Timing

I am approaching 40k. I will probably have my belt changed very soon. My question is very simple. At 40k, I would assume that there is some belt stretch. I would also assume that this would throw the timing off slightly, possibly affecting fuel mileage. I go to get the belt changed. They lock the cam, put on the new belt. At this point isn't the new belt going to be just as slightly out of time as the old belt was when it was removed? How do you make up this slight difference in timing that occurs from belt stretch? After a few belt changes it could be way out of time. Just wondering, have no experience in this area.

<BLOCKQUOTE><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><HR>Originally posted by POWERSTROKE:
...They lock the cam, put on the new belt. At this point isn't the new belt going to be just as slightly out of time as the old belt was when it was removed? How do you make up this slight difference in timing that occurs from belt stretch? After a few belt changes it could be way out of time. Just wondering, have no experience in this area.<HR></BLOCKQUOTE>

and because it's a toothed? (just don't know the word in english), belt they will have to turn the pump a little in order to put the new belt on right teeth. That's how it was in earlier 1.6 D which is an ancestor of these new great engines. After getting the new belt on and tensioned they should check timing with VW workshops (computer)tool which name has passed my mind, 1552?...
PS. they do lock the pump too.

With the cam locked you remove the cam pulley and timng belt. Then you reinstall the timing belt along with the pulley but before you tighten the pulley you move the engine to TDC and insert the injection pump lock pin. This sets the cam in perfect time with the crank and puts the pump within an adjustable range for optimum timing adjustment. Once the engine is at TDC determined by the tick mark on the flywheel and bellhousing and the pin is in the pump, you re-torque the cam pulley bolt. You then remove the lock pins and lock plate. Then you start the car and adjust the mechanical setting on the injection pump in basic settings by loosening and adjusting the 3 injection pump bolts. The A4 has to be adjusted when the engine is off so it is a hit and miss adjustment that requires a few tries, not overly complicated.

The whole process is simple really but the dealers always seem to screw it up???? I have to say the process is time consuming on the A4's if yours is an A3 piece of cake because you can adjust the timing with the engine running saving some time in the timing process.

DB

[ March 28, 2001: Message edited by: Drivbiwire ]

[ March 28, 2001: Message edited by: Drivbiwire ]