Suspension & Steering

Steering Rack Failure Diagnosis

Steering Rack Failure Diagnosis

>A local shop suggested my steering rack
>is bad, is there a way I can tell?

Procedure for testing steering rack for leaks from Porsche Tech Bulletin #9308

a. Remove both rubber bellows from the steering rack housing and push aside.

b. Clean the steering rack thoroughly in the area of the rack shaft and seals.

c. At an engine speed of approximately 1000 rpm, turn the steering to the right stop and hold there under light pressure for approximately 5 seconds (the steering wheel should not be turned so hard as to activate the pressure relief valve). Repeat the procedure with the steering turned to the left stop.

Repeat 8 to 10 times to each side.

If ATF is noticeable on the rack shaft or on the housing in the area of the pinion shaft, replace the rack. If no leaks are found, the oil on the steering rack may be from another source such as the power steering reservoir, hoses, sealing washers, etc.

A light accumulation of oil in the rack boots over an extended period (i.e., between service intervals) should be considered normal and does not warrant replacement of the steering gear. In such cases, the rack boots should be cleaned free of oil, reinstalled and the fluid level topped off. The vehicle should then be returned to the customer for normal use. In so doing, the rate of oil accumulation in the rack boots can be more efficiently determined and a possible mis-diagnosis avoided.

Repair Procedure (cont.):
Grease may be seen on the rack shaft or seals during the test. This is the lubricant used for initial assembly of the rack and must not be mistaken for an oil leak.

d. Whenever a steering rack is replaced, the two rubber bellows must be replaced and secured on the housing.

e. Whenever removing fittings or lines from the steering rack or pump, always replace the sealing washers.

David Roberts

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