I cant get the fuel pump assembly off the fuel tank and i see no lock ring. I have a 1994 Isuzu rodeo 2wd with a 3.2. anyone know what i can do?

check the tank is it plastic... if so drop the tank pour gas in bucket if black stuff in the gas take a water hose and spray it out wait till dry put it back on and put gas and try to start it,,, if fuel pump in tank replace it... please let me know how it turns out,,, good luck

Relieve the fuel pressure at the pump switch located in the passenger compartment under the carpet of the transmission hump on the passenger side. Remove the fuel tank. Turn the lock ring counterclockwise until it's loose and remove the lock ring. Pull the fuel pump/sending unit from the tank being careful not to bend the arm for the sending unit float. Discard the old lock ring seal. Installation is reverse of removal with the following additions: (a)Apply a coat of heavy grease to the new lock ring seal to hold it in place during assembly. Install the seal in the lock ring groove. (b)Install the fuel sender/pump unit into the fuel tank so that the tabs of the unit are positioned into the slots in the fuel tank. Make sure to keep the seal in place during installation until the lock ring has been tightened properly. (c)Hold the fuel sender/pump unit in place, install and tighten the locking ring clockwise until the stop is against the retainer ring tab. - Mazda Pickups Repair Manual

hope this help

Yes ,,instructions are below, Use eye protection for this procedure
Remove or Disconnect:

1. Relieve Fuel Pressure
2. Disconnect negative battery cable
3. Raise vehicle on hoist
4. Remove Fuel Tank
5. Remove Fuel Gage sending and pump assembly by turning cam lock ring counterclockwise. Lift assembly from fuel tank and remove fuel pump from fuel gage sender unit.
6. Disconnect pump wires, hose clamps, and clamp around pump body
7. Pull pump assembly out of rubber connectors
8. Inspect fuel pump attaching hose for any signs of deterioration. Replace as necessary.

Install or Connect:

1. Push fuel pump assembly into attaching hose
2. Connect pump wires, hose clamps at attaching hose and around pump body
3. Place Fuel tank sending unit and pump assembly into tank using new O-ring
4. Place cam lock over assembly and lock by turning clockwise
5. Install Fuel Tank
6. Start engine and check fuel pipe connector for visual leaks

Electric Fuel Pump REMOVAL & INSTALLATION Non-Supercharged

1. Disconnect the negative battery cable and properly relieve the fuel system pressure.
2. Remove the fuel tank and place it on a bench.
3. Remove any dirt that has accumulated around the fuel pump retaining flange so it will not enter the tank during pump removal and installation.
4. Turn the fuel pump locking ring counterclockwise and remove the locking ring.
5. Remove the fuel pump and bracket assembly. Remove and discard the seal ring. To install:
   
6. Clean the fuel pump mounting flange, fuel tank mounting surface and seal ring groove.
7. Apply a light coating of grease on a new seal ring to hold it in place during assembly and install in the seal ring groove.
8. Install the fuel pump and bracket assembly carefully to ensure the filter is not damaged. Make sure the locating keys are in the keyways and the seal ring remains in the groove.
9. Hold the pump assembly in place and install the locking ring finger-tight. Make sure all the locking tabs are under the tank lock ring tabs.
10. Rotate the locking ring clockwise until the ring is against the stops.
11. Install the fuel tank in the vehicle. Add a minimum of 10 gallons of fuel to the tank and check for leaks.
12. Install a suitable fuel pressure gauge on the valve on the fuel rail.
13. Turn the ignition switch from OFF to ON for 3 seconds. Repeat this procedure 5–10 times until the pressure gauge shows at least 35 psi. Check for fuel leaks.
14. Remove the pressure gauge, start the engine and check for leaks.

REMOVAL & INSTALLATION NOTE: To gain access to the fuel pump, it is necessary to remove the fuel tank.

1. Depressurize the fuel system and remove the fuel tank from the vehicle.
2. Remove any dirt that has accumulated around the fuel pump attaching flange, to prevent it from entering the tank during service.
3. Turn the fuel pump locking ring counterclockwise using a locking ring removal tool and remove the locking ring.
4. Remove the fuel pump and bracket assembly.
5. Remove the seal gasket and discard it. To install:
   
6. Put a light coating of heavy grease on a new seal ring to hold it in place during assembly. Install it in fuel tank ring groove. Fig. 1: Fuel pump and sending unit used on the Regular Cab Ranger pick-up
   Fig. 2: Fuel pump and sending unit used on the Super Cab Ranger pick-up
   Fig. 3: Fuel pump and sending unit used on the Explorer and Mountaineer
   
   
7. Insert the fuel pump assembly into the fuel tank, then secure it in place with the locking ring. Tighten the ring until secure.
8. Install the tank in the vehicle.
9. Install a minimum of 10 gallons of fuel and check for leaks.
10. Install a pressure gauge on the throttle body valve and turn the ignition ON for 3 seconds. Turn the key OFF, then repeat the key cycle five to ten times until the pressure gauge shows at least 30 psi. Reinspect for leaks at the fittings.
11. Remove the pressure gauge. Start the engine and check for fuel leaks.

In that year of vehicle I wouldn't be surprised if the fuel pump was in the tank. I would be surprised if it was not in the fuel tank.

fuel tank has to be removed to remove fuel pump sender unit. make sure tank is near empty so its not as heavy to remove
some models have two round rings on top of tank, one is sender unit (for gauge) the other incorporates the fuel pump
others have one round ring which is both in one
remove the one near middle section of tank
be carefull not to bend float arm for sender unit if twin type (sender & fuel pump in one)

I believe this is same truck as Ranger

Pump is in tank

Removal
NOTE: On some vehicles, fuel gauge sending unit is not available separately. On those vehicles, to replace sending unit, replace entire fuel pump .

1. Remove fuel tank as described in this section.

Removal and Installation
NOTE: Make sure fuel tank is properly supported during removal and installation procedures.

1. Drain fuel from fuel tank .

1. Loosen fill pipe clamp.

1. Remove bolts securing shield and bracket assembly to frame (5005) and remove assembly from vehicle.

1. Remove fuel tank filler pipe from vehicle.

1. Support fuel tank .

1. Remove bolts and nuts from rear fuel tank support strap and remove rear fuel tank support strap .

1. Remove bolt and nut from front fuel tank support strap and remove front fuel tank support strap .

1. Lower fuel tank .

1. Remove fuel feed hose at sender push connector.

1. Remove fuel return hose at sender unit push connector.

1. Disconnect sender and fuel pump electrical connector.

1. Remove fuel vapor hose from fuel vapor valve .

1. Lower fuel tank from vehicle

1. Remove fuel tank to bench. Remove any dirt that has accumulated around the fuel pump attaching flange so that it will not enter the fuel tank during fuel pump removal.

1. Turn the fuel tank sending unit locking retainer ring (9A307) counterclockwise with the Fuel Tank Lock Ring Wrench Tool T90T-9275-A or T86T-9275-A and remove fuel tank sending unit locking retainer ring .

1. Remove the fuel pump and sender assembly.

1. Remove fuel pump mounting gasket (9417) and discard.

1. If necessary, disconnect spade connector and remove two screws and fuel gauge sending unit.

Disconnect battery ground cable. Loosen fuel filler cap. Support underneath of the fuel tank protector Disconnect evaporative fuel hose at the canister. Disconnect fuel feed hose and fuel return hose near the fuel filter. Plug both ends of the fuel hoses to prevent fuel leakage. Disconnect air breather hose and fuel filler hose at the fuel filler neck. Cover fuel hose to prevent any dust entering. Remove the four fuel tank assembly fixing bolts at four corners of the tank. Let down the tank and disconnect the wiring connectors Remove fuel tank assembly along with protectors Remove retaining cover and roll over & float valve along with the evaporative fuel hose and pipe Remove fuel pump and sender assembly by removing the snap ring with the fuel hoses Remove protectors by removing the six fixing bolts

The fuel level sending unit is located inside the fuel tank along with the fuel pump and will need to be replaced if it has burned out. It may be included with a new fuel pump assembly or sold seperately. There could be a bad electrical connection so be sure and check that all electrical connections are clean and secured before you spend money replacing parts and removing the fuel tank.