Replacing Cybrid power steering brushes

After several thousand miles a steering light may come on and your XT6’s power steering may experience a strange series of short yet increasingly frequent failures. This can be quite unnerving when taking an exit off the freeway or driving down the twisting ramps of a parking garage. If you’ve ever driven a car without power steering you know it’s hard… driving one with powersteering that has failed is arguably harder. The reason for this is that rather than just manually turning the steering mechanics of a car designed without power steering, you are now doing just that, but you are having to do it by forcing the power steering fluid through the system without the aid of a pump. Not all that easy. If your XT6’s power steering has been out for a few days or even a few weeks you will start to really feel it in your shoulders and back!

Usually this is caused by worn brushes in the power steering system’s motor. However, there are a few things to rule out in trouble shooting the power steering system before you can assume it’s the motor’s brushes.

  • Subaru issued a recall on the power steering system that most XT6’s have had done. You can tell if your XT6 has had the recall by looking for a long blue wire (about 12-18″ or so) running from the power steering pump to a wiring assembly near the driver’s side hood hinge. If you do not see this wire chances are your car hasn’t had the recall done. It has been said to be a recall that can be done anytime and doesn’t have to be done by the original owner. For more specific information on the accuracy of this, contact your nearest Subaru dealer.

  • Check for burned out fuses, shorts, or other wiring issues.

  • Check for leaks of the power steering fluid.

  • Check to make sure the power steering fluid is yellowish in color. The XT6’s power steering system absolutely must use genuine Subaru Cybrid power steering fluid (Subaru part number K0209A0080). This fluid, which has a golden color, has a chemical makeup that is different from standard power steering fluid, you know, the red stuff. Standard power steering fluid will work just fine for a while, but will definitely cause failure of the system’s “O” rings and consequent failure of the entire system. Even though the Cybrid fluid runs about $20-$25 a liter, it’s a lot cheaper than a new power steering system.

If all these things are ruled out, then you can rest assured it’s most likely the brushes in the power steering pump’s motor. Once your XT6 has accumulated more than 70,000 miles or so it is quite likely the brushes have worn down and aren’t making good contact with the commutator of the motor. New brushes can be shipped to your door from Anthony’s Subaru in Kelowna, BC for far less than what most US dealers charge. Replacing them is pretty easy.

One of the first things you should do is locate the secondary hood support location on the passenger’s side strut tower. This allows the hood to be raised wide open to almost 90° from horizontal. In this picture the power steering pump assembly can be seen about a foot or so to the right of the support pole, just behind the intake hose. The reason you want to use this positioning of the hood should be obvious. If it’s not, go ahead and postion it the normal way - you’ll figure it out after that first good bump on the forehead!

A clearer picture of the pump assembly

Before starting the repair disconnect the battery! If you don’t disconnect the battery you risk electrical shock and potential damage to the pump. Notice the scars on the end plate - I forgot to disconnect the battery first and when I lost my grip on a wire it essentially welded these grooves instantly into the endplate. Snap, crackle, pop. Fortunately my pump wasn’t damaged and I didn’t get zapped. (Note the blue recall wire.) Once you have diconnected the battery it’s time to disconnect the wires from the pump motor. Make sure you mark the wires to indicate the points to which they will need to be reconnected later. Keep track of the nuts and washers - if you misplace a washer it probably won’t really make much difference but it’s best to try to keep things in the same order going back on.

Once you have removed the wires, it’s time to loosen the nuts on the bolts holding the pump in place. There are six of them, with the two middle most bolts being noticably different. It’s difficult to describe how they’re different other than to say that they have a lip just behind the threaded area.

Once removed you can tilt the motor up and carefully rest it on the intake hose. (Notice in this photo the different middle bolt with the lip toward the end.) Take care not to let it suddenly shift and slam into its former resting place or any other hard surfaces… there are large magnets inside that could crack which would effectively render the pump/motor assembly useless. The unit is heavy and part of this weight is these magnets. The next step is to remove the endplate.

Looking at the edge of the endplate as it joins the main portion of the housing you will see a small notch. If you gingerly insert and twist a flathead screwdriver in this slot, you will ease the endplate from its normal closed position. The cast metal endplate is relatively fragile and can chip apart in places with too much force (this is especially true for tapping it back into place). It can take a bit of wiggling to get the end plate off the bolts. Be careful not to force it off or you may end up stripping the threads of one or both of the bolts.

When removing the endplate you’ll notice that it will feel as if it’s hung up on something. It’s actually being pulled toward either or both of the two powerful magnets inside the housing. The endplate should pull out the entire motor assembly from the housing. At this point it is rather critical to keep the end of the housing tilted up slightly to keep fluid from leaking into the motor housing. If some does get into the housing it can be wiped out with paper towels. (I prefer to use the thick, blue paper shop towels.)

One thing that will become very clear as soon as you remove the motor from the housing is that there is a lot of fine black powder inside. Although it looks and feels exactly like toner from a copier it’s not - it’s actually dust created by the long term wearing down of the power steering motor brushes. It does behave almost exactly like toner powder, however, in that it will easily get on everything and make quite a mess. It’s not a bad idea to vacuum this residue out if you have a vacuum cleaner that has a decent exhaust filter. Visible just to the right of my thumb is one of the brushes (small rectangular copper block) and the nut which secures the wire leading from it to the electrical connection on the endplate.

Once the endplate has been removed from the motor, you can easily loosen the nuts holding the brush wires. Flex the springs back and the brushes should easily come out. Installing the new brushes is merely the opposite set of steps. In this photo you can see the extent of wear over thousands of miles. Not too bad really considering how long the brushes have been wearing against the commutator of the motor. On average it seems most XT6 owners need to replace their brushes at about 75,000-100,000 miles.

While I have the motor out of the housing I like to take sandpaper and shine up the contact area on the motor just a bit to ensure good contact with the brushes. This isn’t a necessary step, but it can’t hurt and may help.

Once the brushes are back in the endplate, the rest is simply a reversal of the entire process. As you are putting the motor back in don’t be surprised when it is suddenly grabbed by either of the large magnets inside the housing. Simply slide the motor the rest of the way into the housing and make sure it seats snugly in the recepticle spot in the far end. When placing the endplate back on the housing, use only hand pressure. I used a “phillips hammer” (using the butt end of a phillips head screwdriver as a hammer) to tap mine back into place and ended up craking out the center section. The cast metal is VERY thin and fragile. If you absolutely must tap on it, I suggest using a rubber mallet and strike only the edges using light force. Fortunately a long time XT6 board member, John Long was able to very, very, very generously give me a replacement motor. Without his help I would have been in a real pickle… Thanks a billion, John! In fact the reason I have a picture of two separate brush assemblies is because one is from my old pump and one is from my current one that John sent me.

Once the endplate is back on, reposition the motor on its mount and bolt it into place, reconnect the electrical connections, check the fluid level (as some may well have leaked out), and reconnect the battery. Start up the car and check to see if your power steering functions normally. You should be good to go.

That’s about it for replacing the brushes!

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This page was most recently modified on Thursday, September 21st, 2017

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