what is this bolt for on my power steering pump - PeachParts Mercedes-Benz Forum

ray m · #1 10-16-2007, 04:20 PM

When i turn the wheels i get a humming noise from the bottom of the power steering pump. What is this bolt for. Can you drain the fluid from it. RAY M

TX76513 · #2 10-16-2007, 04:31 PM

What model is that on Ray?

ray m · #3 10-16-2007, 04:38 PM

I should know by now to at least give my model. Thanks. 1980 300d non turbo

300SDog · #4 10-16-2007, 04:39 PM

Yep, it looks like drain plug to me. Though SOP for draining power steering gearbox and pump reservoir is disconnect return line at the pump, then crank the engine.

pawoSD · #5 10-16-2007, 04:41 PM

You could loosen the belt on the P/S pump and use a drill with a 22mm socket on it to spin the pump.....that'd give you precise control over the fluid purge, and wouldn't put any wear on the starter.

TX76513 · #6 10-16-2007, 04:43 PM

Change the filter - while your in there

ray m · #7 10-16-2007, 04:45 PM

The reason I ask ,and i should have mentioned, is someone said it was a drain plug but when i removed it nothing came out. The lid on the reservoire was off. I'm kind of worried i might have tampered where I shouldn't. Thats why i'm looking for some help.

ray m · #8 10-16-2007, 04:49 PM

I changed the filter a month ago. when I got the car it had been sitting for a long time and the fluid was dark. I suctioned out as much as i could from the top of theresovire and refilled.

TX76513 · #9 10-16-2007, 04:58 PM

I never noticed if my 126 has a bolt on bottom. I cheat and use a turkey baster thing also.

tangofox007 · #10 10-16-2007, 05:00 PM

Quote:

Originally Posted by ray m

The reason I ask ,and i should have mentioned, is someone said it was a drain plug but when i removed it nothing came out.

I just spent 20 minutes looking in the service manual. And I am still not clear on the purpose of that bolt!!! But the FSM does state that p/s fluid should be siphoned from the reservoir; that pretty much shoots down the "drain plug" theory for me.

TX76513 · #11 10-16-2007, 05:02 PM

Probably a secret vacuum reservoir

ray m · #12 10-16-2007, 05:08 PM

What ever it leads to , it is empty or something because nothing came out and it worries me some.

ray m · #13 10-16-2007, 05:55 PM

Quote:

Originally Posted by TX76513

Probably a secret vacuum reservoir

Well 10 min and i flushed it from the return lin with my wife reluctantly turning on and off the engine and turning the wheel. could this bolt be a lube access or something. Still i'd think something would drain our when it was removed.

ray m · #14 10-16-2007, 06:48 PM

Quote:

Originally Posted by tangofox007

I just spent 20 minutes looking in the service manual. And I am still not clear on the purpose of that bolt!!! But the FSM does state that p/s fluid should be siphoned from the reservoir; that pretty much shoots down the "drain plug" theory for me.

Thanks for trying tangofox007 and TX76513. It seems no one else knows what it is for. I looked through my Chiltons, my Hanes manual and my Mb service manuals. M B chassie and body series123,vol 1&2. The Serv Man "Engines O M 615_617, and M B maint manual model yr 1981 -1993. All I could find was a couple of pics with the # 59 by it in vol 1 s/m chassie &body series 123 manual, but no references to the bolt that I could find. Maybe it has a purpose in another mercedes model???

Stevo · #15 10-16-2007, 08:06 PM

Quote:

Originally Posted by pawoSD

You could loosen the belt on the P/S pump and use a drill with a 22mm socket on it to spin the pump.....that'd give you precise control over the fluid purge, and wouldn't put any wear on the starter.

I like that, good idea. Much less mess