Author Topic: Steering servo pump mounting  (Read 3690 times)

mbzse

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Steering servo pump mounting
« on: April 22, 2016, 12:12:27 »
Some pictures as I am refurbishing a steering servo pump. Disassembled the unit, cleaned parts and exchanged three interior O-rings plus shaft seal.
Pump is mounted in the "cradle" or bracket which in turn is mounted at the left front of the engine block. Some useful pictures by Alfred can be found in this posting:
http://www.sl113.org/forums/index.php?topic=23493.msg168037#msg168037
Pump is fastened via three bolts, two M10 and one fractional 3/8" UNC. The fractional one has a spacer bushing. Bolt is some 80mm long.
The pump slides sideways in order to tension the short V drive belt. Range of movement 0-12mm (1/2 inch). Slide is actuated by the device shown, with two M6 nuts (key width 10mm).
Once V-belt is tout, the pump is locked in position by the three bolts; the two M10 ones have to be fastened with open-ended fixed wrench (17mm) behind the belt pulley.
Somewhat tricky design. Same procedure if one wants to adjust or remove the V-belt, be sure to loosen all three larger bolts before touching the M6 nuts  8)
/Hans in Sweden
« Last Edit: April 25, 2016, 22:28:56 by mbzse »
/Hans S

ja17

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Re: Steering servo pump mounting
« Reply #1 on: April 24, 2016, 01:17:37 »
Good information Hans.  Yes the power steering pump may be one of the only places on the engine where you find fractional hardware. The 9/16" head on the bolts will easily accept your 14mm wrench, and may trick you into believing it is metric. But the threads of the bolt are not metric!
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback