Sewing machines and sergers need regular service, especially in Arizona they dry out and need cleaning and lubrication. Newer machines often are not set right from the factory and need tensions and feed balance set. Regular service depends on how much it is used, if a lot it might be 6 months, rarely used every year or two.
Besides having your machine serviced regularly so it doesn’t break down, these are the things you can do to keep it in good shape.
Change the needles often, at least every project. If it is making a popping noise it dull and past time it should have been changed. It is especially important if you have a needle threader on your machine. If you having trouble with your serger change the needles and correctly rethread the machine.
Needle screws should only be tightened finger tight. Over tightening causes damage to the screw and the clamp. I have seen people strip the threads, damage the needle screw so much the needle will not say in and even crack the clamps. Especially do not use a screw driver to tighten the screw. The T handle screw driver Viking gives with the machine can allow you to WAY over tighten the screw.
Clean the machine, lint must be removed. Do not blow it farther into the machine. It should be vacuumed out or with a lint brush. Be sure to remove any lint rings on the needle bar and between the feed dog teeth. Lint is abrasive and drys out the lubrication. Enough lint packed in the feed dogs can cause feeding problems wear out the needle plate from the bottom, cause problems with the feed mechanism. Lint packed into the bottom needle bar bushing can wear out the bushing and bar. I have fixed many machines bound up by cleaning the lint out. Sergers generate a lot of lint cutting the fabric.
If you machine has a bobbin sensor it will not work if there is lint around the hook and bobbin case. If the sensor stops working it almost always is because lint is blocking the sensor.