randy803
New member
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- Location
- South Carolina
My recently purchased 1987 M998 with the 6.2 NA (Troop Carrier model) motor simply had no get up and go. It was so bad that you could not start on a steep hill, it simply would not go. When Offroad it was useless as it had no power from idle.
I checked the injection pump timing visually and noticed it was RETARDED. (judging by the scribed lines position to each other) I also noticed I never blew any smoke out the exhaust not even under a max load.
I set the injection pump timing, advancing it one line width from center alignment (about 1 degree) it was about 2degrees retarded so figure I advanced about 3 degrees total.
I then increased the IP fuel by about 1/8 turn.
All I can tell you is this is a different Humvee now. It has a lot more torque from idle, can start on hills and accelerates much stronger.
This truck spent it's life at Fort Bragg NC as a base truck, I am guessing it was de-tuned for this reason? No idea but I am glad it is better now.
I checked the injection pump timing visually and noticed it was RETARDED. (judging by the scribed lines position to each other) I also noticed I never blew any smoke out the exhaust not even under a max load.
I set the injection pump timing, advancing it one line width from center alignment (about 1 degree) it was about 2degrees retarded so figure I advanced about 3 degrees total.
I then increased the IP fuel by about 1/8 turn.
All I can tell you is this is a different Humvee now. It has a lot more torque from idle, can start on hills and accelerates much stronger.
This truck spent it's life at Fort Bragg NC as a base truck, I am guessing it was de-tuned for this reason? No idea but I am glad it is better now.
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