For 1981 to 1985 Turbo Diesel - common oil leak area
This o-ring has to be tough enough to handle the high heat at the injection pump. If you see oil leaks around the area of the rack damper (located on bottom at rear of injection pump) then replace this o-ring.
617 Turbo Diesel Rack Damper Bolt (Idle Stabilizer) O-ring Seal
$4.25
SKU:
DSL-COMRDBS 
Product Details
Also recommend when replacing the rack damper with the upgraded bolt. O-ring is now included with our rack damper bolts. To order a new adjusting bolt look below to order.
Location of o-ring on bolt:
Related Products:
$69.95
Currently out of stock.
617 Turbo Diesel Rack Damper Bolt With Special O-Ring
IMPORTANT NOTE: if you have a W116 300SD your engine may or may not have this part located on the rear of the large fuel injection pump. Early engines did not have one. YOU MUST LOOK THE THE BACK OF YOUR INJECTION PUMP BEFORE ORDERING
FITS THE FOLLOWING: all 123 and 126 chassis, Idle Stabilizer For 1981 to 1985 Turbo Models only 300D 300CD 300TD 300SD.