To access it, you'll need to:
1. Safety First: Disconnect the negative battery terminal. Fuel is flammable, so work in a well-ventilated area, away from sparks or open flames.
2. Locate the Fuel Tank: It's usually under the rear passenger seat or in the bed of the truck (depending on the year and model). You'll need to access it from underneath the vehicle.
3. Drop the Fuel Tank (Usually Required): This is often the most challenging part. You'll need to disconnect the fuel lines (carefully!), the electrical connector to the fuel pump, and any tank straps or bolts securing it. Consult a repair manual specific to your Blazer's year and model for precise instructions – this varies considerably. Consider using a fuel tank strap wrench to avoid damage.
4. Remove the Fuel Pump Assembly: Once the tank is lowered or removed, you'll see the fuel pump assembly. The check valve is within this assembly. The assembly is typically held in place by a retaining ring or clips.
Important Considerations:
* Repair Manual: A repair manual specific to your S10 Blazer's year is *essential*. It will have diagrams showing the fuel system layout and step-by-step instructions for accessing and replacing the fuel pump assembly. Don't attempt this without one.
* Fuel Line Disconnect Tools: You'll need the correct tools to disconnect the fuel lines safely without causing leaks or damage.
* Fuel Pressure: There will be residual fuel pressure in the system. You may need a fuel pressure gauge and/or release valve to safely depressurize the system before disconnecting the fuel lines.
* Professional Help: If you're not comfortable working with fuel systems, it's best to have a qualified mechanic perform the repair. Improper handling of fuel can be dangerous.
It's extremely rare to replace just the check valve itself. The entire fuel pump module is usually replaced as a single unit when there's a problem with the check valve or other components within the assembly.
