|Customizing Your NG900 or old 9-3 This forum contains all CUSTOMIZING related Q&A's, such as Lights (taillights, headlights, turn indicators, clear corners, etc), Interior and Exterior modifications, Wiring, Gauges and more.|
|07-03-2020, 06:34 PM||#1|
Avid TSL User
Join Date: Apr 2011
Location: Mountain View, CA
Improving power steering serviceability by changing battery type
This one's a two-for: cheaply replacing a no-longer-available part of the power steering assembly with generic hydraulic hose, and replacing the heavy/bulky battery and battery tray with a smaller and lighter alternative. I did this modification to my two Viggens back in 2017 and realized I never did a writeup.
The power steering system has a combination of lines that fall into three categories:
- small, high pressure, hard lines between the pump and rack
- small, medium pressure lines between the rack and the anti-foaming reservoir
- large, low pressure supply lines between the reservoir and the pump
The high pressure lines are mostly steel. Or maybe entirely, I forget. If they leak, the failure is likely a 10 cent o-ring.
The low pressure supply line is a combination of soft, flexible hose permanently crimped to hard lines, and is not serviceable. Mine was leaking from these crimps in multiple places and needed to be replaced. At the time, in 2017, this part was not available so I had to design my own.
I took measurements of the required length and diameter, and went to Hoses and Fittings, Etc. in Fremont for advice on the correct type of hose for power steering fluid. They sold me a type of hose rated for hydraulic fluids, typically used to repair construction equipment, and a brass right angle fitting needed to make the connection to the reservoir.
It's 16mm (5/8") interior diameter. Sold by the foot, and you'll need 4 feet. I used spring clamps instead of worm drive clamps because they apply constant pressure and are less likely to weep as they get old.
Trying to get the old supply hose off the car was a nightmare. All the power steering hoses run beneath the battery tray, which is permanently attached to the frame of the car with spot welds. There's a removable battery tray insert held on with a few little M6x1.0 bolts which is basically an adapter to accommodate different standard battery sizes in different world markets, but beneath that is the non-removable part.
I did manage to get this job done in a late night of swearing and frustration, but I vowed to design a better way before I inevitably had to do this to my other Viggen, which brings us to the second half of the upgrade.
I happened to have a nearly-dead Braille B2317 AGM battery I inherited for free from someone else's project leftovers, and it happened to be a perfect size and shape to sit on the frame rail of the car. A new one that isn't ruined is about $200, not much worse than the standard battery. Be warned it comes in a mirror image configuration ending in "R", but we need the standard (left-handed) terminal layout. And a 2318 mount.
First cut out all that bracket nonsense. I used a combination of sawzall, angle grinder, and spot weld cutting drill bit.
I modified the 2318 mount with some generic aluminum angle from the hardware store. This was before I had a tig welder or knew how to weld aluminum, so I used pop rivets, but if you're a more skilled fabricator than me, you could make yours look way more slick than mine.
Fit the battery in the mount, rest it in the car where you want it, make marks on the aluminum angle where you want to drill it. Take the assembly back out and drill those holes. Then put the assembly back in and mark (transfer punch, or whatever) the location for the holes in the frame. I used rivnuts and M6 studs.
Everything got thoroughly cleaned and coated with truck bed liner to discourage rust. This doesn't matter a whole lot in California, but if you're somewhere salty, all this cutting into the metal is inviting the rust in. Truck bed spray is a great way to add protection back. No one will ever see what color the paint underneath the battery is anyways.
Here's a shot of the finished product.
To recap, here are the materials I used:
- 4 feet of 16mm (5/8") hydraulic hose
- brass 5/8" right angle adapter
- 4x hose spring clamps for 16mm 5/8" hydraulic hose
- 4x M6 rivnuts
- 4x M6 studs (the ones with etorx or external hex and a stop in the middle are best)
- 4x M6 nylock flange nuts
- Braille B2317 battery
- Braille 2318 mount kit
- aluminum angle
- pop rivets
- truck bed liner spray
- red locktite for the studs
And the tools:
- basic hand tools needed for any Saab work
- die grinder or angle grinder
- drill bit set
- spot weld cutting bit
- pop rivet tool
- rivet nut tool
- hose cutter
- remote spring clamp pliers
- local spring clamp pliers
I didn't need to buy any tools for this job. The materials were mostly the battery and tray combo (~$300) and a few bucks here and there for the rest, so I estimate about $350 total for the battery half of the job and tens of dollars (certainly under $50) for the steering return hose half of the job.
This frees up a ton of room to work in one of the most cramped parts of the engine bay. It's not worth touching if nothing's wrong, but it's totally worth it as a "while you're in there" upgrade.