Technical Bulletin. Drive Failure due to Incorrect Tensioner set-up. Transmission : Various Fuel : Petrol. Technical Details

Size: px

Start display at page:

Download "Technical Bulletin. Drive Failure due to Incorrect Tensioner set-up. Transmission : Various Fuel : Petrol. Technical Details"

Osborne Harrison
6 years ago
Views:

1 Bulletin No. : TB0025 Issue Date : Oct 2013 Pages : 7 Subject : Drive Failure due to Incorrect Tensioner set-up Part No. : QBK538 / QTB578 Description : Timing Belt Kit Make : Mitsubishi / Volvo Engine : v(4G93, B4184SJ / M) Year : 1995 on Model : Carisma, Pajero, Shogun, S40, V40 Transmission : Various Fuel : Petrol Technical Details Drive failure on this engine is mainly caused by incorrect initial tensioner set up. Adhering to the correct and complete installation procedure for the automatic tensioner is vitally important and can avoid costly engine damage. Fig.1 Shows the Timing Belt drive lay-out of this engine, with correct position of the timing marks.

There are 2 main errors made when installing this Timing Belt and Tensioner. 1) Manipulating the tensioner correctly, but not completely following the recommended tension setting procedure.

2 There are 2 main errors made when installing this Timing Belt and Tensioner. 1) Manipulating the tensioner correctly, but not completely following the recommended tension setting procedure. This leads to incorrect tension with a premature belt failure as a result. 2) Turning the tensioner in the wrong clockwise direction. This leads to incorrect tension and very often tensioner seizure. The tensioner bracket touches the pulley preventing it from rotating freely. (Fig.2) Fig.2 Evidence of this contact can be found on the back inner side of the tensioner pulley. (Fig.3) Fig.3

Due to the partial seizure of the pulley, the belt will be constantly rubbing against the static pulley surface and will start to overheat and crack (Fig.4) Fig.

3 Due to the partial seizure of the pulley, the belt will be constantly rubbing against the static pulley surface and will start to overheat and crack (Fig.4) Fig.4 This excessive temperature is further transmitted to the tensioner and the idler pulleys, leaving a blue heat mark on the pulleys (Fig.5) and possibly even traces of melted rubber (Fig.6). Fig.5 Fig.6

4 When the tensioner pulley is turned in the correct anti-clockwise direction, it will not be able to come into contact with the adjuster bracket (Fig.7) Fig.7 QH strongly recommend replacing the tensioner and idler pulleys together with the belt, as these parts obviously also wear out. A worn bearing (loss of grease, seizure, misalignment etc.) is just as bad as a worn belt and will lead to premature drive failure, resulting in serious engine damage. CORRECT INSTALLATION PROCEDURE Removal Engine must be cold!! Remove accessory belt, tensioner/idler pulleys, engine support and timing belt covers. Put engine at Top Dead Centre, with timing marks aligned (see Fig.1) by rotating the crankshaft clockwise. Block the camshaft pulleys using the O.E. tool Volvo , or equivalent and see Fig.8 for the correct positioning.

5 Fig.8 Loosen the tensioner pulley bolt and then remove the old timing belt, tensioner pulley and idler. Check that the piston rod of the hydraulic tensioner has extended out of the tensioner body by 10.5mm to 11.5mm. If not, or leakage is present, replace the tensioner. Apply a pressure of 10 to20 Kg. on the piston rod, movement of the rod should be maximum 1mm. If more, replace the tensioner. Push the rod slowly down (Vertically) until the holes of the rod and the tensioner body are in line. Insert a 2mm retaining pin (Fig.9). Fig.9

6 Installation Ensure engine is at Top Dead Centre! Install the old/new hydraulic tensioner (2 bolts at 13Nm) Install new tensioner (mount pulley with eccentric hole at the top, 2 small adjusting holes at the bottom) and idler pulleys. Rotate the crankshaft pulley half tooth anti-clockwise. Install new belt in following order; crankshaft, water pump, idler, exhaust camshaft, inlet camshaft, tensioner. Turn the tensioner pulley anti-clockwise into the belt using adjuster tool (Fig.10) and tighten the pulley bolt temporarily. Fig 10 Unblock the camshaft pulleys and check if all timing marks are aligned. Turn the crank pulley +/- 90 degrees anti-clockwise. Turn the crank pulley +/-90 degrees clockwise till Top Dead Centre (all Timing Marks aligned). Loosen the tensioner pulley bolt. Turn the tensioner pulley using adjuster tool and a torque wrench) anti-clockwise into the belt with a force of 2.5 to 4.0 Nm. Tighten the tensioner pulley bolt (50Nm). Important: Ensure the pulley does not move, when tightening the bolt to the correct torque! Remove the 2mm retaining pin out of the hydraulic tensioner. Rotate engine clockwise 720 Degrees (2 turns) to Top Dead Centre (Timing Marks in line). Leave engine 5 minutes like this.

7 The piston rod should now be sticking out of the hydraulic tensioner body by 3.8mm to 4.5mm. If not within this value, repeat the tensioning procedure until correct position is reached. Re-install other removed parts. Summary Only work on cold engines. Always replace timing belt, tensioner and idler pulleys at the same time. Only rotate tensioner pulley anti-clockwise. Pay extreme attention to correct hydraulic tensioner set up. Follow every step in the OE installation procedure. Use the specified tools.

2005 Hyundai Tucson LX. On some models, engine is equipped with a timing belt and timing chain. Inspect timing chain when replacing timing belt.

2005 Hyundai Tucson LX. On some models, engine is equipped with a timing belt and timing chain. Inspect timing chain when replacing timing belt. TIMING BELT NOTE: On some models, engine is equipped with a timing belt and timing chain. Inspect timing chain when replacing timing belt. Removal 1. Remove the engine cover. See Fig. 1. 2. Remove right