Your Husqvarna 345 chainsaw requires regular maintenance and tune-ups to achieve maximum performance. These chainsaws operate at high speeds under tough conditions often in hot weather. With all this abuse, keeping your chainsaw clean and maintained will improve performance, but it will also extend the life of your Husky.
The air system is one of the most crucial parts that you must check regularly. The air filter, a foam pad, needs to be cleaned regularly with soapy water. When it gets dirty, replace it with another Husqvarna chainsaw air filter. On the other end, the muffler needs to get rid of the toxic air. So, monitor your muffler and clean it out every 60 to 90 hours of operation. The spark arrester screen helps prevent fires, so if this is too dirty to clean, replace it.
Spark Plug Specs
During every tune-up, check the electrode gap on your spark plug to make sure it's clear of carbon build up and properly gapped. The electrode gap on the 345 must be set at .5 inches to fire the spark properly. You can check this measurement with a spark plug gapping tool, or, if you can't find one, a credit card is usually about the same thickness, though not as precise. If your plug is looking black and dirty, replace it with a new one, which is more simple than trying to clean it and check the gap. Replacement plugs for the 345 must be NGK BPMR 7A or Champion RCJ 7Y.
Fuel and Carburetor
Drain the fuel tank and rinse it out, and thoroughly clean it during every tune-up. This will prevent build-up from blocking the fuel filters and entering the carburettor. You can rinse out the tank with a little unmixed fuel, about 1 to 2 tsp, and swish it around for about 10 seconds. Dump the fuel out and scrub it with a brush and rag. Pull out the fuel filter and replace it with a 345 fuel filter, which you can buy from your Husky dealer. If your carburettor is starting to get a little dirty, start the engine without the air filter on and the choke open. Squirt a little bit of carburettor cleaner into the open valve and let the smoke burn off.
After you've cleaned the air and fuel systems during your tune-up, readjust the carburettor screws. These screws help balance the air and fuel mixing at different speeds in the carburettor. Cleaning the fuel and air system will likely cause a small imbalance in these two, and getting top engine performance will require you to manually set the carburettor screws. Turn both the low and high speed screws in clockwise until they're fully seated. Turn them back out counterclockwise one full turn. This is the factory setting and you can fine-tune it from here. Don't over-tune the carburettor, especially the high speed screw, as you can damage the entire engine. Leave these adjustments to a qualified professional.