link to post Share on other sites
rickinmemphis 1 #8 Posted April 30, 2015 I replaced the Main Nozzle supplied by Mark Hare at http://carbrescue.com/intro.html . She runs like a Kitten. Thanks to all. Share this post Link to post Share on other sites