Balance Shaft Belt Installation – 2.5L NA

Overview

Installing the balance shaft belt on the Porsche 944 (8-valve engine) is essential for restoring engine balance and preventing vibrations after belt replacement or maintenance. Proper installation ensures the belt is correctly tensioned and aligned, avoiding premature wear or engine damage. This guide provides a step-by-step procedure for installing the balance shaft belt, tailored to pre-1985.5 (1983–1985.5) and 1985.5 onwards (1985.5–1988) models, based on standard practices and cross-referenced with Porsche 944 resources. Note that balance shaft belt installation is typically performed alongside timing belt installation due to shared components.

Pink and blue text represent links to additional resources, tools, parts, and partner websites.

Tools Required

• 10mm (3/8 inch) wrench
• 13mm (1/2 inch) wrench
• 17mm (11/16 inch) socket and ratchet
• 19mm (3/4 inch) socket
• Torque wrench (capable of 20–50 Nm / 15–37 ft-lbs)
• Crankshaft pulley tool (flywheel lock or equivalent)
• Balance shaft belt tension gauge (optional, for precise tensioning)

Parts Required

• Balance Shaft Belt: 944 102 219 02 (All 1983–1988)
• Tensioner Stud (Pre-85.5): 944 102 216 01 (1984.5–1986; recommended for replacement)
• Balance Belt Tensioner Roller: 944 102 025 07 (All 1983–1988; replace if worn)
• Balance Belt Roller: 944 102 277 06 (All 1983–1988; replace if worn)
• Balance Belt Gear Woodruff Key: N 012 708 2 (2 required, All 1983–1988; replace if damaged)
• Crankshaft Woodruff Key (5mm x 5mm x 22mm): 900 117 036 00 (All 1983–1988; replace if damaged)

Required Additional Procedures

Steps in these procedures are required to complete this process:

• Timing Belt Installation

Step-by-Step Procedure

Step 1: Verify Component Condition

1. Inspect the balance shaft sprockets, crankshaft, and rollers for damage or wear. Ensure the balance belt tensioner roller (944 102 025 07) and balance belt roller (944 102 277 06) spin smoothly without noise.
2. Confirm the balance belt gear woodruff keys (N 012 708 2, 2 required) and crankshaft woodruff key (900 117 036 00) are properly seated and undamaged. Replace if necessary.

Step 2: Install the Balance Shaft Belt

3. Follow this link to ensure this step – Timing Belt Installation – of the process is followed accurately to prepare the engine for balance shaft belt installation, including aligning the timing marks and installing the timing belt.
4. Route the new balance shaft belt (944 102 219 02) over the crankshaft sprocket, then around the lower and upper balance shaft sprockets, ensuring the belt teeth engage properly.
5. Keep the belt slack on the tensioner side (right side of the engine, driver’s side in the U.S.) for adjustment.

Step 3: Tension the Balance Shaft Belt

6. Adjust the belt tension based on your model year:

If installing a new tensioner stud (944 102 216 01), torque it to 30 Nm (22 ft-lbs) using a 13mm (1/2 inch) wrench. Verify the stud length (101 mm or 106 mm for early models).

Tighten the eccentric tensioner roller using a 17mm (11/16 inch) socket, turning clockwise until the belt deflects approximately 5mm (0.2 inches) under moderate thumb pressure midway between sprockets.

Turn the spring-loaded tensioner adjustment bolt with a 19mm (3/4 inch) socket to achieve the same 5mm (0.2 inches) deflection under thumb pressure.

7. Rotate the crankshaft two full turns using a 19mm (3/4 inch) socket to ensure the belt tracks correctly and timing marks remain aligned.
8. Recheck the belt tension and adjust if necessary. If using a tension gauge, aim for Porsche-specified tension (consult the workshop manual).

Step 4: Reassemble and Test

9. Reinstall the front engine covers and crankshaft pulley as part of the Timing Belt Installation procedure.
10. Lower the vehicle from the jack stands and reconnect the negative battery terminal using a 10mm (3/8 inch) wrench.
11. Start the engine and listen for abnormal noises from the balance shaft belt area. Shut off immediately if any issues are detected.

Post Procedure Checklist

• Confirm the balance shaft belt (944 102 219 02) is properly installed, with correct tension and alignment.
• Verify the tensioner stud (944 102 216 01) was replaced for Pre-85.5 models and torqued to 30 Nm (22 ft-lbs).
• Ensure rollers (944 102 025 07, 944 102 277 06) and woodruff keys (N 012 708 2, 900 117 036 00) are in good condition.
• Check for smooth engine operation with no unusual noises or vibrations from the balance shaft belt.

Sources

• Clark’s Garage (for part numbers and tensioner stud details)
• Pelican Parts (for standard installation procedure and tensioning specifications)
• Porsche 944 Workshop Manuals (for variant-specific tensioner details and torque values)
• YouTube (for visual reference of balance shaft belt installation)