Technical Service Bulletin Sealing the Crankcase on Oil Pipe

Subject: Sealing Crankcase Cast-on Oil Pipe Models: 911 Carrera/ 911 Turbo 1989

Bulletin Number: 89 – 11

Oil leaks from the cast-in oil pipe in the right crankcase half (oil cooler area, Figure 1) can be repaired with the engine removed or installed.

Video of TSB 89-11 Sealing the crankcase

Work Procedure

  • Remove oil cooler
  • Clean and degrease the crankcase thoroughly in the area of the pipe using acetone, alcohol, or something similar.
  • Apply a coat of Silastic 732 RTV sealing compound with light pressure uniformly until the depression is filled.
  • (Porsche PN 999.915.451.40)
  • Smoothing the compound with a water-coated putty knife or similar tool. Smoothing the compound is possible for a maximum of 5 minutes after application. Complete hardening time is 24 hours. Test running the engine will not disturb the hardening process.

Note: Replacement crankcases should be sealed in the same manner.

Sealed crankcases are installed from the production date: March 1989.

Engine Number 64 K 04.691  911 Carrera

Engine Number 68 K 01.028  911 Turbo

oil leaks can occure. Sealing the crankcase is the best answer.
You can do this TSB any time, in the car or out.

Sealing the Crankcase

Why should you seal the crankcase at this point? There is a difference in materials between the case and the pipe. The case can be aluminum or magnesium and the pipe cast in place is steel.

The two metals heat differently and can cause a weeping oil leak at this point. If it has not started, it is a small upgrade to ensure this will not be a problem for you in the future.

Important Notice: Technical Bulletins are intended for use by professional technicians, not a “Do-it-yourselfer”. They are written to inform these technicians of conditions that may occur on some vehicles or to provide information that could assist in the proper service of a vehicle. Special tools may be required to perform certain operations identified in these bulletins.

The use of tools and procedures other than those recommended in these bulletins may be detrimental to the safe operation of your vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely.

If a condition is described, do not assume the bulletin applies to your vehicle or that your vehicle will have that condition. See your Porsche Dealer for information on whether your vehicle may benefit from the information. Part numbers listed in these bulletins are for reference only. Always check with your authorized Porsche dealer to verify the correct part numbers.

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