Ben Franklin
Member
Ok, so had a little spare time this evening to fiddle with the poor running described above on the 2008 S2. (crappy idle, bog off idle, bog at high RPM WOT, hot start problem.
Never one to resist boxed up tool sets, I picked up a HF fuel pump pressure kit:

Pretty cheap, and came with a T fitting that was easy to splice into the hard fuel line on the pump pressure line to the fuel rail, after a little grinding on the fitting to taper the nose a bit on each end of the "T".

Once I am through screwing with diags, I will likely pull it and put a metal filter in line where it was; seems to be plenty of room.
Started bike: fuel pressure was at 12 psi or so, well below the 36 psi that the manual recommends.

Decided to pull the tank, fuel pump module and inspect:
Drained most of the gas, again:

Set tank up on a WorkMate with a towel to pull module:

Got module out; unhooked gage float before removing; maybe could have worked it out, but didn't feel like arguing with it.

Inside of tank could have been worse. You can definitely see what the fuel level was for it's six year nap: Reminder; store bikes with a completely full tank! Corrosion is above the level where the fuel level stopped.

Am considering an acid wash with Muratic acid (since I have plenty from the pool injection system.) I dont think it is terrible, but no rust/corrosion is better than some. Don't think I will coat the tank, though.
Was not too much crap in the bottom of the pump assy. where it picks up fuel. Have seen much worse, running fine.

Pump screen wasn't perfect, but for 44k miles, I thought it looked ok. Cleaned it up with a toothbrush and called it a day:
Pic is before cleaning.

Popped the fuel pressure regulator out and decided to test it. Took an air spray nozzle with a tapered tip that would seal against the left side (fuel pump side) and set the compressor to 40 PSI.

Air blew straight through the regulator (which I think acts as a pressure relief blow off valve to bleed gas back into the tank, if over pressure from the pump.) I would have thought that it should blow through at 40 psi, but restrict flow below 36 psi.
I gradually reduced the pressure to 0 by keeping the compressor off and bleeding air through the regulator. It never shut off the airflow, as pressure dropped to zero.
Decided to see if I could "unstick" the piston in the regulator.
C't'd next post, 10 pic limit.
Never one to resist boxed up tool sets, I picked up a HF fuel pump pressure kit:

Pretty cheap, and came with a T fitting that was easy to splice into the hard fuel line on the pump pressure line to the fuel rail, after a little grinding on the fitting to taper the nose a bit on each end of the "T".

Once I am through screwing with diags, I will likely pull it and put a metal filter in line where it was; seems to be plenty of room.
Started bike: fuel pressure was at 12 psi or so, well below the 36 psi that the manual recommends.

Decided to pull the tank, fuel pump module and inspect:
Drained most of the gas, again:

Set tank up on a WorkMate with a towel to pull module:

Got module out; unhooked gage float before removing; maybe could have worked it out, but didn't feel like arguing with it.

Inside of tank could have been worse. You can definitely see what the fuel level was for it's six year nap: Reminder; store bikes with a completely full tank! Corrosion is above the level where the fuel level stopped.

Am considering an acid wash with Muratic acid (since I have plenty from the pool injection system.) I dont think it is terrible, but no rust/corrosion is better than some. Don't think I will coat the tank, though.
Was not too much crap in the bottom of the pump assy. where it picks up fuel. Have seen much worse, running fine.

Pump screen wasn't perfect, but for 44k miles, I thought it looked ok. Cleaned it up with a toothbrush and called it a day:
Pic is before cleaning.

Popped the fuel pressure regulator out and decided to test it. Took an air spray nozzle with a tapered tip that would seal against the left side (fuel pump side) and set the compressor to 40 PSI.

Air blew straight through the regulator (which I think acts as a pressure relief blow off valve to bleed gas back into the tank, if over pressure from the pump.) I would have thought that it should blow through at 40 psi, but restrict flow below 36 psi.
I gradually reduced the pressure to 0 by keeping the compressor off and bleeding air through the regulator. It never shut off the airflow, as pressure dropped to zero.
Decided to see if I could "unstick" the piston in the regulator.
C't'd next post, 10 pic limit.
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