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Otto Mueller sent in this sequence on rebuilding an XK150 Brake Servo.

(Click on any image to view a larger version)

Parts ready to be plated,(yellow zinc,w/extra process to prevent rust). Parts were painted 20yrs.ago w/zinc chromate primer, it held up & still no rust Looking into vacuum chamber after slave cyl. body is bolted on. Plate on bottom for retaining return spring for main cyl. piston. Large hole for vacuum, small hole for push rod,operating main cyl.piston. Chamber walls are coated w/special grease. Return spring for main cyl. piston, located on retaining plate. Had to use old gasket on main cyl.
Complete assy. for main vacuum cyl. Push rod, operat. main cyl. piston, adjust. nut, locating wash. inner pist. plate, leather cup, outer plate, wick around pist.ring. Main cyl. assy. held in place, showing end stop for main cyl. assy.,plain wash., shakeproof wash.,nut,(securing main pist. assy.) copper gask. & nut on push rod.
Here can be seen the adjustment part of the piston. After loosening the nut on the push rod, the slotted end of the push rod is turned right to close the gap or left to open the gap between rod & piston in the slave cyl.
banjo bolt, copper washers for top & bottom of banjo
Banjo for engine vacuum hose, installed. Hole above bolt for attaching brake line from master cyl. Chrome fitting in front for brake line to 5 way junction on chassis after the piston is inserted, these are the parts that are inserted into the hydr. cyl.
New gasket came w/hydr. rebuild kit. Large hole for vacuum path to air valve, smaller hole to the right is for piston on diaphragm which controls air & vacuum.
The pieces for the air valve portion of the servo. Had to use the old diaphragm, that part no longer available. Still looks useable. Valve piston & new seal installed
Air valve body,balance spring under diaphragm.
Air valve housing & cover attached to slave cyl. body, also shows hose for connecting main cyl. to valve cover new rubber bushings for rear mounting bracket.
Rubber bushings installed on rear support plate.
Rear support bracket installed. New 1/2" rubber braided hose from banjo to fitting at rear of intake manifold, for vacuum.
Restored & completed unit secured in it's location above left side battery box.
Another view of mounting location on battery box


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