Timing belt

Q I have a 2002 Hyundia Santa Fe with the 2.4 petrol engine and replaced the cambelt soon after I bought the vehicle. Before doing this, I noticed that, when the engine was at Top Dead Centre, the cambelt was very slack on the long side; in every other position it was taut, as it should be. The old belt was like this and the new belt is the same. Do you know why this would be as I don’t think it is right and I have

never known it on any other vehicle. The car runs fine with no issues and has done so for more than five years.

Nick Lett

A The only reasons that I can see for the belt being slack on one side is that it was either not properly adjusted or the hydraulic tensioner is failing. The slack in the belt should be taken up when fitting the belt, which should be done anti-clockwise starting at the crankshaft pulley.

The belt should be fitted by locking the hydraulic tensioner into position using a locking pin, then setting the tensioner by

turning it anti-clockwise and tightening the bolt. The crankshaft should then be turned anti-clockwise by 90° and then forward 90°; this should take out any slack in the belt. The tension should then be reset before removing the pin to allow the hydraulic tensioner to operate. After 15 minutes the engine should be rotated 720° and the timing re-checked before replacing the cam covers, etc. The pushrod protrusion from the hydraulic tensioner should be between 6-9mm. If the slack appears in the belt at this stage I suspect that the hydraulic operation of the tensioner is insufficient and the unit will need to be replaced.