by "Urambo Tauro" (urambotauro)
Published 10/09/2017 at 12:00
by "Urambo Tauro" (urambotauro)
Published 10/09/2017 at 12:00
Tags: saab 900
; project
; wrenching
STARS: 8
Mistakes were made. Is it too early to start making “Saab story” puns? Not on this project.
We did know that it needed a brake lamp switch, but saved further inspection of that circuit for when the switch arrived. Fortunately, replacing the switch was indeed all that needed to be done to get the brake lamps working again.
The fuel system turned out to be... well, less straightforward. I didn’t have high hopes that the fuel pump would even work, but when I saw that there wasn’t even any power at the pump fuse, I grew suspicious.
There were probably TWO things wrong here. The fuel pump must be toast, because, well of course it’s gonna be toast after sitting for so long in Ron’s yard. And as for the power delivery issue, I figured that: best case scenario- it’d be a dirty ground. Worst-case scenario- a bad LH Jetronic module or a chewed-up wiring harness.
So we hooked up a jump-box directly to the pump wiring at the fuel tank and turned it on. Nothing. Okay, fine, I’m not surprised, we’ll put a pump in it. But after seeing slightly different pump designs online, we decided to pull the pump first to see which variation would match up.
But that meant that it was time for another special tool. Last week, to unbolt the shifter assembly, we sacrificed a 3/8 socket (no way I’m giving up a precious 10mm) by cutting off 3 of the flats to mimic Saab special tool 87 90 370. This time, to avoid tracking down Saab tool 83 94 462, we followed a tip on Saabcentral Forums to make a pump lock ring remover tool out of a PVC adapter. It worked like a charm.
My brother slid the old pump out of the tank, and...
Good golly miss Molly, what a mess. A rusty pump, a rusty float arm, deteriorated isolator bushings, and slime all over the bottom of the basket. No wonder it wouldn’t chooch. That big glob of goop at the bottom of the pump basket used to be a bushing for the bottom of the pump. Unable to find a replacement bushing, we decided that we’d take this opportunity to avoid cleaning up any of these parts, and just order a whole new pump assembly instead of just the pump motor.
Strange that the pump assembly (both the old one, and the new) includes a sending unit, though. There’s no wiring from the car even going to it. No, it goes to a standalone sending unit on the other side of the tank. So why does the pump assembly even have a float arm and resistor? Could this be some sort of multi-application replacement unit, and not the original Saab pump after all? Weird.
We managed to find a replacement pump assembly online, but before we put it in, we’ll have the option of taking off the float arm to make installation easier. Might as well, since it’s only in the way.
The tank itself had to come out, too. There was about a gallon and a half of old, stinky gas inside, some of which had congealed at the bottom, getting into the pump assembly and the sending unit tube. As you’d expect.
But before cleaning the tank out, we took a look at the sender, a stand-alone cylinder. It has some of that goop on the bottom too, but no clear way to disassemble for cleaning. Does it unclip? Does it unscrew? Does it just pop o-
Oops.
The two broken solder points are easy to identify where they had been attached to, but there’s still the issue of cleaning this one up. That leaves 3 options. Proceed with attempting to fix (and clean) this one, shell out ~$80 for a used replacement, or... figure out a way to wire the car from this 3-terminal sender to the 2-terminal one on the new fuel pump assembly and not remove that float arm after all. Tough choice.
Finally, remember that electrical issue that was preventing the pump from receiving any voltage? Yeah, turns out I made the wrong ass-umption about how this fuel system works. Unlike the domestic cars I’m used to, this car isn’t supposed to prime the system as soon as the key is turned on. No, it must first receive a signal that the engine is actually turning (either by the starter, or under its own power). There was nothing wrong with the circuitry at all! Just the pump itself. Imagine that.
"Laird Andrew Neby Bradleigh" (andymcbradleigh)
10/09/2017 at 12:07, STARS: 1
Saab = awesome :) When they work.. There’s a reason I sold my ‘96 9000 and got a Kia instead. Still love Saab though.
"Chariotoflove" (chariotoflove)
10/09/2017 at 12:16, STARS: 0
Damn. I mean, I admire your ability and determination, but I still like what I did with my weekend better.
"Urambo Tauro" (urambotauro)
10/09/2017 at 13:31, STARS: 1
I’d drink to that.