Fuel Filter Replacement on SAAB c900

I have a list of things for Greeny I'm working on. Some of the items have been on the list for a while - this is one of them. It's really maintenance, but it could be related to a performance issue as well. I suspect mine hasn't been changed for a very long time. It's one of those things that gets neglected.

Sometimes under acceleration I get a momentary stumble. I know this could be a fuel delivery issue - i.e., the fuel filter could be clogged. I just so happens I have a filter on hand, and I've been wanting to take care of this. I've had a new filter since last fall and finally I'm getting around to replacing the old one.

It's not a difficult job, just a bit messy.

First thing to do is to jack up the rear of the car. Or, if you're fortunately, get it up on a lift.

Note I have proper jackstands under the car and chocks on the front wheels. DO NOT get under the car if it's only supported by a jack! You want to be alive to drive the car after you're done.

New floor jack and jack stands.

I just retired my rusty ancient jack stands and have these "Pro-Lift" ones now. They seem to be good. There are two locks - one bar for the ratchet and a pin that passes though the entire support arm.

Also, my trusty Craftsman 2-ton floor jack went belly up last fall. I had that jack for over 30 years. It started leaking hydraulic fluid from one end of the piston. I would rebuild it, but I don't know the model number in order to get a rebuild kit.

At any rate, I sprung for this Arcan aluminum 3-ton jack. It's actually a lot nicer than my old one - has more capacity and lifts higher. The downside is that it's a lot bigger and heavier. But since it's aluminum, it's about 25 lbs lighter than it would be if it were steel - which is why I got it. It weights "only" about 60 pounds.

The filter is behind the right-side rear wheel. You can see it looking in the wheel well, but you need to be under the car to get at the fittings.

You can see Greeny is pretty rust free. Other than a couple of small spots in the engine compartment (frame rail), and the rear beam axle, the car is remarkably rust-free. Although looking at that axle made me start thinking about rebuilding the rear suspension so I could have the axle powder-coated!

The car has not been driven in winter its whole life as far as I know. The paint is shot but structurally it's in great shape.

This is the fuel filter close up.

In this picture, the left side of the filter near the spring is the passenger side of the car (it's LHD).

With the car raised up access to the filter is pretty good.

Note how I labelled the photo as to which end of the filter is which. There is also an arrow on the filter to help with getting it installed in the right direction. This shot was taken after I had soaked the fittings with PB Blaster as noted below - they're pretty clean.

There's a banjo fitting on each end of the filter.

In addition, there is a flange nut molded into the filter. The nut is there for a reason. Put a wrench on the nut to hold the filter, and then the banjo bolt can be removed.

On the interwebs you will read horror stories about rusted, frozen, stripped nuts on fuel filters. Fortunately I was lucky.

I sprayed the fittings down with PB Blaster and let it soak in for a couple hours. Then I went at it.

The nut on the filter on the inlet end is 27mm; the bolt is 19mm. On the other end, the filter nut is 22mm, and the bolt is 17mm. Put the big wrench on the filter to hold it, and lever the banjo fitting with a second wrench or ratchet.

I just "cracked" the torque on the end you see above to relieve any pressure in the line and to let some of the gas drip out. I had a rag on the axle just below the filter so it didn't splatter much, and a bucket on the ground to catch the gas. Then I let the gas drip out into the bucket for about 20 minutes before I started on the other side.

Important: wear safety glasses when you do this job. The fuel could spray, and in any event you WILL have gas that drips out. I also wore disposable gloves. It's one thing to get some gas on your skin, that's not good, but you DO NOT want to get it in your eyes. When I loosened the fittings, I made sure I was not directly under the filter.

I had to procure a new wrench for this job. Here you see my new 27mm combination wrench. The largest I had previously was a 24mm. Who knows when I'll need it again, but considering it only cost me $11 (!) at the Despot and is pretty hefty, I'm a happy boy.

After all, you can never have enough tools.

Now on to the other end of the filter.

To cut to the chase: there wasn't a lot of clearance between the outlet end and the spring, so I couldn't get a 1/2 inch drive ratchet or breaker bar onto the nut.

I couldn't budge it with my shorter 3/8 drive breaker bar, so I slipped an aluminum tube over the 3/8 bar to get more leverage. The bar was leftover from a shower caddy I installed a couple weeks ago. I thought it might come in handy, and I hung on to it.

With the "extension" I was able to get the outlet end bolt off. Sorry, no pictures, you'll have to visualize it!

After the two bolts had been freed up a bit and some gas drained off, I decided to try and loosen the bolt holding the mounting strap. You can see it in this shot - the fastener is a hex/allen screw. It takes an HW4 (I assume it's 4mm) drive.

And it came off with no problem at all.

Then I set about removing the banjo fittings all the way. More gas came out. Surprise.

I realized also after loosening the strap bolt that I probably could have slid the filter to the right, away from the spring enough to get a larger wrench on that side. Live and learn.

Here's the inlet banjo fitting removed. At this point I was breathing a sigh of relief.

I undid the other end and got ready to take the filter off.

I was able to loosen the strap enough to get the filter out without removing the screw. I was concerned putting that screw back in would be a hassle and fortunately I avoided it entirely.

Slide the filter out and hold it over your bucket.

It holds a fair amount of gas.  You can see it draining in this arty picture I took.

Then empty your bucket into another container you can seal and take to your local transfer station. I thought I might be able to put the gas into the gas can I use for my lawnmower, but it looked filthy. So disposal it will be.

The old filter is on the right and the new one on the left. Interesting that the flanged end is reversed on each one. They also carry different Bosch numbers - who knows how long the old one had been on the car. But clearly the design changed a bit over the years.

Here we have the two banjo fittings, their old copper crush washers, along with a bag containing new washers.

Don't reuse the old washers. There is a 90% chance they will leak.

One washer goes next to the hex head on the bolt, and the other goes against the filter's body.

Put it all back together. You don't need to tighten the bolts up too tightly.

Sorry for the bad photo - it was dark under there and my camera had a one second shutter speed.

Don't forget to tighten up the bolt for the mounting strap as well.

All done. Nice and clean. Too bad nobody will see it.

At this point, start the car and check for leaks. My car ran for a second on the fuel still in the line, then stalled. Then it cranked for a second and started right up.

It's running well now, haven't had any stumble. But mainly it was peace of mind to get this done.