I put together a step-by-step on how I diagnosed the Power Steering (PS) problem in my 2002 Odyssey. Here are the symptoms of the problem:
1) A whining or "whirring" noise coming from the PS (Power Steering) pump.
2) Foaming from the PS pump reservoir (almost like shaking a bottle of Coke, then opening it). This symptom is hard to catch unless you are looking for it.
3) The PS fluid goes low after adding fluid to the PS tank and driving around a bit.
-First, I checked if the PS belt was properly tightened.
- I looked for any obvious signs of a leak in the pump and hoses with the engine idling and with the engine off.
- With the engine off, I made sure the PS fluid level is per spec. Then while looking into the PS reservoir, I started the engine. The fluid started swirling around like a margarita in a blender. This was a good sign. I knew if I heard sucking noises from the reservoir, then I either have too little fluid in the reservoir and/or there is an obstruction or leak in the return line to the reservoir. At this point I would have drained the system, cleaned the mesh filter at the bottom of the reservoir and found the obstruction/kink/leak in the return line before I went on.
- I noticed that although the PS fluid was swirling, it started looking like air was being whipped into it. I asked my wife to turn the steering wheel lock-to-lock and the fluid started foaming like crazy. It foamed out of the reservoir and continued foaming several seconds after the engine was turned off.
-I also noticed a coating of some fluid around the back and side of the steering pump. It had turned black from collecting dirt. I thought it was motor oil but this fluid was very sticky. 100% Simple Green (a strong detergent spray) will melt motor oil dirt, but it will barely budge old PS fluid, so I knew I had a very small leak somewhere around the pump.
The area pointed out in red (see attached pictures in the next post) is low pressure and could suck air into the pump body if there is even the slightest leak in the sealing O-ring (yes, cold weather may be enough to open up the gap and let air in). The O-ring has a “bump” shaped into it (again, see the pictures). Honda loves these special O-ring shapes, but that “bump” could cause problems. First, the area is at a low pressure, so if you get a leak in the O-ring, it will suck the air in (and any quick fix <FROWN> sealant you use will be useless unless you apply the sealant OUTSIDE the pump at the o-ring joint! Joking aside, this might actually work in an emergency). Second, I don’t think the four bolts on the cover that holds the o-ring to the main pump body adequately clamps the “bump”.
The sucked in air mixes with the PS fluid and churns it into foam. The foamy fluid gets pushed into the steering rack and returns to the reservoir and back into the pump where it gets even more air churned into it (think Cool Whip). If the leak is small enough, you won’t get dramatic foaming, but your fluid will look like a dark milkshake when you look into the reservoir. Most notably, your PS pump will probably make some noise because there is some air in the fluid (and we know that air and fluid pumps don’t mix <smiley>). As the leak gets progressively worse over time, the pump will get noisier as the fluid gets enough air into it to foam out of the reservoir, just like when you open a shaken bottle of soda (thus your fluid level goes down). When you shut the engine off, the fluid settles down (within 5 minutes) and looks normal again, but with less fluid in the reservoir. Also, with the engine off, whatever fluid that remains in the pump starts to leak ever so slowly out of the same area where the pump sucks in air when it is running. That is how I was getting the fluid film around the pump!
You could fix this three ways: If you hate working on cars, go to the dealer ($400+??). If you are nervous about taking apart the PS pump then buy and install a reman pump ($124). Or if you are like me and think of working on cars as a hobby, then rebuild the pump ($15 + 20 minutes of your time after you remove the pump from the car). If you rebuild and it doesn’t work, then you are only out $15. However, you could save over $100 if the rebuild works.
First and foremost, if you follow the instructions below, then you are assuming any and all damages and risks associated with it. I did this to my PS pump and I am just sharing that knowledge with you.
The rebuild is very easy. This post took longer to write than the rebuild!
1) I bought the O-rings 13, 15, 16, 17 (see pictures) and two bottles of Honda PS fluid from Majestic Honda. The dealers are the only ones who carry these O-rings. I also replaced the O-ring on the high-pressure hose just to be safe.
2) I loosened the PS belt and took it off the PS pulley. I didn’t have to take it out of the crankshaft pulley; I just let it drop on the engine mount.
3) I felt for any looseness on the pump bearings by feeling if there is any axial or radial play on the shaft. I heard no grinding noise when spinning the pulley so the bearings were ok. All I heard a soft “swishing” sound but that is ok. A grinding noise or looseness in the shaft indicates a total PS pump replacement or a means to press out the bearing from the main pump body.
4) I found a clean spot to disassemble the pump!
5) I got ready to catch PS fluid and then removed the pump from the car
6) I didn’t remove the PS pulley because I didn’t replace the main bearings or the front oil seal. However there was no leak indication on my front seal so I was comfortable leaving it alone.
7) I removed the 4 bolts that hold the pump cover and the one bolt that held the PS fluid inlet to the main pump body. I carefully separated the main body from the back cover, making sure that the main pump components stayed together with the back cover to prevent the main pump from coming apart! It would be bad news if the main pump components came apart accidentally because the pump vanes have already worn themselves a comfy spot in the pump rotor. In my industry we call these components a "matched set", never to be separated unless being replaced.
8) Using the exploded diagrams as reference, I used toothpicks to pry and remove the Orings so that I didn’t scratch up the pump sealing surfaces. I then replaced the aforementioned Orings and used fresh Honda steering fluid as lubricant on the Orings.
9) I made sure everything is clean, especially around the sealing surfaces. Assembly was reverse of disassembly. I remounted the PS pump on the van and tensioned the PS belt to proper specs.
10) I drained and flushed the system per previous posts on this wonderful forum.
11) I bled the PS pump by slowly turning the steering wheel lock to lock several times. I now enjoy a very quiet PS pump and saved over $100 in the process.
I didn’t have a manual, so I guessed on the torque for the bolts. If someone was kind enough to look up the torque specs for the 4 bolts and the fluid inlet bolt, it would be much appreciated.