Aaron K limitedslip.net


more forgotten posts: fuel system

In the process of reinforcing the rear sway bar brackets, I had to remove the fuel tank for safety (welding nearby). Of course, when I did, it was found to be not only full of rust (not surprising given the car is nearly 30 years old), and the stock lifting pump inside had broken off one of the power leads and was no longer functioning. Not to mention the in-tank filter was nearly completely clogged:


This probably explains while the external high pressure pump was whining pretty badly.

Well, couldn't put it back together in that state, so I derusted the tank with electrolysis (fun, and safe!), changed the fuel filter, removed the old lifter pump, old external pump, and installed a new in tank high flow TRE pump to replace both of them. Pretty straight forward, only complication was dealing with the large 12mm fuel line that ran between the two pumps. On the tank side, a new barbed fitting was brazed into the old large line to ease hooking up the new pump. On the outside, a reducing barbed fitting was used.


You can see the new brass fitting in the top pipe. Ignore the short chunk of fuel line on the return line - I accidently tore a small hole in the pipe removing the support between the new. Not a big deal, as it isn't under much pressure.

I actually got this all together and working properly when I discovered I should have used submersible fuel line and not regular fuel injection line. The submersible line is design for fuel contact both inside and outside. While I had it out, I also added some fuel resistant padding around the fuel pump (instead of the unknown foam that came with it). I'll definitely need to keep an eye on this for any issues down the road, but it can easily be inspected by just removing the fuel gauge sending unit and looking into the tank.

And, this pump is good enough for turbo levels of power. :)


Filed under: BMW 633 CSi No Comments

front rebuilt

I totally failed to get any pictures here, got lost in the process of trying to get it done so I could drive it instead of working on it.

The front went back together easily, and now has:

  • Flushed power steering
  • All new steering tie rods, idler arm, etc
  • New upper and lower control arms with poly bushings
  • Steering strut spacers (correct for lowered geometry)
  • Offset camber plates (non adjustable)
  • Suspension techniques sway bars in the new Energy Suspension brackets
  • H&R springs and Bilstein sport shocks to match the rear

And a completely redone brake system:

  • e32 (1990) 735 front rotors/calipers
  • e34 (1994) 540 vented rear rotors/calipers
  • rebuilt calipers, parking brake
  • new e32 (1989) 735 master cylinder
  • flushed out with Ate super blue (before it disappeared!)

And the whole thing aligned by the guys at Johns Frame and Alignment (highly recommended).

The brake upgrade is pretty amazing for just using larger parts from other cars, and was really cost effective since most of the parts came from the junkyard (but were rebuilt by me).

Very pleased to be able to drive it now, just needs a few minor tune up items including new plugs, running some Seafoam cleaner through it.

And, to top it off, I was able to sell the old seats and old wheels for nearly half the cost of the vehicle.

Filed under: BMW 633 CSi No Comments