A3/B4 Timing Belt Change Instructions (from Michigan GTG)

GoFaster

Moderator at Large
Joined
Jun 16, 1999
Location
Brampton, Ontario, Canada
TDI
2006 Jetta TDI
Big thanks to Hondo for hosting the (first annual?) Great Lakes Timing Belt GTG this weekend!

I've only seen snippets of instructions on the Internet on how to change the timing belt, nothing really complete, and not anything for the A3 / B4 models. Since my car was the only representative of the older-style engine present, I get the duty of writing this up...

Make sure you have on hand, besides the usual tools, a 10mm deep socket and a suitable tool for adjusting the tensioner (thanks to GeWilli for coming up with one). A pry-bar of some sort will also be needed, I used a tire iron. There is a special tool for turning the crankshaft, but a 13/16" 6-point socket or a 20mm 12-point socket will work also. A torque wrench is also required.

When changing the timing belt, the accessory drivebelts must also be removed, so it makes sense to change them at the same time. When ordering parts, make sure you order the correct serpentine belt and V-belt, there are two different versions depending on whether the car is equipped with air conditioning. (Yes, I got the wrong serpentine belt...) It is also convenient to change the fuel filter together with this procedure.

This procedure is intended for replacement of the timing belt with the old timing belt still on the engine (and correctly timed) for reference. If putting together the engine from scratch, or if the timing is suspected to be wrong, you'll have to follow the procedure in the Bentley manual for locking the camshaft and the injection pump with the crankshaft at TDC.

Read this procedure through carefully before proceeding. If you are not comfortable with the steps involved, have it done by a professional mechanic. The author accepts no responsibility for any errors or omissions in this document, nor will the author be held liable for any damages whatsoever, regardless of cause.

Here goes ...

1. Remove the upper and lower plastic engine covers.

2. Support the front of the car safely on jack stands with the parking brake set. Remove the right front wheel. (Not absolutely necessary, but it's easier with the wheel out of the way.)

3. Working underneath the car, loosen (but do not remove) the two bolts on the power steering pump which are located on slotted mounting holes.

4. One of the power steering pump bolts holds a bushing which contains wrench flats and a small gear. Rotate this bushing clockwise to loosen the power steering drivebelt, and remove the drivebelt.

5. Working from above, disconnect the airflow meter electrical connection (beside the air filter housing), release the clamp at the rear end of the flexible air intake duct, pull off the small black hose which connects to the air filter housing, release the clamps which hold down the top of the air filter housing, then remove the upper air filter housing, airflow meter, and intake duct as an assembly. Tape over the intake pipe that goes to the engine, to prevent stray objects from falling into the air intake (and turbocharger).

6. On top of the fuel filter, pull out the clip that holds the thermostatic valve to the filter and then pull out the thermostatic valve (plastic piece), then release the clamps for the two fuel lines that connect directly to the fuel filter and pull off the fuel lines. Make sure no dirt can enter the fuel line which goes to the fuel pump!

7. Unbolt the fuel filter and remove it from the car.

8. Release the rubber strap that holds down the lower airbox housing, then remove the lower airbox housing from the car.

9. Note the routing of the serpentine belt between the various accessory drives, for later reference.

10. Working from above, locate the spring-loaded tensioner for the serpentine belt, beside the alternator. Fit a pry-bar between the tensioner wheel and the tensioner arm, and rotate the tensioner arm clockwise to release the tension on the serpentine belt. Slip the belt off the alternator pulley, then remove it from the car. You may have to move the power steering pump forward to get the belt out from between two of the V-belt pulleys.

11. Remove the single bolt which holds the serpentine belt tensioner wheel to the tensioner arm. It is not necessary to remove the arm. (The wheel blocks access to a bolt that you'll need to get out later.)

12. Inside the right front wheel well, remove the 4 bolts which secure the external drive pulleys. The V-belt pulley will come right off, but the serpentine belt pulley will probably be stuck. It is NOT held on by the center bolt, you do NOT need to remove the center bolt, you need to work the pulley loose by some suitable means, to pull it off the end of the crankshaft.

13. Release the two clamps and one screw which hold the upper section of the upper timing belt cover in place. One clamp is easily visible behind/above the alternator. The other clamp is on the rear of the cover about halfway down. The screw is located near the center of the cover at the bottom. When the screw is removed, the clip that it goes into will probably fall off the inside; it can be retrieved later.

14. Release all hoses from the clips that are attached to the upper timing belt cover, then pull the upper timing belt cover out of the car.

15. Remove the 3 fasteners which hold the lower timing belt cover in place. One is located in a recess near the front, behind where the serpentine idler was. The second is located in a recess which is inside the round section of the cover just behind/below the crankshaft. The third is located on the back behind/above the crankshaft, You will need the 10mm deep socket to access the latter two.

16. Remove the lower timing belt cover.

17. Looking at the injection pump, note that one of the six holes in the sprocket is much smaller than the others. Rotate the engine so that this smallest hole points towards the front of the car and roughly lines up with a similar-diameter recess located on the pump housing behind the sprocket. The recess in the pump housing is visible through the holes in the sprocket. This ensures that the No. 1 piston is close to TDC so that the valve springs don't force the camshaft to a new position as soon as the belt is released.

18. Mark the cam sprocket, pump sprocket, and crank sprocket with masking tape/magic marker, or white paint, or some other suitable means, which will stand up to a bit of rough handling. Make corresponding marks on the belt (masking tape and magic marker works well), and label them "CAM", "PUMP", "CRANK" for later reference. For best accuracy, make sure your match marks are on the center-line of a sprocket tooth (i.e. on the center-line of a valley between teeth on the belt). This ensures that later on, a one-tooth-"out" condition would be visible.

19. Before doing the next step, make sure you have a suitable tool which can fit into the two small holes in the eccentric of the belt tensioner which would allow you to rotate and adjust the tensioner eccentric.

20. Remove the timing belt tensioner (note the position of the locating tang) and the old timing belt.

21. Transfer the marks you made on the old belt to the new belt. Make sure you line up the teeth one-for-one all the way around so that the marks on the new belt are in identical positions to the old belt. Double-check it, and triple-check it, and transfer the "CAM", "PUMP", and "CRANK" markings. Check once again to make sure you have everything in order.

22. Remove the small idler wheel which is between the injection pump and the camshaft sprockets.

23. Assemble the new belt and tensioner onto the engine so that the marks line up. It will take a bit of working back and forth to get it together. Don't force it, take your time. We found that it was easiest to put the upper section together with the tensioning idler loose on its mounting shaft, tape the belt in place to the upper sprockets, and then slip it over the crankshaft sprocket. It may be necessary to turn shafts back and forth in order to get everything to line up; a second pair of hands will prove useful for this. Once the belt is over all the pulleys and lines up with all the right marks, use a screwdriver to prod the tang of the tensioner into the slot that it fits into, which is towards the rear of the engine. (Some engines may use a different arrangement, mine was not quite the same as the picture in the book.)

24. Double-check that all the markings line up. Correct any problems discovered.

25. Re-install the small idler between the injection pump and cam sprocket. Tighten the mounting bolt to 25 N.m per the Bentley manual.

26. With the tang of the tensioner in place in the locating slot, rotate the eccentric CLOCKWISE using the special tool. When it approaches the correct tension, you will note that the notch in the part surrounding the eccentric starts approaching a projection on the adjoining piece. While holding the eccentric so that the notch lines up with the projection, tighten the mounting nut of the tensioner. Torque it to 20 N.m per the Bentley manual.

27. Check AGAIN that all the markings line up as they should.

28. Remove any tape used for markings on the sprockets or the belt.

29. Working at the crank sprocket, rotate the engine clockwise at least two full revolutions. If valves are going to hit pistons, it's better to find out this way than with the starter motor.

30. Install the lower timing belt cover and then the upper timing belt cover. Difficulties may be encountered when installing the front bolt of the lower timing belt cover. It works fine without that bolt in place ...

31. Press the drive sprocket for the serpentine belt into place, taking care to line up the locating dowel.

32. Install the front V-belt pulley and bolt the front pulley assembly together. Tighten the bolts to 25 N.m per the Bentley manual.

33. Install the tensioning idler for the serpentine belt. Tighten the bolt to 20 N.m per the Bentley manual.

34. Install the serpentine belt.

35. Install the power steering V-belt. Tension the belt using the geared bushing then tighten the bolts that hold the pump in place.

36. Install the lower airbox housing.

37. Fill the new fuel filter with diesel fuel to the greatest extent possible.

38. Install the fuel filter and reconnect all the fuel lines and the plastic thermostatic valve.

39. Remove the tape from the air duct to the turbo, then install the air intake duct/airflow meter/upper air filter housing. Plug in the electrical connector and the black hose at this time.

40. Check for any loose items or forgotten steps in the procedure. Double check that all hoses are clamped in place and that all bolts have been secured properly.

41. Hold your breath ... and then start the engine. It will probably run erratically and stall due to air in the fuel lines; after some cranking it should then start and run roughly for a while until enough air gets worked out. Expect lots of air bubbles in the clear plastic line until the engine has been running for several minutes.

42. Re-install the right front wheel and lower the car to the ground.

43. After a few hours of driving, it is wise to remove the upper engine cover and check that the tensioner groove still lines up with the projection, and to go after everything that has been touched as part of this procedure with a torque wrench. Then install the upper and lower engine covers.

44. Be glad you don't have an A4 model with an engine mount that has to be removed in order to change the timing belt ...

Pictures to follow, if everything works as it should.

Brian P.
'96 Passat TDI
 

GeWilli

Top Post Dawg
Joined
Aug 6, 1999
Location
lost to new england
TDI
none in the fleet (99.5 Golf RIP, 96 B4V sold)
lucky bastard
Did you checkit on the way home? I have been leary of opening it all up but I suppose I really should eh?!?

Thanks for your help brian! Your simpler setup made it possible to jump to the PIA setup!
 

GoFaster

Moderator at Large
Joined
Jun 16, 1999
Location
Brampton, Ontario, Canada
TDI
2006 Jetta TDI
Heck, a timing belt don't need no stinkin' break-in period! In the afternoon when we were doing test drives, I nailed it with Superdve's G-Tech on the windshield. No surprise ... slowest car there, thanks to no chip and being 600 lbs heavier than anything else not counting the toolbox in the trunk.

Interestingly, the car seems to run smoother and feels stronger in the mid-range compared to how it was before the new belt. I guess the timing is back to where it should be now.

Brian
 

Big Red

Veteran Member
Joined
May 22, 2000
Location
Newark, DE, USA
Great Post, I plan to bookmark this for when my tour of duty is called.

A couple of comments:

Can you edit the post to include the P/N' of the belts and the tensioner?

Step #19, please define the tool required or the diameter of the pins and the spacing so I can find a suitable tool ahead of time.

Good comments on the fact that this is a good time to change the fuel filter. Sounds like the same for the air filter and
also to knock out the SNOWSCREEN!!

Thoughts?
 

GeWilli

Top Post Dawg
Joined
Aug 6, 1999
Location
lost to new england
TDI
none in the fleet (99.5 Golf RIP, 96 B4V sold)
Big Red,

The tool was a Park Bicycle Tool Green Handle pin tool. Used for Bottom Brackets and such.

It does the job for the tensioner. I am sure the VW part is better but these can be found at any Local Bike shop, Cheap.
 

GoFaster

Moderator at Large
Joined
Jun 16, 1999
Location
Brampton, Ontario, Canada
TDI
2006 Jetta TDI
Part numbers - this is for the Passat with the 1Z engine, but I think the other models are the same:

028-109-119-P Timing belt
028-145-271-L V-belt for power steering and a/c
028-903-137-T Serpentine belt for NO a/c (i.e. the wrong part for my car!!)
1H0-127-401-E diesel fuel filter
191-127-247-A thermostatic valve for fuel filter
3A0-819-644 interior dust/pollen filter

Brian P.
'96 Passat TDI
 

Leon R

Veteran Member
Joined
Mar 20, 2000
Location
b.c. Canada
By this thread and the other one, sounds like you guys had fun!!! but...... I just got of letter from my Dealer, Mervyn Motors at Kelowna reminding me that my 80000 klm service must soon need attention. At the bottom of the letter they advertise:
fuel injection service $64.95
TIMING BELT RELACEMENT GAS AND DIESEL $189.95

Kind of wish mine was due for a timing belt change before they realize they probably made a mistake. I know that's what they charge for the old td's . from all the time and effort you guys put in its hard to believe they will do it for $189.95 !!! I don't doubt the commeraderie was worth it but....
 
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