Removal and installation the clutch slave cylinder (BMW 5 Series E28)

Hydraulic fluid is poisonous. It also dissolves paint well. Be careful not to let the fluid come into contact with exposed skin or eyes. Keep a rag handy to soak up spills, and if it comes into contact with painted surfaces, rinse immediately with plenty of cold water.

Removal

Before beginning this procedure, contact your local auto parts store about purchasing a repair kit or a new slave cylinder. Based on the availability and cost of the parts needed, decide whether to repair the cylinder or replace it. If you decide to repair the cylinder, follow the instructions included with the repair kit.

1. Remove the brake fluid reservoir cap (for left-hand drive models) or a reservoir with hydraulic clutch fluid (for right-hand drive models) and use a syringe to remove fluid from the reservoir. On left-hand drive models, the fluid level should be below the brake line connection to the master cylinder.

2. Jack up the vehicle and securely place it on axle stands.

3. Clean the area around the hydraulic line nipple and disconnect the line from the slave cylinder. Use a special wrench if possible to avoid damaging the nipple. Keep a rag handy to catch any spilled fluid. Plug the open end of the line to prevent fluid from leaking out and contaminating the line. On models where access to the slave cylinder is difficult, it is better to unbolt the slave cylinder before disconnecting the nipple.

4. Loosen the slave cylinder mounting nuts and remove the cylinder from the transmission.

Typical hydraulic clutch slave cylinder





5. Inspect the plastic tip of the pushrod and the shift lever for signs of wear. The pushrod should only be worn at the tip. The lever should only show signs of wear in the pushrod recess. Wear on the sides of the pushrod or on the lever in places other than the recess indicates that the pushrod is out of balance.

6. Inspect the slave cylinder for leaks. If the tappet seal is leaking, replace the slave cylinder. When installing a new cylinder, make sure it is the correct type. On models with a conventional flywheel, a 20.64 mm diameter slave cylinder is used; on models with a two-piece flywheel, a cylinder with a diameter of 22.2 mm is used.

Installation

1. Install in reverse order. Don't forget to apply a thin layer of molybdenum disulfide grease to the plastic tip of the pushrod and make sure that the tip fits correctly into the recess in the engagement lever. Tighten the slave cylinder mounting nuts to the required force.

2. Fill the reservoir with fresh fluid and bleed the hydraulic clutch system (see section Bleeding the hydraulic clutch system).

(This article is based on information from the website: «BMWMan»)