2008 Kubota U35-S Stalls motor when swing or multiple functions are used. I had a new hydraulic pump installed and pressures checked out by the hydraulic shop. They are thinking the motor is not getting enough fuel. Motor starts and runs great. I replaced some of the fuel lines and cleaned out the fuel tank (I found all kinds of stuff in it). I also replaced all the filters. Any thoughts on what could cause this. It has plenty of digging power but the second you swing the bucket it starts to stall.
My Cat was doing this as well. The motor wasn't getting enough fuel. Like you're saying, the tank had a bunch of crud on it. How did you clean the tank? Just draining it wasn't good enough for me. I did that a dozen times and thought it was clean cause no more debris was coming out when drained. But i kept having the same problem because the debris and diesel bugs sludge were heavier than the fuel and just stayed on the bottom of the tank. I had to use a vacuum pump and keep scraping the tank bottom with a rubber scraper. Keep putting a little diesel back in and sloshing it around, vacuum pump it out. Many times. Then used biocide. And replaced filters. Runs great, full power now.
Thank you for the reply. We pulled the tank and pulled out everything. The tank had a gas can nozzle in it and some wood. We used a degreaser cleaner and blew the tank out with an air hose. Then poured diesel in to rinse it out. It makes sense that something may still be in the tank becauce everytime we change the fuel filter it runs better for a little bit. I was going to take it to the shop but may try cleaning the tank again first.
We had a similar issue with our 2001 KX121. The fuel/water separator was clogged up with gunk.
I've had a rash of plugged water separator filter heads, on all brands here. Fully disassemble the water separator assembly and shove a wire all the way through every port to ensure no blockage.
Thank you all for the suggestions. We had some one go over the fuel system and everything was working correctly. They then checked the hydraulic pressures for individual functions and found most the pressures were way to high. The machine is running much better now.
What exactly did they do? I’ve got a 2011 U35 doing the same thing and I’ve checked the whole fuel system. Believe it’s hydraulic related