I kinda wish people would stop bad mouthing the Nikki carburetor. I have work on them for years. They are one the easiest carburetors to clean. Most problems are ones that get introduced by techs that don't understand them. Yes that lean burn issue is in some of them but why they have removable main jets so the tech can resize as needed. Yes the fuel transfer tube gasket can be a problem if you don't inspect it before installing for bad places. Jet o-rings do get loose causing surging. But the main culprit is setting the idle speed too low and the governor simply closes the throttle too much cutting off the fuel supply.
All carburetors have their problems but when you know what you are doing most problems are resolvable. But it does takes a good mechanic and not a fly by night mechanic (part replacers and guessers) to resolve these problems. I had one that spend over $300 trying to fix his mower to only bring it to my shop where I found it was only a $0.50 wire terminal that was bad. He was just replacing hopiing to hit upon the problem.
And considering the OP mower is 17yrs old what does he expect a new mower that don't need multiple repairs. Heck most operators and owners never do to anything to mowers other than abuse them until they refuse to move or run. I just finishing up on a Hustler Fastrak that has been abused. The owner even she knew it was leaking lots of oil, she ran it until it locked up. Now they are complaining it is cost $900 just to get running again. Even with the repairs it will have a short life for the next repair will be a new engine which probably will not get. They have bent numerous metal frame and deck parts hitting objects.
