How do i align the timing marks on crank,cam and injection pump in a isuzu 6he1 engine

I would invest in a Helms or Chilton manual first and foremost. Second, the proper way to align crank and cams is to take out the spark plug on cylinder #1, leave the timing belt off for the time being. With the spark plug out of the cylinder 1 spot, put a long screwdriver or metal rod that's small enough NICELY into the hole until it rests on the piston head, then take a ratchet and put it on the crank pulley bolt and rotate the crank until the rod goes all the way up, once it starts moving down, back it up until its top dead center(TDC). With cylinder 1 at TDC, look at the cam gear/s, they usually have markings or punches on them, usually by the teeth of the gear. Rotate those until they are at TDC as well(the markings). Once everything is at TDC, then you can re-install the timing belt and crank it up. I wouldn't recommend cranking the motor until you have it done correctly, otherwise you risk running into interference in the motor, which will inevitably bend valves and wreck piston heads.

Yet another empty post, we have 1000s with zero help.

no year
no country,
NO JOY.
all we know is its a 7.1Liter diesel engine.
what injection system is NOT KNOWN, due your lack of facts.
not even a truck stated,
the car has no body, the engine in a boat?
what, must we guess ALL THAT?
6HE1-TC diesel engine is introduced. 1994?
that engine.
try to learn, that telling what country, year and truck body its in
allows the helper to read the book for said engine. 10x more easy.
a win -win, thing. see?
not ever seen in my Rodeo. ever.