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ALH engine timing belt replacement VW Jetta TDI Golf Beetle 1998-2003: part 1/3
How to replace your VW Jetta TDI timing belt (also Golf TDI and New Beetle TDI, ALH engine 1998-2003) - part 1/3
difficulty level: 3/5
This article shows how to remove the timing belt on 1998-2003 1.9L ALH engine: Jetta TDI, Golf TDI, and New Beetle TDI.
The procedure is divided into three parts: parts 1 and 2 deal with removal of the timing belt and is also applicable to injection pump, water pump, and cylinder head removal. If you find parts 1 and 2 helpful, Timing belt part 3: installation shows how to install the timing belt on your TDI engine and final checks. It's in my premium content forum so please join our community to view and upgrade your account to premium. If you find the tips on this page helpful, please use the donation button at the top so that I can continue to keep publishing great articles! The Bentley service manual is about $80 vs. this website which has more pictures, color pictures, videos, and greater detail. Thanks in advance!
Differences between this and older writeups on other websites
The torque spec for the vertical motor mount bolt is updated to help avoid stripping, the recommended torque spec for the camshaft sprocket is raised, pictures have been added to correct a common mistake of misplacing the pump pin, you don't need a cut down an allen wrench for the valve cover, stripped crankshaft pulley bolt notes are added, counterholding method for the crankshaft pulley is different, revised VW tools are shown, and final pump sprocket timing adjustment is corrected (other writeups show it reversed which is incorrect). Misc bolt sizes and detailed torque specifcations are also listed to aid in identification.
General notes when replacing the timing belt on your VW Jetta TDI, Golf TDI, or VW New Beetle TDI: ALH engine
If you've never done a TDI engine timing belt, the main difference vs. many engines is that you must buy/make/rent/borrow the timing belt index tools. Some of the tools can be fabricated or substituted. For example, the sprocket counterholder, spanner wrench, or injection pump pin can be substituted with an equivalent tool but the camshaft tool is a fine fit and is required. The sprocket puller also makes removal quick and easy without damage to the cam.
The procedure in the factory service manual must be followed because when the timing belt tensioner is tightened, the camshaft and injection pump must stay stationary using the tools to maintain time while their sprockets rotate independently. This ensures proper timing and even tension across the belt. Unlike many engines, the TDI engine doesn't use index marks on the belt or sprockets. Do not try to use paint index marks because many user experiences have shown that this method often results in failure of the timing belt, even when done by a professional mechanic. No write up on this site uses scaremonger language. You must use the correct procedure using the correct tools. Please read all of the instructions here and in your factory service manual thoroughly before attempting the timing belt replacement. If you have any questions regarding the tips on this page or the timing belt instructions, do not hesitate to ask at the forums here: myturbodiesel.com forums. If you are not comfortable that you can successfully do this job take it to an experienced Audi or VW TDI mechanic!
Older TDI and automatic transmission TDI were rated for lower timing belt change intervals. The replacement timing belt should be rated for 100,000 miles because the new belt system uses larger rollers, bearings, and belt. Because of this, you must change all rollers, tensioner, and belt to the new style. Even if you already have the long life parts, all the idler rollers and water pump should be replaced anyways to last another 100k. All parts linked below are for the 100k mile parts.
You need a Ross Tech VCDS (computer cable and diagnostic software) to fine tune the injection timing. The injection pump pin will just set the pump to a range where the engine will start and run. If you don't have a VCDS, find someone to check and/or fine tune the injection timing when practical. It won't cause any damage to run the injection pump within the acceptable range but it'll run better if it's in time. Details are on page 2 - installation.
Tools, parts, and replacement parts cost for the VW TDI timing belt
Click the links to compare current prices and kit components, shipping, tax, etc. At a minimum, you need 1 timing belt kit with some replacement engine coolant and a timing belt special tool set.
Timing belt kit (recommended) - click the links to see the current prices for the 100k mile kits from Dieselgeek, or Kermatdi. The different kits contain different components. Because these are all well known TDI vendors, the linked generic parts are often made by the same supplier as VW and are just as good as genuine VW parts. The kits above may vary in exactly what parts are included. Below are the individual components.
CAUTION - generic parts available on ebay or other online sellers may be of questionable origin and may not be the 100k part since some similar parts are also used on other VW/Audi engines. The above linked sites are all well known and experienced TDI vendors.
CAUTION - I would never buy a timing belt kit from or any other of this seller's copycat sites. I strongly believe they are all low quality copycat parts because their retail price is usually lower than the wholesale price of high quality components! It's not worth saving $75 when it can result in thousands in engine damage! I also had a very bad experience with this seller so never again.
The metal impeller water pump is preferred because the plastic impeller water pumps sometimes fail and spin on the shaft.
Kit components (every kit is different, all required for 100k mile change interval belt)
038 109 119M long life 100k mile timing belt
038 109 243N timing belt tensioner
038 109 244M large idler pulley
058 109 244 small top idler pulley
038 109 244E small lower idler pulley
038 121 011A water pump
038 145 345 vacuum pump seal (end of camshaft) genuine VW
Also get some G12 coolant to replace lost coolant. You only need 3 liters of coolant or 1 gallon and an equal amount of distilled water for the timing belt job and to account for spilled coolant. Do not use generic green coolant, see 1000q: coolant flush for more details.
genuine VW (1 gallon size , VW #G 012 A8F A4 ) genuine VW (1.5 liter size, VW #G 012 A8F M1), available from kermatdi 1.5L size, dieselgeek (1.5 liter size, VW #ZVW 237 G12)
Always replace bolts
(quantity 2) N 106 653 01 engine mount-body bolts
(quantity 2) N 102 096 05 engine mount-engine bracket bolts
N 903 285 04 injection pump bolts (if yours are the old style stretch bolts they should be replaced, otherwise optional, quantity 3x bolts)
N 905 969 02 large idler pulley bolt
crankshaft pulley/harmonic balancer bolts (these often get stripped, qty: 4 bolts, pre 2003 cars may use a different harmonic balancer and bolts than 2003 cars) VW# n 903 396 05
small top idler pulley bolt genuine VW
n 101 725 01 (valve cover bolts)
VW special timing belt tools set:
3036 camshaft holding lock (referred to as the sprocket counterholding tool)
3418 camshaft setting plate (can also use T10098a, in this writeup I call it camshaft lock bar)
2587/T10020 2 pin spanner wrench (for tensioner)
injection pump lock pin(you can substitute this with the back end of a 6mm or 15/64 drill bit)
t40001 puller set (for camshaft sprocket)
These tools are available as a kit from Metalnerd and are distributed by dieselgeek for metalnerd. I also rent them as a courtesy service, see this page for details: myturbodiesel tool rental
If you have fabrication skills, here are pictures of the VW timing belt tools (not metalnerd) and their dimensions Your ALH engine is found in the "A4" chassis car. A3 B4 is the earlier generation car. To buy OEM VW tools, see VW snap on tools. These pictures are thumbnails, click for a larger view. Pics and measurement of TB tools by Ray_G.
Below left is an OEM equivalent camshaft tool for ALH engine made by Purple dye.
Above right are the two new style camshaft tools VW# T10098a. The silver one is a metalnerd replica and the black one is an assenmacher replica. The OEM VW tool is T10098a. You don't have to remove the valve cover to use these. This saves time and the hassle of dealing with stripped valve cover bolts. They are shown in use in the procedure section. You can find them from assenmacher or the OEM VW parts site, or the replica from metalnerd.
-5mm and 6mm ball end allen wrenches, (pictured below left). Despite what you may read elsewhere, you don't need to grind down an allen wrench for the valve cover. These are not required if using VW tool 3428.
-metric offset wrenches
-regular and deep socket metric wrenches
-T25 Torx bit/screwdriver
-regular pliers and spring hose clamp pliers (pictured right, these are optional and are remote operated)
-wheel chocks/blocks of wood, floor car jacks, jack stands
Timing belt removal and replacement procedure for VW TDI ALH engine - part 1
Disclaimer: this article is revised and updated to include the most current information but is not a substitute for the factory service manual! See the TOS Agreement for the full legal disclaimer. Although a timing belt job can successfully be done with basic tools plus the timing belt tools and basic mechanical experience, improper installation of the timing belt can cause severe engine damage so take all precautions listed in the factory service manual. If you have never worked on your car, I suggest gaining experience with easier projects first before doing something as critical as a timing belt or finding an experienced local mechanic who is willing to thoroughly read these tips.
If you wish to use a service cover, do so now. I tape an old clean towel to the fender to prevent scratches. If you have a belt buckle, jeans button, or watch, it can put scratches into the paint. Also make sure you don't have loose necklaces, hair, sleeves, etc., when working on your car, consult your factory service manual for all cautions, always wear eye protection, see the TOS for the full legal disclaimer, etc..
Some general tips: if you're not familiar with the engine bay, label each part as it's removed with tape and a marker. Don't use pencil since it wipes off. . you are not familiar with the engine bay, label each plug or wire with a piece of tape and marker, not pencil. It will make installation much easier, especially if you are doing other maintenance items over a few days.
Remove the engine cover (3x 10mm nuts). You can modify it so that it's held on by pop-off clips instead. See 1000q: engine pop cover mod for details.
Remove the upper intercooler output elbow labeled below as 1 and air filter box accordion hose 2 (2 band clamps each). Tape over the intake so nothing can fall into it. I try to avoid using paper towels because they can get pushed deeper into piping and forgotten. Tape will seal the hose tightly and not fall in like a paper towel. Now look at 3, the vacuum pump.
Set aside the vacuum line going from the black vacuum reservoir ball and remove the plastic vac line bracket (10mm x2 bolts, green in below pic). These 10mm bolts sit on top of the threaded heads of the 13mm bolts holding the vacuum pump. If you have a manual transmission car, remove the coolant glow wires and remove the center coolant glow plug using a deep socket. The automatic transmission car does not have these glow plugs. They block access to the bolts so an offset wrench is for removing the 10mm and 13mm nut/bolts. A 1/4" socket with a small joint or swivel socket will also work. You can remove the vacuum pump now or later.
If you don't have an offset wrench, you can just remove the coolant glow plug flange for access since you'll be draining the coolant anyways. I suggest draining the coolant before this step so that you don't spill coolant all over the place. (Thanks for the tip diep!)
Now move to the other side of the engine bay. Remove the coolant reservoir overflow hose and coolant sensor plug (1 and 2 in the next few pics). Also remove the 2x phillips screws holding the coolant reservoir down (yellow arrows in below pic). This is a good time to check for coolant migration, see 1000q: coolant migration for more details. Once it's loose, remove the hose underneath the coolant reservoir and tuck it to the side.
Remove the fuel lines at the fuel filter (white arrows in below pic and #3 in the next pic) and tuck one end to the side. (Later engine shown, your fuel lines will look slightly different). Also unclip them from the plastic intercooler output pipe. After removing each spring clamp, twist the hose at the connection to break the seal before pulling it off. This makes it much easier to remove the hoses and helps prevent damage to the line. If they won't come off, remove them at the engine side. Caution: the plastic T on the fuel filter may be brittle. Be gentle when removing the fuel line from it.
Note the blue and white arrows on the lines and mark which is the feed and which is the return line. Label them 1 and 2, A and B, supply and return, etc. and whatever so they are installed correctly. Diesel fuel melts rubber and asphalt driveways so wad a rag around the ends to prevent excessive spilling. Clamp or tightly wrap some clean rags or paper towels around the exposed fuel lines to avoid contamination.
Optional: change the fuel filter if it's due for its 20,000 mile change. See 1000q: fuel filter change if you need more tips.
Remove the 5mm allen bolt holding the power steering reservoir down (red arrow in the below picture, pic is from a later similar engine). Move the power steering reservoir and line around as needed for clearance but don't disconnect the lines.
In the below picture you can see a blue line on the rubber elbow hose (right side of pic) that lines up with a notch on the intake piping. Note the marks when you put the hoses back.
Optional but suggested - remove the intercooler outpipe hard pipe, outlined in light blue (1 spring clamp). This will give you more clearance. Depending on the position of the lower spring clamp, you might have to remove the passenger side headlight rear access cover. They tended to have the spring clamp tips facing down. If it's positioned correctly, use a remote operated spring clamp plier (pictured below) to remove it. Tape over the exposed coupler so nothing falls into the intercooler piping. I try to avoid using paper towels because they tend to get stuffed down the piping. Sorry for the odd picture but the rubber "elbow" hose to the intake manifold should have already been removed. Now emove the upper timing belt outer cover (5 metal clips).
If the car is not on jackstands yet, engage the parking brake, jack up the car, rest the car securely on jack stands, chock the rear wheels, and make sure the car is secure before getting under it at all. There are tips on jacking cars and making wood jack blocks at 1000q: tips for the mechanic , 1000q: making wood jack blocks. Refer to your factory service manual for your year for any differences and the official procedure. If you are not sure how to raise the car, find an experienced local mechanic or helper to assist you.
Remove the splash shield (large plastic thing under the engine) and the passenger side splash shield. (torx for lower splash shield, 2 speed nuts for side shields) Speed nuts can be removed by turning them with a screwdriver. Here is the pass side shield removed. Some replace the plastic splash shield for a metal skid plate because it provides protection against road debris and potholes from hitting the aluminum oil pan. See 1000q: skid plate for more details.
Put a few drops of PB blaster or liquid wrench penetrating lubricant under the heads of the (4x 6mm) harmonic balancer pulley/crankshaft pulley bolts. This will make them easier to remove later. Don't remove the bolts yet, the picture below is just to point the bolts out. Let them soak since PB blaster needs time to soak and penetrate into the threads.
Remove the serpentine belt by releasing the tensioner clockwise with a wrench, outlined in green below. Your fingers could be pinched if the wrench or tensioner slips while you are removing the serpentine belt so be careful. While you are under there, you should also consider tightening the AC compressor pulley, see 1000q: AC compressor nut for more details and why. The AC nut is the center nut on the funny looking pulley at lower right of the picture.
Above the car....
If you have VW tool# 3428 (pictured earlier) you can leave the magnesium valve cover (VC) on.
If you don't, you have to remove the VC. Remove the VC bolts (5mm allen bolts x7) and loosen the crankcase ventilation (CCV, looks like hockey puck) hose on top of the valve cover. If the VC can't be removed by hand, use a block of wood to gently tap the edge of the VW. Don't hit directly on the valve cover with a metal hammer. You don't need a special stubby allen bit cut down. A ball end allen wrench (pictured right) will get to the hard to reach bolts. After removing the cover, try to keep the cover on if you're leaving the car alone for a while. This will keep dirt or tools from falling inside and helps keep moisture out. The rubber VC gasket is not available separately from the metal cover and should be reused.
If your car is a manual transmission, put the car in neutral so that the engine can turn over. Since you chocked the wheels and applied the parking brake the car won't roll away.
Set the TDI engine to top dead center (TDC)
There are 3 checks for TDC: the #1 camshaft lobes (on the timing belt side) should be pointing upwards like a V when viewed from the side of the car, the groove in the end of the camshaft for the vacuum pump is horizontal, and the TDC stamp on the flywheel is lined up with its index mark. These are detailed in the next few steps.
Set the engine to top dead center TDC by turning the 19mm triple square bolt on the crankshaft. Note: the car should be in neutral when you turn the engine over or else the transmission will hold the engine. Do not apply strong force to the crankshaft bolt like an impact wrench because it's a one use only torque to yield "stretch" bolt. It's safe to use the bolt to turn the engine over by hand because the force is low compared to the bolt's torque value and this is how the service manual says to turn the engine over. While you could also turn the engine over at the camshaft sprocket using a counterhold bar, this is not recommended. Despite having more teeth engaging the timing belt, it pulls on the tensioner side of the belt instead of the water pump side of the belt. This stresses the tensioner so don't turn it over there unless you're discarding the tensioner. Do not use the injection pump sprocket or water pump to turn over the engine (I don't even think it's possible but just mentioning it so you don't find a way!) Another reason is because if the serpentine belt is still on, the crank sprocket is where the timing belt is normally "turned" from, not the camshaft sprocket.
Both of the camshaft #1 lobes (closest to passenger side on a North American left hand drive car) should be pointing up in a "V" shape, brake booster vacuum pump slot at the other end of the camshaft should be horizontal (marked with red lines in the pic below). The reason why the camshaft lobes should be pointing up is because this shows they aren't pushing open the valves. The camshaft lock should fit in the machined slot at the end of the camshaft. If the camshaft lock is in and the #1 lobes are pointing up, the TDC mark on the flywheel (shown in the next few steps) should be close to the viewing window on the transmission. If you see the TDC mark and the #1 lobes are pointing down, rotate the camshaft 180o until you see the TDC mark on the flywheel again and #1 lobes are correct. The camshaft rotates once for every two crank rotations.
If you're using VW tool# 3428 you can't see the lobes since you didn't remove the VC. If the injection pump pin goes in or is just a hair off you are at TDC. If it's not even close you aren't. This assumes the engine was previously running (not an engine with the timing belt off or new camshaft).
Unbolt the vacuum pump (13mm x3 bolts) and move it to the side. Two of the bolts held the vac line support bracket from an earlier step. Pictured below are the bolt locations. Ignore the removed coolant hoses, they are for another procedure.
At the end of the camshaft is a slot parallel to the valve head cover flange. In a later step, you will insert the camshaft lock bar into that slot and shim it with business cards or feeler gauges to center it. This is pictured in the appropriate step. Do not torque the camshaft lock bar or use it to counterhold the camshaft sprocket or timing belt because it can break the camshaft or tool! The service manual says that if you use the camshaft lock bar to torque, "camshaft damage will usually result", the metalnerd tool also says "not for torque".
Now look below the coolant glow plugs and the coolant flange. Remove the rubber plug on top of the transmission bellhousing. (red arrow, similar engine pictured below, yours looks a little different)
Turn the engine slowly until the TDC index mark that's stamped onto the flywheel is centered in the window. I painted mine red for faster identification. The pictures below show a manual transmission. If you have an automatic transmission, TDC is shown in the illustration below - the "0" and dashed stamp should be at the frontmost edge (closest to front of car) of the rectangular hole and not the center. Below right is a flywheel removed from the car w/red mark. On a manual transmission car, you won't be able to see the "0", you'll only be able to see the stamp. Again, if you see the TDC flywheel stamp but the #1 camshaft lobes are pointing down, just turn the engine 180o until you see the flywheel stamp and the camshaft lobes are pointing up like the picture above.
Page 2/3 of ALH engine timing belt DIY