How do you change the fuel pump in a 1996 Blazer S-10?
The fuel pump is in the tank. This was the HARDEST repair job I've ever performed for a vehicle. I wouldn't do it again or help my best friend do such a repair. I wouldn't recommend it to anyone. Take it to a dealer for repair. The three fuel lines connected to the sending unit are nearly impossible to reconnect when trying to reinstall the tank. There's simply no room to work. Not to mention reconnecting the fuel filler and relief hoses. I had to cut the filler and relief hoses off ($75.00 total for both). I broke a plastic relief valve when trying to disconnect the hose attached to it ($25.00). And the three plastic hoses for fuel supply, return and relief cost $100.00 a piece. Luckily I didn't break any of these. But I came close. Don't try this unless you have plenty of time and paitences and can reinstall the fuel tank. It came out 5 times easier then it went back in.
First siphon the gas out. There are only two brackets that hold the fuel tank in place. Any substantial amount of fuel will make the tank fall once those brackets are removed and the tank is broke free of the mounting tape holding it in place. This could break the high-pressure hose connections and/or relief valve hose connections from the fuel tank. I had to raise the back of the vehicle considerabley to fit comfortably under it to work. Almost dangerously high. I wouldn't do this agian. 1. Remove the support bracket bolt located near the back of the tank and then the support bracket nut located near the front of the tank. The supporting brackets cradle the tank in two places and are band straps approximately two inches wide. With the bolt and nut removed, the two support bands can be pulled down individually and worked sideways and unclipped on the side opposite the bolt or nut. 2. With the support bands out of the way, the fuel tank can be worked side to side and pulled down to break it loose of the supporting tape holding it in place that was placed on the fuel tank during installation. BE CAREFUL that you don't pull the tank too far down towards the front, there is a relief valve and hose located on top of the tank that can easily break if the front of the tank is lowered too far down. The relief valve hose has a spring clamp holding the rubber hose in place. Remove the spring clamp with a small pair of channel locks or needle nose pliers and work the relief hose free. With the hose free, it will allow the front of the tank (closest to the engine) to be lowered to the ground for now. 3. The back of the tank has the main filler hose (2-1/2") and filler relief hose (1") and three smaller hoses which are the high pressure supply and return lines, plus the electrical connections. Remove the hose clamp from either side of the 2-1/2" hose and work the hose free from the tank. Do the same with the 1" hose. There is a set of quick release tools available at your local Autoparts store that are for removing the fuel lines etc... Should cost between $5.00 and $20.00. This can sometimes save you the cost of replacing the fuel lines if they break. I had to cut both of these hoses off because age hardened them and I couldn't get the hoses free. The replacement cost was $45 for the larger hose and $25 for the smaller hose from Chevrolet. With the two hoses removed, the back of the fuel tank can be lowered further so the high pressure lines can be disconnected, but first remove the electrical connections. There are two plugs that have a typical clip lock connection that needs to be released before each electrical plug can be worked free. 4. To remove the high-pressure supply and return lines, mark the three lines with different colored tape and note the placement of each before disconnecting the hoses. The two outside hoses (one supply and one return) have a white plastic clamp fitting that is removed by squeezing in on both side with needle nose pliers and pulling gently back on the hose connection. The middle hose is released by squeezing on the black outside hosing and gently pulling back on the hose. If you break the hoses, plan on spending hundreds to replace them. Each cost $100.00 from Chevy, the plastic hose clamps I found at NAPA. The fuel tank is now completely disconnected and can be removed. The fuel pump is held in place by a large snap ring-retaining clip. Once the clip is removed, the fuel pump will work free using a large sturdy screwdriver to gently pry upwards at different points around the fuel pump. Still have to clean out all the old debris in the tank... messy job. Then if you're lucky, you can reinstall the tank with the new fuel pump inside. Replacing the tank is not as hard as the above person makes it seem. It is difficult but almost anyone can do it if they take their time. I drove the vehicle up backwards on ramps to get it high enough to where I could sit under the back of the vehicle to loosen the fuel lines. As it it comes to the relief valve, I spoke to the chevy dealership parts person, and he said that they all brake when replacing the fuel tank. That was the only part that I needed to replace. Over all this wasn't too bad of a job to do on the vehicle.