Got past the ignition hump - now on to fuel supply. I didn't hear the pump cycling, jumped through the pressure release hoops (wasn't any pressure), then removed it from the tank (which had a lot of nasty crap in there - doesn't now). I can't make the pump run out of the tank either.
First question: running the pump leads to both sides of a charged battery should make it hum, shouldn't it?
Second question: What other fuel pumps deliver sufficient pressure (presumably at least 36 psi to keep up with the pressure regulator) to replace it?
I am not above using an external pump, if necessary. Who sells 'em?
Again, with these Ks, my ignorance is all but complete; any help will be much appreciated.
PDF
A long time ago I read the IBMWR tech page on replacing the now $370 BMW fuel pump with an Escort/Taurus/Mustang submersible fuel pump.
Here:
http://www.ibmwr.org/ktech/fuel-pump-install.shtml With a little research I determined that the Purolator Facet FEP 2042 is an equivalent. Just to have a spare around, I bought one on eBay for $30 a couple of years ago.
Yesterday I got back to working on my K75 project bike. I'd left the fuel pump out for quite a while and it was frozen - FARK!!!
Now I'd have a chance to see if the $30 solution would work. Sure enough, it did.
It only took a few minutes and was very easy to do:
1) Remove the old fuel pump. a) Undo the hose clamp and take the fuel hose off. b) Undo the electrical connections(7mm and 8mm) c) Pop the plastic clips at the front and rear of the mounting ring. (You don't need to undo the 8 nuts on the plastic mounting ring.)
2) Once out of the tank, slide the old fuel pump body out of the incredibly expensive rubber vibration mounting ring.
3) The diameter of the FEP2042 is much less than that of the BMW fuel pump. There's a section of submersible fuel hose that comes with the fuel pump. How convenient. I cut it's length to slightly less than the diameter of the new fuel pump, ran a nylon zip-tie through it and wrapped it around the new fuel pump and secured it with the zip-tie. With a few minutes of careful cramming I was able to get it nicely lodged in the vibration mounting ring.
4) Attach the pre-filter that comes with it to the bottom of the new pump. If you fold it up a bit it will fit nicely in the fuel pump "pocket" of the gas tank. Insert your new fuel pump assembly into the fuel pump hole in the tank and make sure the clips pop into place.
5) The nozzle on the top of the fuel pump has a slightly larger diameter than the BMW one but the hose will fit over it. The IBMWR instructions say that the BMW hose clamp is too small to work. Not true. If you drop the hose clamp on first and then slide the fuel hose on you can use the old hose clamp.
6) Wire it up. Cut the ring terminals off of the black and yellow fuel pump wires from the tank. Put female blade connectors on each wire and crimp carefully. I used bare metal ones - who knows if the plastic on covered ones would dissolve in gas. Attach the black wire (ground) to the narrower blade terminal on the fuel pump. Attach the yellow wire to the wider blade terminal.