Thursday, April 3, 2008

Fuel pump housing fix

Disclaimer: use extreme care when working on your own car. This is not an official how-to. Its just here to show you a fix I implemented. Do this at your own risk, and KNOW what you're doing!

While putting in a Walbro 190 fuel pump a while back, I accidentally over-torqued the nut for the positive wire of the pump and I ended up shearing off the brass threaded stud that it attaches to on the pump housing (you'll see what I'm talking about in the pics below). This stud sticks off of a brass fitting that is held in place by a grommet and sealed on the top with some sort of sealant. The plastic grommet keeps the connection isolated from the housing and the rest of the chassis so it won't ground out and cause a short. Here's what I did to fix it:

1. I used a dremel tool to get out the sealant on the top side of the wire and drilled through the brass fitting on the inside of the wire terminal. Note the other two wires that still have the sealant over the connection. That's what it looked like before I butchered it.
IMG_0176.jpg IMG_0176.JPG image by stringfrIMG_0178.jpg IMG_0178.JPG image by stringfr

This view shows the underside where the stud used to be. Again, a proper connection can bee seen next to the one I drilled out.
IMG_0186.jpg IMG_0186.JPG image by stringfr

2. Next, I found a properly sized brass machine screw to insert through the fitting. I made sure that ALL the sealant was ground away over the wire terminal so that the head of the machine screw would make solid contact.
IMG_0190.jpg IMG_0190.JPG image by stringfrIMG_0191.jpg IMG_0191.JPG image by stringfrIMG_0194.jpg IMG_0194.JPG image by stringfr

Here you can see the screw coming through on the underside. I think I ended up using a longer one so more threads were exposed
IMG_0200.jpg IMG_0200.JPG image by stringfr

3. I soldered the screw to the wire terminal
IMG_0201.jpg IMG_0201.JPG image by stringfr

4. I got my multi-meter and checked the resistance from the screw to the wire feed from the fuel pump relay. I compared this with the resistance found in the connections that were still OEM. They were the same. Then (VERY CRUCIAL STEP), I checked the resistance from the screw to the housing to make sure the connection was isolated. You do NOT want a short happening here (you know, with how flammable gas is and everything).
IMG_0205.jpg IMG_0205.JPG image by stringfrIMG_0206.jpg IMG_0206.JPG image by stringfr

5. I then sealed the connection on top of the housing with JB weld. Surprizingly, with the way JB settles in it looks almost OEM. (okay, not quite...but it looks ok and will seal it really good)
IMG_0208.jpg IMG_0208.JPG image by stringfrIMG_0209.jpg IMG_0209.JPG image by stringfrIMG_0215.jpg IMG_0215.JPG image by stringfr

That's it! Waayyy cheaper than buying a new pump housing, and it took far less time than hunting a used one down. You can find all the parts necessary at Home Depot or Lowes. I've been running for a few months with no problems after doing this fix.
IMG_0216.jpg IMG_0216.JPG image by stringfr

1 comment:

Mairi said...

Keep up the good work.