Terex hr 1.6 bogs down under hydraulic load

[Clayton Wright]

I have a 2006 terex hr 1.6. Machine starts good runs good idles smooth until it gets good and warm. Then if u pick the boom up pull the crowl in or pick the blade up when it reaches as far as the hydraulic cylinder can go Itl bog motor down bad. Even if I reach out an pick up a rock Itl bog like its gona die or as if it’s running outa fuel. But my fuel filters an stuff are good. Don’t know fuel pressure as I don’t have a gauge that reads accurately. Does this sound like a fuel problem?

 

[Ronsii]

Since you mention just lifting a rock boggs it... then my first guess is fuel related.... or something to do with the throttle governor.... could be a few other things too...

 

[Clayton Wright]

Ok ima replace filters again. And another thing when it’s bogging doen it blows a black puff of smoke but doesn’t like roll a steady black smoke if that makes any difference

 

[Nige]

Your symptoms sound like the pump is not getting a command to destroke when the cylinder reaches the end of its travel. I have no idea how that system works on your specific machine but that sounds like what's going on.

 

[Clayton Wright]

Even with it doing it when I go to pick something up? With no hydraulics at there end?

 

[Nige]

I'm at a disadvantage here not knowing the machine, but are there any places in the fuel lines such as the head of a fuel filter or a banjo bolt fitting (injector pump inlet is a favourite) that might contain a small screen that is partially blocked with crud..? Or even a small passage in the fuel filter head that can block.? Changing the element is only part of the story.
Does the fuel tank have a drain plug or drain tap..? If so have you tried draining the water and crud out of there as a start.? If not the fuel would have to be suctioned out of the tank so that it could be cleaned inside.