3406b Not making hardly any power

Most every engine with a power complaint has the same routine, on a Cat you Change the fuel filters I like a FF211 Fleetguard and a 1212 primary Fleetguard. Check the fuel return line where it goes into the tank for flow.
Check the CAC. starting from the turbo outlet pressurizing the engine intake checking for valve guide blow-by, the boost gauge, and anyother leaks. Check the AFC, for leakage. Do a valve set, check for full throttle travel, and check the turbo turbine for damage to the outer ends of the wheel. That will cover 95% of them.
Black smoke is not power it is unburnt fuel.

 

Check the fuel line's. They collapse inside and you won't be able to tell from the outside. They collapse under a load and it would restrict the flow.

 

I use CAT 1R-0749 on my B model.

 

U will find the air fuel control valve is causeing the problem with the link in side the governor housing soon as it gets boost from the turbo it sets it self with the oil pressure from the engine then if u turn it off and start it agin it will be fine till it gets boost u have to dismantle the governor and check the link and the air fuel have had this problem before

 

That engine is notorious for three things. One being collapsed fuel lines as initially stated, second is two at once the air fuel ratio diaphragm rupturing and the AFR cover warping and leaking. You can check both by taking the cover bolts off and seeing if there is oil in the cover and you can also look at the cover gasket surface and see black soot where the boost gases have leaked. If there is oil in the cover the diaphragm inside needs replaced. Not a highl;y technical job but you must know what you arer doing when you re-install the AFR. Leave this function to a CAT person. The third is timing advance slipping or the carrier assembly coming apart. All have to be verified by taking timing cover off. If you taske the timing cover off and the weight carrier cover bolts off you can grasp the weight carrier and see if it slips if it does the assembly needs replaced. Leave this function to a CAT person because the weight assembly if not installed correctly can cause problems. The other rarity is if the Air tio Air Cooler ATAAC is leaking boost. The ATAAC needs pressure checked and you can visually look at clamping areas and look for black soot streaks. The clamps may be loose. They torque to a minimum of 90 in/lbs to 110 in/lbs. otherwise they leak or break.

 

I have 2 b models and run same for my primary.

 

Seems that all the most common things have been covered already. Sounds like afrc to me, diaphragm.