jjdiesel1990

Okay guys I have a 90 that has a denny t stage 2 fuel pin, 3800 rpm gov spring, star wheel bottomed, timing 1/8 bumped, smoke screw bottomed and full power screw in as far as it can go without running away. Stock turbo, rebuilt stock injectors (1 year ago), stock lift pump (6-7 yrs old). Rewind to last summer...truck would really blow smoke (not that i wanted to) and egts would soar past 1600 degrees. I was having trouble with the idle and full throttle travel (due to pump settings) and indexed the throttle shaft to fix this. About this time the head gasket started to leak and power started to decrease. I attributed the power loss to the head gasket and after a new gasket and mighty diesel's head bolts (inside of motor looked great!), the truck can barely blow any smoke and egts will not get over 1000 wot. This is with the pump set as high as it can go without runaway. I might add that during a few month time period I ran mixtures of wmo as high as 60%. Also, when truck was "powerful", it would occasionally seem to lose power or "cut out" at high rpm. Trucks idles and runs fine now (slight haze when cold), but is not close to where it was at power wise. Any ideas? When I had the head off I rotated the engine, and the lift pump seemed to be squirting fuel. Could the injectors be messed up from the oily fuel? Can throttle indexing effect power? Im at a loss. Sorry for the book lol. Any help is much appreciated.

93-12Smoke

Could be throttle indexing not giving you full travel. do you have a fuel pressure gauge?