My 2006 cat 430E backhoe , sometimes the tachometer sticks at 600RPM and when this happens the engine sounds a little different like a pinging ? And when it doesn’t happen everything runs great idle’s at 800rpm and runs good.
I don't think the tach is the problem Is some hydraulic function valve still partly engaged? I'd guess/hope the engine is just lugging down a little more because it's working harder than it should at idle? Figure out where the load is and make the load go away. Hopefully it's not an injector sticking open, or a bearing siezing up, or any number of other things, that's why I'd at least figure it out sooner rather than later.
I thank you , I know there’s a hydraulic fluid leak in a cluster of valves under the tractor but bin putting it off because it’s so hard to find the leak ? But I better get to it , thanks again
I don't think a small leak is your problem. It could be related to the problem if it's pilot controlled hydraulics on a pilot line, I don't know the Cat generations.