Walbro Fuel Pump

Czarnecki · 08-17-2006, 03:44 PM

I just installed my Walbro fuel pump to prepare for my DB 20G. Below are pictures to guide anyone through this process. I thought this was a pretty easy install, but I did encounter a few minor problems which were easily fixed. I am by far not a master mechanic, so if someone thinks I did something wrong, your comments are appreciated.

TRM 20-AUG-2006: added to the How-To catalog sticky

Czarnecki · 08-17-2006, 03:54 PM

The first step is to remove the rear seat, two bars, and black trunk cover. I believe 13 12mm bolts and four plastic pushins.

This is what it should look like. On the passenger side, there is a 4 screw cover just before entering the trunk. Remove this to access the pump and sending unit.

Now the next VERY IMPORTANT step is to unplug the white electrical connection. Once unplugged, the car needs to be started in order to relieve the pressure in the fuel lines. You will notice that the CEL and Low Fuel will light up and the car will start running bad. Eventually it will die, but I reccomend trying to restart it to ensure the pressure is out of the line. (I didnt restart and had a little gas spill in the garage) After doing this, its a good idea to unplug the negative terminal on the battery to avoid a fire because you will smell a lot of gas, expecially if you are like me and do this on a full tank

.

Czarnecki · 08-17-2006, 04:08 PM

Now the three lines need to be disconnected. I used pliers to move the clamp on the two smaller lines. The third line that faces the front of the car is the high pressure line, so be carefull. I recommend placing a pan underneath the gas tank and having a large rag ready because I had a fair amount of gas come out. This connection can be taken off by hand.

Remove the 8 small bolts holding the cover on. Be careful not to drop them. Now here comes the tricky part. You will need to remove a very large sending unit through a fairly small hole in the floor. Here is where you will be on your own, but it can be done. Be careful not to bend the sending unit float (a little is ok- but dont get mad at me if you damage anything). Try pivoting the unit 180 degrees like the pictures below show.

Czarnecki · 08-17-2006, 04:15 PM

Here is a picture of the sending unit on the workbench. I would put it in a clean pan. (I know my pan wasnt too clean)

Here are pictures of the Walbro kit:

In the last picture, you can see what the new pump will replace.

Now the old pump needs to be removed from the sending unit. I removed the two screws that holds the bottom fuel filter chamber on.

Now, disconnect the black hose from the diaphram thing to the fuelpump with pliers. Also disconnect the wires to the pump. The pump should come out with the original fuel filter attached.

Czarnecki · 08-17-2006, 04:31 PM

Now, the new fuel filter needs to be attached to the new Walbro pump. The kit will come with a tiny lock washer or snap ring. Be careful not to loose it. Place the filter on the pump and press the snap ring on the center part of the pump with a small socket.

Make sure the snapring is all the way on.

When reinstalling the new pump, I ran into a small problem. When I used the new rubber piece or pump isolator on the bottom of the pump where the fuel filter goes, I noticed that the extension comming form the pump overlapps the extension comming from the diaphram thing above it. I was unsure how to get a piece of new rubber hose to connect the two. Below are pictures of my problem.

I realized that if I pushed them together, I could get them to line up.

My solution to this problem was to cut the new rubber hose so that if you push it all the way on the diaphram extension, you would just see the end. Look below to see what I am talking about.

After cutting the hose in the way I described, I proceded to push the two parts together like I did before when the hose wasnt on.

Finally, I slid the hose over the two extensions so both had good coverage, and I tightened the hose clamps.

Czarnecki · 08-17-2006, 04:37 PM

The rest of this install is easy. Just remember to use the new wire provided to connect the new pump.

Put everything back together except for the fuel filter chamber bottom section. I needed to slightly modify this to accomidate the new fuel filter. I needed to cut some of the plastic out including the rubber around the top of the plastic fuel filter tube, and the back two plastic tabs. Just dont cut more than you need to.

Czarnecki · 08-17-2006, 04:40 PM

For the rest of the process, just put everything back the way it was. Just be careful not to bend the sending unit arm on the way into the tank.

Now you are ready for a big turbo and some injectors.

JJ18Sniper · 08-20-2006, 01:20 PM

Very detailed thread, great work! I had mine installed by Tony@xxtuning in 15 minutes flat, but if I didn't have the opportunity this would have helped.

**TRM** · 08-20-2006, 02:39 PM

nice work man. i added your How-To to the Sticky!

be prepared to have questions though. pics are great but you might need to give a bit of text with some of them.

thanks for sharing with us!

Doctor Subie · 08-22-2006, 09:49 PM

Great step by step write up, making it easy even for us mechanically challenged to do! One thing: I read on a previous Walbro install to re-use the stock filter, as it does a better job of filtering on our STI's, and to use the Walbro supplied filter if you have a WRX...link here:
http://www.iwsti.com/forums/showthread.php?t=34720

Any comments on that?

esstidefi · 08-23-2006, 09:52 AM

very detail step by step write up .... I think I am gonna give it a try also... save me a lot of trouble!!!!!

Singletrack · 08-23-2006, 01:11 PM

Thanks for documenting that - it will help with the fuel filter change at 60k miles...man I hate working with fuel.

Czarnecki · 08-24-2006, 03:59 AM

Quote:

Originally Posted by Doctor Subie

Great step by step write up, making it easy even for us mechanically challenged to do! One thing: I read on a previous Walbro install to re-use the stock filter, as it does a better job of filtering on our STI's, and to use the Walbro supplied filter if you have a WRX...link here:
http://www.iwsti.com/forums/showthread.php?t=34720

Any comments on that?

Glad you enjoyed the write up. I read the link you posted and now I understand that the bag is the STi's only fuel filter. The only downside I see of using the Walbro filter is it could allow small debris to pass through. I would like to see if anyone else had an issue with using the supplied filter or using the stock filter. Another benifit I see of using the stock filter might be that you dont have to cut the chamber at the bottom like I did to make it fit- but I already did, so I probably wont go back to the stock filter unless someone can convince me otherwise.

WolfPlayer · 08-24-2006, 01:14 PM

More information from prior writeups ...

http://www.iwsti.com/forums/showpost...8&postcount=34

t

rodent · 09-12-2006, 08:40 PM

Where did you get the new filter and sock???

08-17-2006, 03:44 PM	#1
Czarnecki Amateur STI Driver Car: 04 Subaru STi Silver Fav Mod: Headlights in the oven Location: Des Plaines, IL Posts: 21 Join Date: Jun 2006 Trader Rating: (0)	Walbro Fuel Pump I just installed my Walbro fuel pump to prepare for my DB 20G. Below are pictures to guide anyone through this process. I thought this was a pretty easy install, but I did encounter a few minor problems which were easily fixed. I am by far not a master mechanic, so if someone thinks I did something wrong, your comments are appreciated. TRM 20-AUG-2006: added to the How-To catalog sticky This ad is not endorsed by this member. Please register or login to hide this ad. Last edited by TRM : 08-20-2006 at 02:37 PM.

08-17-2006, 03:54 PM	#2
Czarnecki Amateur STI Driver Car: 04 Subaru STi Silver Fav Mod: Headlights in the oven Location: Des Plaines, IL Posts: 21 Join Date: Jun 2006 Trader Rating: (0)	The first step is to remove the rear seat, two bars, and black trunk cover. I believe 13 12mm bolts and four plastic pushins. This is what it should look like. On the passenger side, there is a 4 screw cover just before entering the trunk. Remove this to access the pump and sending unit. Now the next VERY IMPORTANT step is to unplug the white electrical connection. Once unplugged, the car needs to be started in order to relieve the pressure in the fuel lines. You will notice that the CEL and Low Fuel will light up and the car will start running bad. Eventually it will die, but I reccomend trying to restart it to ensure the pressure is out of the line. (I didnt restart and had a little gas spill in the garage) After doing this, its a good idea to unplug the negative terminal on the battery to avoid a fire because you will smell a lot of gas, expecially if you are like me and do this on a full tank . Last edited by Czarnecki : 08-17-2006 at 03:57 PM.

08-17-2006, 04:40 PM	#7
Czarnecki Amateur STI Driver Car: 04 Subaru STi Silver Fav Mod: Headlights in the oven Location: Des Plaines, IL Posts: 21 Join Date: Jun 2006 Trader Rating: (0)	For the rest of the process, just put everything back the way it was. Just be careful not to bend the sending unit arm on the way into the tank. Now you are ready for a big turbo and some injectors. Last edited by Czarnecki : 08-24-2006 at 04:04 AM.

09-12-2006, 08:40 PM	#15
rodent Professional STI Racer Car: 95 GSX Location: Highlands Ranch, CO Posts: 810 Join Date: Mar 2004 Trader Rating: (4)	Where did you get the new filter and sock??? This ad is not endorsed by this member. Please register or login to hide this ad.

08-17-2006, 04:08 PM	#3
Czarnecki Amateur STI Driver Car: 04 Subaru STi Silver Fav Mod: Headlights in the oven Location: Des Plaines, IL Posts: 21 Join Date: Jun 2006 Trader Rating: (0)	Now the three lines need to be disconnected. I used pliers to move the clamp on the two smaller lines. The third line that faces the front of the car is the high pressure line, so be carefull. I recommend placing a pan underneath the gas tank and having a large rag ready because I had a fair amount of gas come out. This connection can be taken off by hand. Remove the 8 small bolts holding the cover on. Be careful not to drop them. Now here comes the tricky part. You will need to remove a very large sending unit through a fairly small hole in the floor. Here is where you will be on your own, but it can be done. Be careful not to bend the sending unit float (a little is ok- but dont get mad at me if you damage anything). Try pivoting the unit 180 degrees like the pictures below show.

08-17-2006, 04:15 PM	#4
Czarnecki Amateur STI Driver Car: 04 Subaru STi Silver Fav Mod: Headlights in the oven Location: Des Plaines, IL Posts: 21 Join Date: Jun 2006 Trader Rating: (0)	Here is a picture of the sending unit on the workbench. I would put it in a clean pan. (I know my pan wasnt too clean) Here are pictures of the Walbro kit: In the last picture, you can see what the new pump will replace. Now the old pump needs to be removed from the sending unit. I removed the two screws that holds the bottom fuel filter chamber on. Now, disconnect the black hose from the diaphram thing to the fuelpump with pliers. Also disconnect the wires to the pump. The pump should come out with the original fuel filter attached.

08-17-2006, 04:31 PM	#5
Czarnecki Amateur STI Driver Car: 04 Subaru STi Silver Fav Mod: Headlights in the oven Location: Des Plaines, IL Posts: 21 Join Date: Jun 2006 Trader Rating: (0)	Now, the new fuel filter needs to be attached to the new Walbro pump. The kit will come with a tiny lock washer or snap ring. Be careful not to loose it. Place the filter on the pump and press the snap ring on the center part of the pump with a small socket. Make sure the snapring is all the way on. When reinstalling the new pump, I ran into a small problem. When I used the new rubber piece or pump isolator on the bottom of the pump where the fuel filter goes, I noticed that the extension comming form the pump overlapps the extension comming from the diaphram thing above it. I was unsure how to get a piece of new rubber hose to connect the two. Below are pictures of my problem. I realized that if I pushed them together, I could get them to line up. My solution to this problem was to cut the new rubber hose so that if you push it all the way on the diaphram extension, you would just see the end. Look below to see what I am talking about. After cutting the hose in the way I described, I proceded to push the two parts together like I did before when the hose wasnt on. Finally, I slid the hose over the two extensions so both had good coverage, and I tightened the hose clamps.

08-17-2006, 04:37 PM	#6
Czarnecki Amateur STI Driver Car: 04 Subaru STi Silver Fav Mod: Headlights in the oven Location: Des Plaines, IL Posts: 21 Join Date: Jun 2006 Trader Rating: (0)	The rest of this install is easy. Just remember to use the new wire provided to connect the new pump. Put everything back together except for the fuel filter chamber bottom section. I needed to slightly modify this to accomidate the new fuel filter. I needed to cut some of the plastic out including the rubber around the top of the plastic fuel filter tube, and the back two plastic tabs. Just dont cut more than you need to.

08-20-2006, 01:20 PM	#8
JJ18Sniper Silver Member Car: 05 Subaru WRX STi Fav Mod: DB 20G, Diamond Black BBS RE's, S2K retrofit Location: NY Posts: 4,594 Join Date: Jul 2004 Trader Rating: (6)	Very detailed thread, great work! I had mine installed by Tony@xxtuning in 15 minutes flat, but if I didn't have the opportunity this would have helped.

08-20-2006, 02:39 PM	#9
TRM uh, whut? Car: 04 STi Fav Mod: wdb Location: Eastern PA Posts: 2,207 Join Date: Oct 2003 Trader Rating: (0)	nice work man. i added your How-To to the Sticky! be prepared to have questions though. pics are great but you might need to give a bit of text with some of them. thanks for sharing with us!

08-22-2006, 09:49 PM	#10
Doctor Subie Junior STI Driver Car: 2006 STI OBP Fav Mod: Kartboy SS Location: Seattle, WA Posts: 164 Join Date: May 2006 Trader Rating: (1)	Great step by step write up, making it easy even for us mechanically challenged to do! One thing: I read on a previous Walbro install to re-use the stock filter, as it does a better job of filtering on our STI's, and to use the Walbro supplied filter if you have a WRX...link here: http://www.iwsti.com/forums/showthread.php?t=34720 Any comments on that?

08-23-2006, 09:52 AM	#11
esstidefi Junior STI Driver Car: 05 Subaru wrx STI Fav Mod: perrin dp /ecutek reflash/ hks highpower exhaust Posts: 54 Join Date: Jan 2006 Trader Rating: (0)	very detail step by step write up .... I think I am gonna give it a try also... save me a lot of trouble!!!!!

08-23-2006, 01:11 PM	#12
Singletrack Spec C Club Car: 04 Impreza WRX STi Fav Mod: La Quarta Stella Location: Blitzburgh, PA Posts: 1,447 Join Date: Sep 2003 Trader Rating: (2)	Thanks for documenting that - it will help with the fuel filter change at 60k miles...man I hate working with fuel.

08-24-2006, 01:14 PM	#14
WolfPlayer Moderator & ECU Tech Car: 05 CGM STI Fav Mod: mo boostaz Location: Fredneck, MD Posts: 3,703 Join Date: Jun 2004 Trader Rating: (6)	More information from prior writeups ... http://www.iwsti.com/forums/showpost...8&postcount=34 t