Tahoe - Fuel Pump Replacement
Time: 2-4 hours
Fuel Pump for Z engine:
ACDelco MU2294
Delphi FG0810 (I used this one)
Tank Ring: ACDelco TR19
Connectors to pump 3/8 and 5/16 fuel line connection nylon strength?
I thought I would do a write up on how to replace the tank on my 2004 Chevy Tahoe Z71. I am sure there are other write ups but I wanted this for myself if I ever have to do this job again. It took me about 4 hours to do this job, with one run to the parts store to get the lock ring (I had bought the wong one). I forgot to take pictures so if anyone does this and take some pics, send them to me and I will post.
First off, working with gasoline, don't spill it and if you do, try to soak it up and put the rags as far away from you and the truck as possible. Gasoline evaporates and will stay low to the ground. If anything sparks it, you will get one massive fireball with you and your truck in the middle of it all. Not a good way to start the day. Move fuel containers, rags etc far away from the work area. If you spill fuel, take a break and let it evaporate.
What you will need, in order:
LED light (avoid a tungsten light since if you break the bulb while it is on and you have fuel vapors... it could be really bad)
PB Blaster or similar.
Floor jack. I would avoid a bottle jack as it is too high.
Jack stands x2 or ramps.
1" (verify) and 1.5" cap and clamps. This is for filler holes at back of tank. Pick up at Hardware store in plumbing isle.
13 and 15mm sockets, extensions, ratchet, screwdrivers.
Fuel pump. Make sure you get the specific model for your vehicle. There are different ones for the flex (ethanol or Z) engines. Using the wrong one, if you were to fill up with E85 would most likely ruin the pump.
Lock ring. Since the tank has a recess at the pump, (not a brilliant design), when water gets up there, it must sit. Rings rust out pretty good. Mine was salvageable, but it would have needed a coat of paint and i did not feel like doing that.
Old Screwdriver or metal rod or chisel, and a hammer to remove lockring. There is an SST for this job. If you have access to it, I would highly recommend getting it.
Compressed air. To clean off parts and tank. If you don't have, rags will do.
Empty fuel container and funnel. You can pickup an oil drain pan that has a large funnel at the top with plug at bottom of funnel. When fuel falls into the top of this drain pan, it will fall into the container. This is nice as vapors will be contained as much as possible inside the drain pan.
Day before. I sprayed down all the bolts i was to remove with PB Blaster. I checked to see if they could be loosened up and they broke free. Spraid a little more. If you are going to replace fuel filter, spray the rear nut of filter down as well, and let that one soak.
I have seen some videos where people remove the rear drive shaft. In restrospect, I wish i had done this as it was a PITA to get around. Plus mine is pretty rusted and could use a coat of paint.
Step 1. Get fuel tank as empty as possible. I had about 75 miles left on the range indicator on gauge cluster. (my fuel leve gauge stepper motor is dead). It was probably about 4-5 gallons. This was manageable and I could lift it on my own. Ideally you have less. Since the tank is filled at the rear, and you will drop the rear of the tank, too much fuel in tank can cause nasty spill. You cannot syphon the tank from the filler neck since there are screens at the tank that prevent you from getting a hose into the tank.
Step 2. Jack rear of truck and put it on jackstands or get it up on ramps. Choke wheels at front (both sides). The higher the truck is, the more comfortable the rest of your journey will be.
Step 3. Get a fuel proof container ready in case of fuel spills. Disconnect the fuel filler hoses. There are two (large and small overflow). I guess you could do either the upper, or lower area. I chose to do lower. Lower may be easier since you can tug on hose more due to tank being secured. You will see the metal screens. At this point, if your tank is full (ie one of those guys who's luck ran out and happened to fill their tank just before the fuel pump crapped out), you will want to siphon it out. I did not do this, put screens should pop out and you can get to fuel. Be VERY careful again when dealing with fuel and do your research as to does and don't. Use the caps to cap the two openings at rear of tank and tighten them.
I have seen some videos where people recommended duct tape. I did this for smaller fitting. But it leaked out a bit here, plus tape got all gooey and made a mess. Caps will work better. Realize that fuel will increase the pressure on the these caps and/or duct tape as you lower the tank more. You really want to avoid major leakage.
Step . Put jack under rear of tank. I put a small board to prevent damaging tank. Put a little pressure to hold it in place, but don't go crazy.
Step . Unbolt the evaporation canister (not sure if this is the exact name). Two bolts, 13mm i think. I could not get this puppy out, but at least I could have a little more wiggle room.
NOTE (Read before continuing): My tank had 6 connections. 2 hoses and two electrical fittings at the pump. One hose at rear and one at front for evap canister. From what I remember, the critical ones are the fuel pump connections; if you lower tank too much, it will strain these making it difficult to remove under tension, or worse, you may damage the hose or fittings. The front and rear evap cannister fittings had much more play in them, especially after loosening the canister. I would imagine you could lower entire tank without removing them.
Step . Begin to remove front and rear bolts and straps. Make sure jack is holding up the tank before completely removing the straps otherwise it will come down hard and probably cause damage. These take a 15mm socket. There is one bolt for each strap. The strap hook into frame on passenger side. These bolts go into a captured nut that camps onto the bracket (not a welded capture nut) so it may move back and forth a little).
Step . Now, you are going to want to lower it enough, to get the 4 fuel pump connections off (2 hoses and 2 elec connections). Lower tank a little bit, VERY slowly until you can get to the fuel pump. The fuel hose clips, you need to squeese both sides until they disengage, then pull the hose off. BE CAREFUL since most fuel pumps do not come with the part you squeeze and need to reinstall. (Why i have no idea since it probably is a 5c part). I had a hard time removing these and some people have recommended needlenose pliers to squeese the clamps.
Step . Pull fuel pump hoses out of clamps on fuel tank. There are two press in connection on the tank as you go from pump to the front of the truck. Mine had some kind of top piece that held the hoses in more securily toward rear of thank, but not at front. Not sure why. That piece pops off and is held by small piece of plastic at front of the clamp.
In next steps, this will depend on how high you raised your truck. You may want to provide a jack for front of tank or some blocks of wood, to prevent tank from falling out.
Step . Once all fuel pump connections are loose, then you can continue lowering tank very slowly while checking that nothing is binding. If you can, remove front and rear Evap connections. Again, this is a squeese connection and will come off much easier than the fuel pump fittings due to being a low pressure system.
As fuel shifts to rear of tank, it will get heavier at the rear of tank. Put jack under rear of tank. Front of tank will be held in place on metal crossbar. You may want to use the second jack, or something to help the front of the tank down slowly. You can pull the tank toward rear of truck and it should come off the cross bar.
Now move the tank out from under the truck so you can work comfortably. I have seen videos of people replacing the fuel pump under the truck with tank still sitting on front crossbar. This may be ok if you have the SST. But pulling fuel pump out will most likely make a mess with fuel going everywhere.
First thing, plug up all hose openings with some tape. Then clean the top of the tank really good to avoid getting crap into the tank when you remove pump. Remove lock ring. This was a real PITA on my tank as it was pretty rusty. I would recommend some PB Blaster on the ring and let it soak.
There was a plastic lock that you move away from center of pump, while reversing the ring. Again, be careful not to create sparks if there are fumes around (hence capping the hose fittings). You can use a brass drift to avoid sparks but it would have been too soft for how much i had to hammer on the damn thing. A steel rod did the best since the screwdriver tended to cut into the ring.
If you are going to reuse your ring and it is rusty, I would recommend painting it before you reinstall.
Once ring removed, Clean the top of tank one last time (blast of air). Get your funnel ready since you will spill fuel. Pull fuel pump out. You will need to tilt it slightly to get float out. The inside of pump is full of fuel, so dump it out into your funnel and container.
Remove the plastic hose clips off old pump and install on new pump. Put new gasket on new pump (pump should come with it, though my old one seemed in perfect shape). Clip on sender float. Drop it in the tank. Hose fittings go toward front of tank and there is a small metal clip that will position itself in tank. Make sure that is in place before installing lock ring. Tighten ring until it clips into the plastic lock spring (have no idea why the hell you would need this since you probably would have to drive your truck off a cliff before this damn lock ring would ever come loose). It took almost as much effort and hammer blows to get new ring on (a crap load). Again, had i known, I would have bought the SST. A ratchet fits into the SST, that has 3 fingers to lock into the ring making this job easy.
Now you are ready to reinstall.
Get tank back under truck. Lift front of tank onto crossbar. At this point, you will want to clip all hose fittings (especially the fuel pump hoses) back in. I did so after clipping them into the new pump and it was a PITA to do with little to now clearance, once tank was almost in position. Raise tank up so that you can connect fuel pump hoses and electrical connection (4 connections). Connect front and rear evap hoses. Now raise tank back up, put straps back on, and tighten.
I used a little anti-seize on all bolt prior to putting back in to assure an easy removal in the future (god forbid).
If needed, add fuel. You can prime the pump by turning key to run positions, waiting a few seconds, turning back off. Do this a few times. I forgot so it did not start on first try.
Time: 2-4 hours
Fuel Pump for Z engine:
ACDelco MU2294
Delphi FG0810 (I used this one)
Tank Ring: ACDelco TR19
Connectors to pump 3/8 and 5/16 fuel line connection nylon strength?
I thought I would do a write up on how to replace the tank on my 2004 Chevy Tahoe Z71. I am sure there are other write ups but I wanted this for myself if I ever have to do this job again. It took me about 4 hours to do this job, with one run to the parts store to get the lock ring (I had bought the wong one). I forgot to take pictures so if anyone does this and take some pics, send them to me and I will post.
First off, working with gasoline, don't spill it and if you do, try to soak it up and put the rags as far away from you and the truck as possible. Gasoline evaporates and will stay low to the ground. If anything sparks it, you will get one massive fireball with you and your truck in the middle of it all. Not a good way to start the day. Move fuel containers, rags etc far away from the work area. If you spill fuel, take a break and let it evaporate.
What you will need, in order:
LED light (avoid a tungsten light since if you break the bulb while it is on and you have fuel vapors... it could be really bad)
PB Blaster or similar.
Floor jack. I would avoid a bottle jack as it is too high.
Jack stands x2 or ramps.
1" (verify) and 1.5" cap and clamps. This is for filler holes at back of tank. Pick up at Hardware store in plumbing isle.
13 and 15mm sockets, extensions, ratchet, screwdrivers.
Fuel pump. Make sure you get the specific model for your vehicle. There are different ones for the flex (ethanol or Z) engines. Using the wrong one, if you were to fill up with E85 would most likely ruin the pump.
Lock ring. Since the tank has a recess at the pump, (not a brilliant design), when water gets up there, it must sit. Rings rust out pretty good. Mine was salvageable, but it would have needed a coat of paint and i did not feel like doing that.
Old Screwdriver or metal rod or chisel, and a hammer to remove lockring. There is an SST for this job. If you have access to it, I would highly recommend getting it.
Compressed air. To clean off parts and tank. If you don't have, rags will do.
Empty fuel container and funnel. You can pickup an oil drain pan that has a large funnel at the top with plug at bottom of funnel. When fuel falls into the top of this drain pan, it will fall into the container. This is nice as vapors will be contained as much as possible inside the drain pan.
Day before. I sprayed down all the bolts i was to remove with PB Blaster. I checked to see if they could be loosened up and they broke free. Spraid a little more. If you are going to replace fuel filter, spray the rear nut of filter down as well, and let that one soak.
I have seen some videos where people remove the rear drive shaft. In restrospect, I wish i had done this as it was a PITA to get around. Plus mine is pretty rusted and could use a coat of paint.
Step 1. Get fuel tank as empty as possible. I had about 75 miles left on the range indicator on gauge cluster. (my fuel leve gauge stepper motor is dead). It was probably about 4-5 gallons. This was manageable and I could lift it on my own. Ideally you have less. Since the tank is filled at the rear, and you will drop the rear of the tank, too much fuel in tank can cause nasty spill. You cannot syphon the tank from the filler neck since there are screens at the tank that prevent you from getting a hose into the tank.
Step 2. Jack rear of truck and put it on jackstands or get it up on ramps. Choke wheels at front (both sides). The higher the truck is, the more comfortable the rest of your journey will be.
Step 3. Get a fuel proof container ready in case of fuel spills. Disconnect the fuel filler hoses. There are two (large and small overflow). I guess you could do either the upper, or lower area. I chose to do lower. Lower may be easier since you can tug on hose more due to tank being secured. You will see the metal screens. At this point, if your tank is full (ie one of those guys who's luck ran out and happened to fill their tank just before the fuel pump crapped out), you will want to siphon it out. I did not do this, put screens should pop out and you can get to fuel. Be VERY careful again when dealing with fuel and do your research as to does and don't. Use the caps to cap the two openings at rear of tank and tighten them.
I have seen some videos where people recommended duct tape. I did this for smaller fitting. But it leaked out a bit here, plus tape got all gooey and made a mess. Caps will work better. Realize that fuel will increase the pressure on the these caps and/or duct tape as you lower the tank more. You really want to avoid major leakage.
Step . Put jack under rear of tank. I put a small board to prevent damaging tank. Put a little pressure to hold it in place, but don't go crazy.
Step . Unbolt the evaporation canister (not sure if this is the exact name). Two bolts, 13mm i think. I could not get this puppy out, but at least I could have a little more wiggle room.
NOTE (Read before continuing): My tank had 6 connections. 2 hoses and two electrical fittings at the pump. One hose at rear and one at front for evap canister. From what I remember, the critical ones are the fuel pump connections; if you lower tank too much, it will strain these making it difficult to remove under tension, or worse, you may damage the hose or fittings. The front and rear evap cannister fittings had much more play in them, especially after loosening the canister. I would imagine you could lower entire tank without removing them.
Step . Begin to remove front and rear bolts and straps. Make sure jack is holding up the tank before completely removing the straps otherwise it will come down hard and probably cause damage. These take a 15mm socket. There is one bolt for each strap. The strap hook into frame on passenger side. These bolts go into a captured nut that camps onto the bracket (not a welded capture nut) so it may move back and forth a little).
Step . Now, you are going to want to lower it enough, to get the 4 fuel pump connections off (2 hoses and 2 elec connections). Lower tank a little bit, VERY slowly until you can get to the fuel pump. The fuel hose clips, you need to squeese both sides until they disengage, then pull the hose off. BE CAREFUL since most fuel pumps do not come with the part you squeeze and need to reinstall. (Why i have no idea since it probably is a 5c part). I had a hard time removing these and some people have recommended needlenose pliers to squeese the clamps.
Step . Pull fuel pump hoses out of clamps on fuel tank. There are two press in connection on the tank as you go from pump to the front of the truck. Mine had some kind of top piece that held the hoses in more securily toward rear of thank, but not at front. Not sure why. That piece pops off and is held by small piece of plastic at front of the clamp.
In next steps, this will depend on how high you raised your truck. You may want to provide a jack for front of tank or some blocks of wood, to prevent tank from falling out.
Step . Once all fuel pump connections are loose, then you can continue lowering tank very slowly while checking that nothing is binding. If you can, remove front and rear Evap connections. Again, this is a squeese connection and will come off much easier than the fuel pump fittings due to being a low pressure system.
As fuel shifts to rear of tank, it will get heavier at the rear of tank. Put jack under rear of tank. Front of tank will be held in place on metal crossbar. You may want to use the second jack, or something to help the front of the tank down slowly. You can pull the tank toward rear of truck and it should come off the cross bar.
Now move the tank out from under the truck so you can work comfortably. I have seen videos of people replacing the fuel pump under the truck with tank still sitting on front crossbar. This may be ok if you have the SST. But pulling fuel pump out will most likely make a mess with fuel going everywhere.
First thing, plug up all hose openings with some tape. Then clean the top of the tank really good to avoid getting crap into the tank when you remove pump. Remove lock ring. This was a real PITA on my tank as it was pretty rusty. I would recommend some PB Blaster on the ring and let it soak.
There was a plastic lock that you move away from center of pump, while reversing the ring. Again, be careful not to create sparks if there are fumes around (hence capping the hose fittings). You can use a brass drift to avoid sparks but it would have been too soft for how much i had to hammer on the damn thing. A steel rod did the best since the screwdriver tended to cut into the ring.
If you are going to reuse your ring and it is rusty, I would recommend painting it before you reinstall.
Once ring removed, Clean the top of tank one last time (blast of air). Get your funnel ready since you will spill fuel. Pull fuel pump out. You will need to tilt it slightly to get float out. The inside of pump is full of fuel, so dump it out into your funnel and container.
Remove the plastic hose clips off old pump and install on new pump. Put new gasket on new pump (pump should come with it, though my old one seemed in perfect shape). Clip on sender float. Drop it in the tank. Hose fittings go toward front of tank and there is a small metal clip that will position itself in tank. Make sure that is in place before installing lock ring. Tighten ring until it clips into the plastic lock spring (have no idea why the hell you would need this since you probably would have to drive your truck off a cliff before this damn lock ring would ever come loose). It took almost as much effort and hammer blows to get new ring on (a crap load). Again, had i known, I would have bought the SST. A ratchet fits into the SST, that has 3 fingers to lock into the ring making this job easy.
Now you are ready to reinstall.
Get tank back under truck. Lift front of tank onto crossbar. At this point, you will want to clip all hose fittings (especially the fuel pump hoses) back in. I did so after clipping them into the new pump and it was a PITA to do with little to now clearance, once tank was almost in position. Raise tank up so that you can connect fuel pump hoses and electrical connection (4 connections). Connect front and rear evap hoses. Now raise tank back up, put straps back on, and tighten.
I used a little anti-seize on all bolt prior to putting back in to assure an easy removal in the future (god forbid).
If needed, add fuel. You can prime the pump by turning key to run positions, waiting a few seconds, turning back off. Do this a few times. I forgot so it did not start on first try.
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