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Bought a Homelite HB180 and the Walbro carb came loose from the isolator block. Fixed that and then the cylinder which was held in place with three screws came loose from the crankcase. Got rid of the gaskets and sparingly applied RTV to the mating surfaces and reassembled using new hex washer head fasteners and #242 Loctite. The gas filter in the tank tends to plug up with who knows what and must be replaced regularly. I then bought a second Homelite blower, a vac-attack model and the gasket between the isolator and the cylinder head turned to mush and the Walbro carburetor came loose. It would start and run on fast speed if I used Ether but would not idle. The cylinder also came loose from the crankcase. Replaced the gaskets with soft aluminum sheet stock and reassembled using a sealer. Problem solved. Bought a Ryobi string trimmer and the Walbro carb and isolator came loose from the crankcase. This was retightened and the problem was gone temporarily but later resurfaced. Poorly engineered fastener joints. Bottom line, these machines are not engineered very well. The two cycle engine vibrations combined with the combustion heat and the poorly designed thick and soft gasketed joints combine to produce a loose and leaky system which gives a lot of grief to the customer. The secret is to treat the fastener like a spring and that spring keeps the joint tight and together as long as it has tension applied. Once the tension is lost the joint is loose and leakage begins and the rest is history. In order to keep tension in the fastener joint the gasket must be very thin and hard so as not to compress resulting in a tensionless fastener and loose joint. If there is a polymer product sandwiched in the joint then there must be sufficient compressible strength in that polymer to support the axial forces of the fastener. If there is not then the plastic component must have a metal standoff lining the fastener hole to support the fastener joint compressive loads. When they designed these units they did not care about any of this. Thay were concerned about a competitive price and profit margin. Of course all of this is just my humble opinion.
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