T190 loses power, runs rough, starts smoking when worked hard

[Threeway]

2005 Bobcat T190 with Kubota v2003t. Engine temp gauge never reads over 1/3 all belts recently changed and adjusted. After about an hour or 2 depending on ambient temp and actual workload, unit will start losing power, minor black smoke and stalling on quick movements. At that point if brought down to Idle it runs rough and cannot even lift arms or bucket.
If shutdown and left for 10 mins runs right for 20-30 mins and repeats problem. We thought maybe turbo flow was slowing when hot.. but not the case. Been doing some more troubleshooting and narrowed it to fuel delivery I think. Changed filters with no real change. Last time while running i brought down to idle and grabbed a garden hose and started SLOWLY misting only the injector pump with water. The response was almost immediate within 10 seconds the idle smoothed out and after 30 seconds of misting it full power was back, I returned to working for 45 mins before it started again. Any Ideas?? Thanks in advance.

 

[heymccall]

Black smoke is lack of air or too much fuel.
Air filters new?
Intake hose sucking shut?

On all of my kubota engines, a fuel restriction shows a a miss, loss of power, and, most importantly, white puffs of exhaust when the engine is missing.

You didn't say how many hours, but if over 10 years old or over 3000 hours, there would be a good reason to have the injectors tested, both for pop pressure and spray pattern, especially based on your symptoms.

 

[Delmer]

I'd start with the simple stuff, like any rubber fuel lines, or filter gaskets, or cracked or loose fittings, or banjo bolts with screens inside.

The way it gets worse after such a long time running makes me think it's more a rubber hose or plastic component leaking air.

I'd even tee into the supply and run a line to a vacuum/pressure gauge in the cab, and check the return for bubbles before touching the injection pump.

 

[Threeway]

2600 hours.. air fliters fairly new but same issue when they were new i have not looked at intake tube, however when it was acting up we pulled the turbo charge pipe off the intake and there was plenty of pressure ..purchased with 2200hrs from a rental house.. I believe they were chasing an overheat issue. we found a few things that helped for sure.