Oil & Fuel TC 40 D stalls under heavy load and will not restart

brianb33 · Oct 2, 2013

I have an ongoing issue with (I think) fuel starvation and/or air in fuel lines. My TC40D is sluggish to start when "cold" and will not immediately rev up above about 2000 rpms. After it runs a few minutes it will reach higher rpms. I have had ongoing problems with it stalling under a load and fails to restart afterwards unless it sits for several hours. Sometimes there is a large air pocket in the fuel filter housing after it stalls that was not there before starting the tractor. I have to engage the PTO with mower attached at 1100-1200 rpms to prevent it from stalling. Needless to say this is hard on sheer pins, and it is hard to get any work done when I have to let it sit overnight to restart it after it stalls. I have the same problem if I shut off the engine as well. I have cleaned the fuel tank, replaced all fuel lines, replaced the fuel filter, and tried bleeding the fuel system to no avail. I have even tried bleeding the fuel injector lines (the ones I can reach) but it still will not start unless it sits several hours. I'm thinking I have fuel starvation issue that causes the sluggish start and a slight leak somewhere in the fuel system that is introducing air that causes it to stall or fail to restart that eventually self-bleeds after it sits for several hours. Any ideas on the most likely places to start checking for constriction/leakage?

jinman · Oct 3, 2013

Below is an illustration of your whole fuel system showing details of the hose routing and the filter installation. What is normally missed on our tractors is that we have a fuel lift pump. It's after the filter. It draws fuel through the filter and its output goes directly to the top of the injector pump. Therefore, if the fuel filter ring seal, hose clamps, or even the lift pump itself is drawing air, it gets drawn into the system and fed right to the injector pump. If you are seeing air at the top of your fuel filter, it has to be coming from one of the sources above. In your case, I'd be tempted to fill the fuel tank so it will gravity feed and bypass the fuel lift pump by going straight to the injector pump from the output of the fuel filter. If that clears things up, then you know that the lift pump is sucking air from somewhere and you can keep looking for it. Several people have discovered that the fuel filter ring nut and seal are not seated properly, but I'm not saying that's the case on your tractor. I'm just saying that there has to be an air leak for air to appear inside your filter.