I just picked up a used Lazer Z HP 52" from a home owner that is in very nice condition. When I received it, I went through it and changed the oil, oil filter, air filter, etc. I sharpened the blades and had at it. Ran like a fine machine the first week, and second week. I started to mow this past week and ran out of fuel. So I switched it over (has dual tanks) from the right tank to the left tank. Initially it ran fine (probably 15-20 minutes of cutting and picking up leaves) and then it really lost some power. It is kind of hard to describe but just acted like it did not have enough power to get up a small hill and not enough power to give a good cut. So I check oil, it is fine....then I start thinking about the fuel tanks. I refill the right tank, restart it and let it run with the choke on for awhile and...... now it is running perfectly. 1. Why don't they put two fuel filters on these machines with dual tanks? 2. Do you think it is a bad fuel filter or is it a bad line coming off of the left tank? Any suggestions as to the best way to diagnose the problem?