Replace - Engine Installed
TIMING CHAIN REPLACEMENT - Engine InstalledCAUTION: In order to replace the chain with the engine installed in the vehicle, the chain guides and camshaft sprockets must be in good condition. Inspect both items with the chain tensioner and camshaft cover removed prior to performing any additional work.
NOTE: A worn timing chain can result in a customer complaint of chain rattle and/or chatter. Fluctuations in timing may also occur on cars with an EZK (TZ59) ignition system, which can cause driveability or detonation complaints. When the chain wears and stretches, the chain tensioner compensates for this at the ratcheting mechanism allows movement in this manner. Should you have a customer complain of chain noise, the chain can be replaced with a service chain developed for this purpose. Follow the Action outlined below.
NOTE: Required Parts (See Figure 1). Timing Chain Replacement Kit 83 94 678. Kit consists of:
- Holder for chain (over camshaft sprocket): (Fig. 1-1) 83 94 652.
- Assembly tool for chain riveting: (Fig.1-2) 83 94 645.
- Chain breaker: (Fig. 1-3) 83 94 637.
- Chain link: (Fig. 1-4) 83 94 660.
- Chain (2.0L): 75 00 697.
- Alternative chain, open with link: 93 21 837.
- Chain (2.3L): 74 83 761.
- Alternative chain, open with link: 1993 - 93 21 845.
1. Disconnect the battery terminals.
2. Remove the ignition discharge module (IDM) if so fitted, spark plugs and camshaft cover. Place shop rags in the cylinder head to prevent debits from entering the engine through the spark plug holes.
3. Align the crankshaft and camshafts with their respective timing marks. Lock the flywheel in place using special tool P/N 83 92 987 (See Figure 2, A & B). Check the timing chain for wear by removing the chain tensioner plug with spring and locating stud (plastic) and then removing the chain tensioner. Do NOT change the position of the plunger.
NOTE: Under no circumstances should the chain tensioner extend by more than 11 mm. If it exceeds this measurement, the chain should be replaced. The tensioner does not need to be replaced (See Figure 3-A). On all 9000 models the torque stay must be removed.
4. Inspect the sprockets and chain guide for wear.
- The surface between the outer grooves of the chain guide should not indicate any contact marks. If this surface does show signs of wear, the guides will also have to be replaced (see Figure 3-B). In that instance, the repair will have to be carried out in the usual way (i.e. engine out of car).
- If the wear on both the sprockets and guides is acceptable, replace the chain as described below.
5. Cover the surrounding area of the chain with cloth. Secure the chain on both sides with tie straps (See Figure 4).
6. Separate the chain by pressing out a link with special tool P/N 84 94 637 and then use a pair of pliers to remove the link (See Figure 4).
7. Using chain link 83 94 660, join the new chain to the old. Be careful to prevent the chain from failing down and becoming entangled (See Figure 5).
8. Make certain that the new chain is properly positioned around the camshaft sprocket on the inlet side and fasten the end to the old chain.
NOTE: On 1987 and earlier cars, remove the oil pipe.
9. Fit chain support 83 94 652. Remove the protective cloth and tie straps (See Figure 6). Remove the flywheel locking tool from Step 3.
10. Holding the old chain in your hand, with the new chain resting over your hand, carefully install the new chain by rotating the engine with the crankshaft pulley bolt wrench (P/N 83 92 961).
NOTE: To avoid the chain from doubling over at the crankshaft, be sure to keep it under tension the entire time as it is installed.
11. When the new chain has been installed so that only a few links are still resting on the camshaft sprocket on the inlet side, protect the area surrounding the chain with a cloth. Remove the old chain link and chain (See Figure 7).
12. Using a chain link, join the ends of the new chain together and pull the chain around until the link is midway between the legs of the chain support (See Figure 7).
13. Remove the chain link, fit a new chain lock. (See Figure 8) and
- Check that the inserts marked with a "2" are fitted in the tool. Then, place the plate of the chain link in the tool and fit it over the link on the chain.
- Press the plate in place with a force of 10 Nm (7.4 ft lb).
14. Reverse the insert in the press tool and position it with the V-notch straight above one of the pins of the link. Using the press tool, peen over the end of the pins using a force of 15 Nm (11 ft lb). Repeat on the other pin of the link.
15. Check the riveting by using a micrometer to measure the diameter of the chain link pins. The correct measurement is 3.4-3.6 mm (See Figure 9). Remove the protective cloth. Remove the chain support, and if previously removed, fit the oil pipe (where applicable) connected to the cylinder head.
17. Fit the chain tensioner as follows:
- Prepare the chain tensioner for mounting by pressing down the ratchet and pressing in the plunger.
- Fit the chain tensioner and seal. Tighten to a torque of 63 Nm (47 ft lb).
- Place the spring and locating stud (plastic) in the hole in the chain tensioner.
- Fit the plug. Check that the O-ring is in place. Tighten the plug to 22 Nm (16 ft lb). As the plug is being tightened, the spring presses out the tensioning arm and causes the chain to be tensioned (See Figure 10).
18. Replace the torque stay. Turn the engine over one revolution and check to see that the crankshaft and camshaft are lined up with respective timing marks.
19. Fit the camshaft cover, spark plugs and ignition discharge module (if previously removed).
20. Reconnect battery terminals.