Flush your power steering - baby its gross in there - PeachParts Mercedes-Benz Forum

phidauex · #1 11-05-2005, 09:29 PM

Flushed my power steering system today. It took all of 10 minutes, including convincing the girlfriend to sit in the car while its running and turn the wheel side to side.

I used the method in the w123 howto sticky, and it worked great. I moved the washer fluid resevoir up and to the side, and used a gallon veggie oil bottle as the catch canister. I spilled a little fluid while removing the return line hose, but not much else. The narrow mouth of the bottle kept splashing to a minimum, even though the fluid came out in great spurts.

I flushed with two quarts of STP power steering fluid, and then filled with Valvoline Synpower and a new Mann filter. We'll see if it works. I know the manual recommends ATF, but I gather that ATF of yesteryear is different than ATF of today, and that today, PS fluid should be used instead. Hope that's true.

Point is, the stuff that came out was GROSS. Black and yucky, with little chunks. Flush your PS if you haven't done it recently!

peace,
sam

Austin85 · #2 11-05-2005, 09:31 PM

Thanks. How much PS fluid did it take to fill?
oh which one is the return line? top or bottom?

Hatterasguy · #3 11-05-2005, 09:32 PM

Yep smart thing to do, but most people don't.

Today's ATF will cause your system to leak. The ATF of 2005 isn't the same ATF of 1983, so in this case ignore the manual. PS fluid is cheap, any brand will do.

#4 11-05-2005, 09:33 PM

Great job!

I call this the ASE Test method because this is the method involved in a common question on the ASE Suspension and Steering test.

There have been a surprising number of people here who think that what you did is too involved. They think that simply sucking out what is in the reservoir and replacing it suffices as a flush.

I would think that you learned the value of your work by seeing the nasty stuff that came out of the system.

Again, great job,

Palangi · #5 11-05-2005, 09:37 PM

Y'all realize there is a filter in the bottom of the reservoir...... don't you??

phidauex · #6 11-05-2005, 10:03 PM

Quote:

Originally Posted by Palangi

Y'all realize there is a filter in the bottom of the reservoir...... don't you??

Yes, and I changed it.

Filter p/n: M2000-97891
Cost: $4.36 at Fastlane

The procedure is listed in greater detail with photos in the Diesel how-to sticky, but here is the cliffnotes version:

1: Open your power steering pump lid, set the lid and wingnut aside. Gently release the lockwasher and spring, and slide them off.

2: That thing with the holes in the bottom is the filter. Leave it in for the moment.

3: Move your washer fluid tank to the side for the moment. Put a large (at least gallon) catch container in that spot.

4: Disconnect the pump return hose. One hose has a high-pressure fitting, the other has a hose clamp. The hose clamp one is the return hose. When you disconnect it, fluid will spill from the hose, and from the pump. Catch it in your can (if you can

), and direct the hose into the catch container.

5: Have at the ready three quarts of PS fluid. Two quarts of cheap stuff, and one quart of whatever boutique PS fluid you want. I used Valvoline SynPower. They make one with a 'stop leak' stuff in it if you are having leak problems (though the stop leak things rarely stop anything but the tiniest leaks).

6: Have your beautiful assistant fire up the car, and begin turning the steering wheel lock to lock. They don't need to turn it fast, or slow, just a modest speed. As they do this, pour a quart of cheap fluid into the pump slowly, as it gets sucked through, pour in more. Then pour your other quart through. The fluid will move through FAST, so don't worry. It will also spray with some force into your catch container. I used a narrow mouth bottle to limit splashing. By the end of the second quart, your fluid should be coming out clear.

7: Have your beautiful assistant stop turning the wheel, and shut off the engine. Fish the filter out of the pump, and slide a new one in.

9: Reconnect the return hose to the pump. I used a shiny new hose clamp, since I don't trust super-old clamps.

8: Reinstall the spring and lockwasher. Pour some of your 'boutique' fluid into the pump, and let it bubble down. Add some more and bring it up to within about 1/2" of the lip of the reservoir. Fire the car back up, and have your assistant go lock to lock a few more times. This will bubble and foam as the fluid goes into the system. The level will go down, so top it back up again. Have your assistant turn a few more times, and top up again if necessary. When it stops bubbling, your system is bled. Top up one last time if necessary, and put the lid back on, and tighten the wingnut.

I ended up adding most (but not all) of a quart to the system. I don't know the exact capacity.

9: Return the washer reservoir to its nook, dispose of your bottles and filter, and have a beer. Marvel at the gunk in your catch container. Damn, that was in your power steering the whole time. Gross. Have a beer, you just spend 20 minutes on an easy task (didn't even have to bend over).

Hope that helps!

peace,
sam

Palangi · #7 11-05-2005, 10:09 PM

OK, just checking.

Carry on!

Austin85 · #8 11-05-2005, 10:17 PM

Thanks Sam.
I've got everything except the beautiful assistant....Nevermind.

Bodgit2 · #9 11-05-2005, 11:06 PM

On the 210 diesels, is the procedure the same? What mileage is advisable to do the deed? Nice description and good job btw.
Steve

bill murrow · #10 11-06-2005, 07:47 AM

I did mine using Sams method. Worked great.

I used Wally Mart brand PS fluid. Been running that for over a year with no problems.

One car I had someone had used red tranny fluid in the PS system. It leaked bad! Larry told me to dismantle it and look for grooves on the shaft. Sure enough, deep grooves galore, rendering that pump useless.

BTW.....The guy at our local repair shop gave me a quart of type F transmission fluid after I mentioned to him this is the type our PS systems require.

Cheers,

Bill

RobTheMod · #11 11-06-2005, 08:08 AM

I don't follow the ATF thing, perhaps... I understand the reformulating idea, but I'm thinking also of other cars, like a 2002 BMW 330i I checked out the other day. It says "ATF OIL" on the PS reservoir cap itself. Would you also say that that car is chewing itself up by using the red tranny oil in the PS system? It doesn't say "Pep Boys/Circle K Clear Power Steering Fluid" on that BMW cap, it says "ATF OIL". Which is what I'd put in. Likewise on my 300SD.

My other car is an Audi 5000TQ. It is supposed to use Pentosin 7.1 CHS fluid at about $20/litre. Owing to tradition, that's what I put in it. Back in the day (1996) I put PS fluid in that car by mistake. The system began to leak. I cursed the counterman who sold me that PS fluid at the time. I replaced the rack, pump, and lines, and filled with Pentosin, and it still leaked. I eventually removed the PS pump and drove with Armstrong steering. 9 more years of playing with old Audis has taught me that the system will leak no matter what you use. I keep with Pentosin- others swear that ATF works in that system, no leaks for years!

It's a side ancedote at best. But if ATF Dexron/Mercon is not fit for you guys' steering systems, I want to know what you put in your transmissions, as most of our cars are automatics...

#12 11-06-2005, 08:10 AM

Quote:

Originally Posted by Bodgit2

On the 210 diesels, is the procedure the same? What mileage is advisable to do the deed? Nice description and good job btw.
Steve

The procedure, other than Bills container in place of the windshield washer reservoir part, is the same for ANY vehicle MB or otherwise. Just remove the return line and place it in a container.

The return line deals with very low pressure as compared to the pressure line so it is usually easy to identify. USUALLY it is a simple hose with clamps rather than a hose with fittings, but not always. It also USUALLY is the highest hose on the pump.

Power Steering fluid is your best bet on most any car. If a car made from abot 2000 on calls for ATF, you can use ATF without worry. Anything much older may very well call for it, but that decision was made before ATF morphed into what it is today.

Good luck,

whunter · #13 11-06-2005, 09:07 AM

Quote:

Originally Posted by RobTheMod

I don't follow the ATF thing, perhaps... I understand the reformulating idea, but I'm thinking also of other cars, like a 2002 BMW 330i I checked out the other day. It says "ATF OIL" on the PS reservoir cap itself. Would you also say that that car is chewing itself up by using the red transmission oil in the PS system? It doesn't say "Pep Boys/Circle K Clear Power Steering Fluid" on that BMW cap, it says "ATF OIL". Which is what I'd put in. Likewise on my 300SD.
My other car is an Audi 5000TQ. It is supposed to use Pentosin 7.1 CHS fluid at about $20/liter. Owing to tradition, that's what I put in it. Back in the day (1996) I put PS fluid in that car by mistake. The system began to leak. I cursed the counterman who sold me that PS fluid at the time. I replaced the rack, pump, and lines, and filled with Pentosin, and it still leaked. I eventually removed the PS pump and drove with Armstrong steering. 9 more years of playing with old Audi's has taught me that the system will leak no matter what you use. I keep with Pentosin- others swear that ATF works in that system, no leaks for years!
It's a side anecdote at best. But if ATF Dexron/Mercon is not fit for you guys' steering systems, I want to know what you put in your transmissions, as most of our cars are automatics...

Hello RobTheMod
The easy analogy is; would you like a transfusion of red paint instead of blood??
If you where a chemical engineer, I could believe you understood reformulating an oil.
Next analogy relates to your car comparison:
Analogy #2. since you are a mammal, your next surgeon will be a Dolphin veterinary surgeon.

The car is yours, you may insert dynamite and ignite, if you choose, but do not expect others to emulate your example.

The transmission uses Dexron/Mercon 3.

The power steering systems uses clear power steering fluid or the old formulation ATF type F.