JX75 Carburetor issues

[stlspartan]

I have a JX75 that I purchased in the early 90's and is generally great shape. It has a Kawasaki FC150V engine with a Mikuni carb. Ever when new it has not run until warmed up, surging a lot and stalling when the blade was engaged. To me, it seemed like a fuel problem. When new it went back to the dealer for the issue and they cleaned the carb and got it running better, but it has never been eager to rev up or pour out the horse power. Last season it got worse and I disassembled and cleaned the carb but it didn't help. As a test, I ordered a $20 Mikuni clone and installed it before taking it out this season and now it runs like a champ, better than it ever has.

So, is there a good reason to buy the real Mikuni for $125 or can the original be easily fixed? Gas isn't coming out the overflow tube and fuel flows freely from the gas tank. When searching, I've found others who just had a 'bad' OEM carb. What would you do?

 

[Scrubcadet10]

Old original carb may just need a good soaking, or a ultrasonic cleaner.

 

[Born2Mow]

"Runs, but without power" type problems are typically low float level and/or clogged low-speed passages. Or it could be you simply got a California model that's jetted leaner. All of these issues work against the engine getting that last 5% of fuel needed to "run strong".

Spend 30 minutes comparing the liquid levels inside the float bowl AND the low-speed jet sizes between those 2 carbs. I think you'll get a good insight into why or how the engine is being starved for fuel.