Walbro 400lph Install on EK (1996-2000 Civic)
01-27-2012, 03:32 PM
#1
Honda-Tech Member
Thread Starter
Walbro 400lph Install on EK (1996-2000 Civic)
Well I started running out of fuel on high boost, so it was time for an upgrade. I went from the Walbro 255 to the new Walbro 400. I could not find any write ups on how to install this fuel pump into an EK and I had heard talks of having to do modifications due to the larger bottom end of the 400. I decided to tackle this project, take some pictures, and do a write up for those interested in running this pump. Wasn't quite sure what I was in for when I started, but it turned out to be pretty simple. So here it is for your viewing pleasure......
So, here is the monster. The big, bad Walbro 400lph. Let's see what it can do.
Just like any Civic fuel pump, you got to get to it under the rear seat cushion
The red and black wires you see coming out of the cover are upgraded 10 gauge wires for the fuel pump and inline relay. A must do upgrade when putting a lot of demand on the fuel pump. Take the four screws out to lift the cover and access the fuel pump and sending unit.
Unplug the fuel pump and take both fuel lines off.
Remove the 6 10mm nuts and pull out the fuel pump unit. Ah, there is the 255 that has served me well for the past four years.
Unclamp the hose on top of the old pump and remove the pump from the bracket. Should be a tight fit, but it will come out. *Caution* Remove the plug for the power and ground BEFORE removing the pump from the bracket. If it is still plugged in, you run the risk of tearing the wires and connector right off and with have to do some wire repairs. I didn't do it on this one, but I have done it before.
Here you can see some of the differences in of the 255 vs. the 400. Physically the bottom is bigger on the 400 then the 255. I think this is where the rumors are coming from that a bit of modification has to be done to get it to fit. As you will see later, this is not the case.
Here are the differences to the top of the pumps. As you can see, unlike the 255, the 400 is not a "plug and play." Not only will the stock connector not plug in, but the power and ground terminals are on the opposite sides of the pump on the 400 as opposed to the 255.
There are instal kits out there that you can get for this pump. I am not sure if will allow you to plug in the stock connector or not. I opted to not get the instal kit and just figure it out. Pretty simple though, just de-pin the 2 wires from the stock fuel pump connector. The pins will actually plug right onto the 400, but again the terminals are on opposite sides.
Wires connected to the 400.
The ground wire is screwed onto the pump assembly bracket on the right side of the pump. The plug connector on the top (outside) of the fuel pump assembly has power and ground pins. The power wire continues all the way down to the pump, but the ground pin goes strait to the pump assembly/bracket.
Top side of pump assembly (shitty pic)
Underside of pump assembly/bracket where the power wire comes through down to the pump.
Not sure how they did it, but the screw stripped out on me when I tried to take it off. So I cut it off.
I decided why not beef up the ground strap. Couldn't hurt, so I used 10 gauge on that as well. There are 2 little holes on the fuel pump bracket just left of the fuel pump. I used a self tapping screw and secured the new ground strap to the bracket on the left side of the pump.
Pic of self tapping screw and ground strap.
Power side of wiring now on the left side of pump.
Wiring complete
Once the wiring was finished, it was time to move on to the next part that needed to be modified. The rubber grommet at the bottom of the fuel pump holds the pump into the fuel pump assembly/bracket along with the hose and hose clamp at the top of the pump. Because the bottom of the 400 is significantly larger than the 255 (and because a new rubber grommet was not provided), I modified the stock grommet to make it fit onto the 400 while still being able to fit into the bracket and hold the pump.
Stock rubber grommet on the 400.
In the bracket
As you can see, the grommet will go back into the bracket just fine, but does not sit on the bottom of the 400 squarely. Now you can just shove it back in and I am sure it may hold, but I decided to get it to fit a little better. All it took was a Dremel and a pair of ****s.
Top side of stock grommet. Notches in the rubber that held the 255 in place.
Used the Dremel to elongate those notches to better fit the bottom of the 400. Again, shitty pic I know.
I wasn't sure what these ports were on the bottom side of the 400, but when I blew into the inlet side of the pump, air would come out of these ports. I thought it might be important, so I cut a piece out of the grommet to accommodate for the ports.
Ports on the bottom left side (I know, I know)
Grommet notched for ports.
A little extra cut here and a little finesse there, and your in business.
As you can see, once the 400 is in place on the bracket, there is no clearance issues with the bottom of the pump being larger.
Just put the outlet side on the hose, and push the pump downward into the grommet and base of the bracket, tighten the hose clamp, and BAM! Done like dinner.
Couple of extras: I figured I would replace the fuel pump sock while I was in there. The one I took out was at least 13 years old. It looked like it was about time. Thanks Checker's (sorry, O'Reilly's).
This is the seal or rubber gasket for the fuel pump assembly. I must not have payed much attention to it when I installed the 255. Be careful when installing the fuel pump assembly not to get this gasket folded or caught on the studs that hold down the assembly.
It never leaked on me, but I figured why not get a new one.
Ready to go back in. Never to be seen again.
Good buy Walbro 400lph. Make us proud!
Install is the opposite of removal. Just be careful and take your time. Make sure the sock is positioned correctly in the tank and you do not fold up the gasket. Leave the cover off and turn the key on to position #2 to check for correct wiring. You should hear the pump prime up. Do that a couple of times to prime up the fuel system. Start the car and check for any leaks. Once you are content with your work, put the cover and seat cushion back on.
Now I have read that the sock and the position of the Walbro 400 makes the reading on your fuel gauge wrong. Supposedly you will run out of fuel when your gauge still reads a half of a 1/4 tank. I don't know if this is true or even possible. The pump, sock, whole assembly sits in the exact same position as before. There should not be any fuel gauge issues that come about from this instal. Anyways, with any vehicle running boost, you should never let your fuel tank get anywhere close to being on the empty side.
As with any instal or modifications, please be safe. I am not taking any responsibility for anyone attempting this project. Don't smoke or have open flames around the fuel system. Keep the drop lights far away from the fuel tank once it is open. And if your going to drink, well I've said my peace.
Hope this helps people out there. I know I had a few of my questions answered and a few myths busted while attempting this install.
Now it's off to a dyne session I go............
So, here is the monster. The big, bad Walbro 400lph. Let's see what it can do.
Just like any Civic fuel pump, you got to get to it under the rear seat cushion
The red and black wires you see coming out of the cover are upgraded 10 gauge wires for the fuel pump and inline relay. A must do upgrade when putting a lot of demand on the fuel pump. Take the four screws out to lift the cover and access the fuel pump and sending unit.
Unplug the fuel pump and take both fuel lines off.
Remove the 6 10mm nuts and pull out the fuel pump unit. Ah, there is the 255 that has served me well for the past four years.
Unclamp the hose on top of the old pump and remove the pump from the bracket. Should be a tight fit, but it will come out. *Caution* Remove the plug for the power and ground BEFORE removing the pump from the bracket. If it is still plugged in, you run the risk of tearing the wires and connector right off and with have to do some wire repairs. I didn't do it on this one, but I have done it before.
Here you can see some of the differences in of the 255 vs. the 400. Physically the bottom is bigger on the 400 then the 255. I think this is where the rumors are coming from that a bit of modification has to be done to get it to fit. As you will see later, this is not the case.
Here are the differences to the top of the pumps. As you can see, unlike the 255, the 400 is not a "plug and play." Not only will the stock connector not plug in, but the power and ground terminals are on the opposite sides of the pump on the 400 as opposed to the 255.
There are instal kits out there that you can get for this pump. I am not sure if will allow you to plug in the stock connector or not. I opted to not get the instal kit and just figure it out. Pretty simple though, just de-pin the 2 wires from the stock fuel pump connector. The pins will actually plug right onto the 400, but again the terminals are on opposite sides.
Wires connected to the 400.
The ground wire is screwed onto the pump assembly bracket on the right side of the pump. The plug connector on the top (outside) of the fuel pump assembly has power and ground pins. The power wire continues all the way down to the pump, but the ground pin goes strait to the pump assembly/bracket.
Top side of pump assembly (shitty pic)
Underside of pump assembly/bracket where the power wire comes through down to the pump.
Not sure how they did it, but the screw stripped out on me when I tried to take it off. So I cut it off.
I decided why not beef up the ground strap. Couldn't hurt, so I used 10 gauge on that as well. There are 2 little holes on the fuel pump bracket just left of the fuel pump. I used a self tapping screw and secured the new ground strap to the bracket on the left side of the pump.
Pic of self tapping screw and ground strap.
Power side of wiring now on the left side of pump.
Wiring complete
Once the wiring was finished, it was time to move on to the next part that needed to be modified. The rubber grommet at the bottom of the fuel pump holds the pump into the fuel pump assembly/bracket along with the hose and hose clamp at the top of the pump. Because the bottom of the 400 is significantly larger than the 255 (and because a new rubber grommet was not provided), I modified the stock grommet to make it fit onto the 400 while still being able to fit into the bracket and hold the pump.
Stock rubber grommet on the 400.
In the bracket
As you can see, the grommet will go back into the bracket just fine, but does not sit on the bottom of the 400 squarely. Now you can just shove it back in and I am sure it may hold, but I decided to get it to fit a little better. All it took was a Dremel and a pair of ****s.
Top side of stock grommet. Notches in the rubber that held the 255 in place.
Used the Dremel to elongate those notches to better fit the bottom of the 400. Again, shitty pic I know.
I wasn't sure what these ports were on the bottom side of the 400, but when I blew into the inlet side of the pump, air would come out of these ports. I thought it might be important, so I cut a piece out of the grommet to accommodate for the ports.
Ports on the bottom left side (I know, I know)
Grommet notched for ports.
A little extra cut here and a little finesse there, and your in business.
As you can see, once the 400 is in place on the bracket, there is no clearance issues with the bottom of the pump being larger.
Just put the outlet side on the hose, and push the pump downward into the grommet and base of the bracket, tighten the hose clamp, and BAM! Done like dinner.
Couple of extras: I figured I would replace the fuel pump sock while I was in there. The one I took out was at least 13 years old. It looked like it was about time. Thanks Checker's (sorry, O'Reilly's).
This is the seal or rubber gasket for the fuel pump assembly. I must not have payed much attention to it when I installed the 255. Be careful when installing the fuel pump assembly not to get this gasket folded or caught on the studs that hold down the assembly.
It never leaked on me, but I figured why not get a new one.
Ready to go back in. Never to be seen again.
Good buy Walbro 400lph. Make us proud!
Install is the opposite of removal. Just be careful and take your time. Make sure the sock is positioned correctly in the tank and you do not fold up the gasket. Leave the cover off and turn the key on to position #2 to check for correct wiring. You should hear the pump prime up. Do that a couple of times to prime up the fuel system. Start the car and check for any leaks. Once you are content with your work, put the cover and seat cushion back on.
Now I have read that the sock and the position of the Walbro 400 makes the reading on your fuel gauge wrong. Supposedly you will run out of fuel when your gauge still reads a half of a 1/4 tank. I don't know if this is true or even possible. The pump, sock, whole assembly sits in the exact same position as before. There should not be any fuel gauge issues that come about from this instal. Anyways, with any vehicle running boost, you should never let your fuel tank get anywhere close to being on the empty side.
As with any instal or modifications, please be safe. I am not taking any responsibility for anyone attempting this project. Don't smoke or have open flames around the fuel system. Keep the drop lights far away from the fuel tank once it is open. And if your going to drink, well I've said my peace.
Hope this helps people out there. I know I had a few of my questions answered and a few myths busted while attempting this install.
Now it's off to a dyne session I go............
01-27-2012, 04:57 PM
#6
Honda-Tech Member
Thread Starter
Re: Walbro 400lph Install on EK (1996-2000 Civic)
That sucks! I put a lot of time into putting that together. The pics show up for me when I open up the thread. All other pics that I have ever posted have come up. I may have to rewrite it and figure out another way to post pics. Sorry guys.
01-27-2012, 05:31 PM
#7
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Re: Walbro 400lph Install on EK (1996-2000 Civic)
You need to host the photos somewhere other than your computer for anyone to see them.....
Try using photobucket
Try using photobucket
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01-27-2012, 09:01 PM
#9
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Thread Starter
Re: Walbro 400lph Install on EK (1996-2000 Civic)
Alright, I tried it with Photobucket. It's under the same title with V.1.2 added to the end. Hope it works out this time.
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