w123 power steering pump - how does it tension? - PeachParts Mercedes-Benz Forum

WhoWhat · #1 05-01-2009, 06:50 PM

I am finishing up replacing all my belts (this, after the alternator pulley saga) on my w123.

I'm done, except for the tension bolt on the power steering pump. I backed it all the way out when I was taking the belts off, mostly b/c I wasn't exactly sure what I was doing.

Now that I'm putting it back, the bolt doesn't seem to be "biting" into anything inside the housing.

Is there supposed to be a but or some sort of threaded housing part that grabs the bolt on the way in? The pump needs to come "up", meaning away from the ground, in order to tighten the belt.

Right now, the housing looks smooth inside, and the bolt obviously threaded, but nothing else inside the housing that would seem to hold the bolt tight.

Not sure if this is making sense...c'mon...help me finish!

moon161 · #2 05-01-2009, 06:59 PM

1 Pivot bolt, 2 or 3 pinch bolts, 1 tensioner. Should screw in from the top. I forget much beyond that.

WhoWhat · #3 05-01-2009, 07:02 PM

Quote:

Originally Posted by moon161

1 Pivot bolt, 2 or 3 pinch bolts, 1 tensioner. Should screw in from the top. I forget much beyond that.

Right - but what are the components of the tension "system?" I mean, I have the bolt, and the place in the housing where the bolt inserts...but nothing biting the threads on the inside of the housing, thereby causing the housing to move and tighten the belt.

What's inside the housing?

Cr from Texas · #4 05-01-2009, 07:26 PM

I've never backed mine out far enough to loose the bite.
Hopefully someone will answer that knows the details.
If I were in your shoes and didn't get a better answer, I'd try to find a way to use leverage to move the pump to a better position and see if I could recover the bite. If that fails, I'd be taking things apart to figure out how it works assuming I dropped a nut out of position.

hangit · #5 05-01-2009, 08:33 PM

Does anyone know how the steering pump is listed on the Epic system? It might show how the tensioner bolt is attached to the pump. I could not find the pump in any of the "46" steering parts section.

John

WhoWhat · #6 05-01-2009, 08:53 PM

Quote:

Originally Posted by hangit

Does anyone know how the steering pump is listed on the Epic system? It might show how the tensioner bolt is attached to the pump. I could not find the pump in any of the "46" steering parts section.

John

Ditto that...I couldn't find it either. That was the first place I looked.

hangit · #7 05-02-2009, 09:42 AM

Found it! In Epic choose major assembly M, engine; 13 Refrig, compressor, power steering.

Hope this will help you.

John

toomany MBZ · #8 05-02-2009, 10:21 AM

The bottom of the tension bolt fits into a slot type of area, so when you turn it, it pushes away from the engine.

fruitcakesa · #9 05-02-2009, 01:20 PM

On my 240 the tension adjusting bolt is threaded into a plastic slider piece that moves the PS pump as you tighten the adjuster bolt. Mine was broken and so the bolt just spun. I believe I bought a new one from MB

NCfriend · #10 05-04-2009, 10:23 PM

I am no expert but I am in a similar fight. I lost the bite on one of my compressor bolts and did not realize until everything else was tight = making it impossible to line up that last bolt.
I recommend loosen the other two bolts nearly all the way, remove the belt (a major source of tension), and try to find the properly alignment on that third bolt before putting the belt back on.

If you or someone reading this thread can recommend a less frustrating way for me to get a new compressor belt easily onto both grooves, please do!

I can also share a pic of that adjustment bolt from the PS, an inside view if you'd like to see; I have a donor car with the PS pump removed.

WhoWhat · #11 05-05-2009, 12:36 PM

Quote:

Originally Posted by NCfriend

I can also share a pic of that adjustment bolt from the PS, an inside view if you'd like to see; I have a donor car with the PS pump removed.

That would be great, thanks.

For the compressor, I accidentally removed a bolt when I should not have...this caused my compressor to "twist" a bit, while still being in the approximate proper placement. When I went to put the belt on, I could not get it on.

I ended up loosening the bolts again, then gently pressing up from the bottom of the compressor, while a helper looped the belt on. Then, I tightened everything down.

The new belts (all four are new, now), are all nice a neat, and I'm a happy camper. The compressor belt might be a little too tight, but I'm thinking it will stretch a bit over time. I check it almost every time I turn my car off.

When you get a chance, post that pic...thanks.

AMH · #12 05-06-2009, 02:45 PM

On the 617 turbo diesel engines it's a good idea not to have the belts super tight. It puts undue strain on the crankshaft pulley, which in turn, strains the crankshaft center bolt.
When you tighten up the adjusting hardware, it will tighten up the belts even more, so it's a good idea to leave just a tad bit of slack.

WhoWhat · #13 05-06-2009, 10:15 PM

Quote:

Originally Posted by AMH

On the 617 turbo diesel engines it's a good idea not to have the belts super tight. It puts undue strain on the crankshaft pulley, which in turn, strains the crankshaft center bolt.
When you tighten up the adjusting hardware, it will tighten up the belts even more, so it's a good idea to leave just a tad bit of slack.

There is a bit of slack...I suppose there could be more. The compressor belt is the tightest, but still has a little give to it.