BMW M52tu-M54 Camshaft Replacement Guide - Taking German Engineering to the Next Level

This procedure covers the removal and re-installation of camshafts on the BMW M52tu and M54 engines.

These instruction start from a point of complete disassembly of the VANOS drive system. For VANOS disassembly instructions please refer to steps 1 thru 48 of the “GAS BMW M54 Master Cam Timing Tool Kit Instructions“. These instructions are located in the “BMW Tool Instructions” section of the support menu.

The following tools are required to complete this procedure:

10mm socket
11mm socket
22mm socket
24mm open end wrench or large adjustable wrench

Important! Read this before using these instructions!

The camshafts in the BMW M54 & M52-tu engines are lightweight hollow castings that can brake in half during removal or re-installation if the proper procedure is not followed. This DIY procedure is a safe way to remove and re-install your camshafts without the need for special BMW factory tools.

There are other camshaft removal procedures that involve setting the camshaft rotation so that one set of lobes is placed in the maximum valve opening position, this leaves the other 5 sets in a position where the valves are closed and no pressure is exerted on their lifters.

There are three potential problems with that procedure:

The camshaft needs to be held from rotating with a wrench in one hand, while loosening the cap nuts with a ratchet in the other hand.
The nuts on the cap will run out of threads before the pressure is fully released from the cam lobes and lifters. This means that the camshaft will snap free, possibly causing the cam cap and nuts can go flying, once the nuts are completely loose.
The cam cannot be re-installed using that procedure because you cannot install the cap with 1 set of lobes in the fully open position, the threads on the journal studs are not long enough.

Our procedure involves positioning the cams so that 2 sets of lobes are set to a 30% open position and the other 4 sets are fully closed. This procedure is a little bit more time consuming, but is a safer and more controlled way of removing the cams.

Camshaft replacement is an involved and delicate procedure, and should only be attempted by persons with extensive mechanical knowledge and DIY experience. Read this entire procedure thoroughly before you begin to familiarize yourself with the process. Take your time and follow these instructions carefully. This DIY procedure is provided as a public service to the BMW community. If followed correctly, it is nearly impossible to break a cam. Since we have no control over the skill lever of the end user of these instructions, we will not be held liable for any damages or broken camshafts resulting their use.

If you cannot have a computer near by during this procedure, print off these PDF instructions.

Click on images in the instructions to view full size

#1

This should be your starting:

All VANOS sprockets, secondary chain & guides removed.
Crankshaft at Top Dead Center (TDC) mark.
Cams set to proper VANOS timing position.

Remove the camshaft lock blocks and TDC lock pin if they are still installed.

#2

Rotate the crankshaft counterclockwise approximately 45 degrees from the #1 cylinder TDC mark as shown in the picture. This will position all the pistons at a safe distance from the valves, and will prevent any possibility accidentally bending a valve during the procedure.

Make sure you DO NOT accidentally rotate the crankshaft away from this position during the procedure.

#3

If the primary timing chain is looped over the exhaust camshaft, reposition it and secure as shown to prevent it from falling into the engine.

#4

In the next step you will be rotating the exhaust camshaft. Use a 24mm open end wrench or large adjustable wrench, on the hex shaped section of the cam, at its midpoint.

Do not use the square flange at the end of the cam to rotate the cam.

#5

Rotate the exhaust cam to the angle shown in the picture.

Do not rotate more than the approximately 40 degrees shown.

In this position, just 2 sets of cam lobes are applying pressure to their lifters. This is the best position to control the movement of the camshaft as the journal caps are loosened.

#6

We are now going to take the positioning one step further than what is really necessary. This is just an added margin of safety to prevent the cam from trying to reposition itself while it’s being loosened.

Compare the height of the valve lifters at journals A3 and A5. You may need to use a penlight to see well enough. Rotate the cam a little back and forth until the lifters at A3 & A5 are both at the same height relative to the top of their bores. This sets the cam so that there is equal pressure on the both sets lobes.

#7

You can now remove the journal cap nuts from all caps except A3 and A5. DO NOT start to loosen caps A3 or A5 yet. Remove all journal caps except A3, A5 and A1. as shown.

A3 and A5 are the only journals that are carrying any load with the camshaft in this position. It’s 100% safe to remove the other caps.

#8

On occasion, the lifter block will start to rise with the camshaft instead of staying flush with the cylinder head as the journal cap nuts are loosened. This does not hurt anything, but if it does rise with the cam, it will make some of the procedure difficult.

I suggest installing a couple of hold down spacers in opposite corners of the lifter block. In the picture you can see that I used 2 small 3/8 drive sockets with cap nuts to secure the lifter block. Just finger tighten these, you don’t want to mare the cap mounting surface. Install them at A2 and A7, do not use the studs at cap A1.

This picture shows the intake cam, but the same idea can be used here on the exhaust cam.

#9

You will be loosening the caps at A3 and A5 in 1/4 turn (90 degree) increments. They will be loosened in the order shown. Do not start to loosen them yet.

#10

Using an 11mm socket and ratchet, loosen the nuts in 1/4 turn increments in the order shown in the previous picture. I’m sorry if I’m stating the obvious, but the easiest way to verify how much you are turning, is to start with the ratchet in a horizontal position and rotate until it’s vertical, or the other way around.

Read the next instruction before you begin loosening.

#11

This is the reason that you did not remove the cap at A1. By leaving the cap in place, it gives you an easy visual verification of whether the end of the cam is rising equally to the caps at A3 and A5. Journal A1 has a thrust surface that can possibly hang up when the cam starts to rise. By watching the gap here and comparing it to the gaps at A3 and A5, you can verify that the cam does not hang up on the thrust surfaces.

If the A1 cap does not start to rise right away, equal to the other two caps, give the end of the cam a little tap with a rubber mallet or your fist to pop it loose. Keep an eye on the A1 gap and compare it to the gaps at A3 and A5 until the cam is completely loose

#12

Continue loosening the nuts at A3 and A5 in 1/4 turn increments until they are completely loose. After you’ve completed two complete revolutions of each nut you can bump up to 1/2 turn increments if you wish.

Remember to keep comparing the A3 and A5 cap gaps to the A1 gap as you go. If the A1 cap does not rise equally each time you loosen the nuts at A3 and A5, stop and find out why.

#13

Once the journal caps at A3 and A5 have been fully loosened, you can remove the caps at A3, A5 and A1, then remove the exhaust cam.

#14

Exhaust cam removal is complete, it’s time to move on to the intake cam.

I know it will seem redundant, but I will be using the exact same instruction wording for the intake cam. This covers the case of someone removing the intake cam only, that did not read the exhaust cam procedure.

#15

In the next step you will be rotating the intake camshaft. Use a 24mm open end wrench or large adjustable wrench, on the hex shaped section of the cam, at its midpoint.

Do not use the square flange at the end of the cam to rotate the cam.

#16

Rotate the intaket cam to the angle shown in the picture.

Do not rotate more than the approximately 40 degrees shown.

In this position, just 2 sets of cam lobes are applying pressure to their lifters. This is the best position to control the movement of the camshaft as the journal caps are loosened.

#17

Compare the height of the valve lifters at journals E4 and E6. You may need to use a penlight to see well enough. Rotate the cam a little back and forth until the lifters at E4 & E6 are both at the same height relative to the top of their bores. This sets the cam so that there is equal pressure on both sets of lobes.

#18

You can now remove the journal cap nuts from all caps except E4 and E6. DO NOT start to loosen caps E4 or E6 yet. Remove all journal caps except E4, E6 and E1. as shown.

E4 and E6 are the only journals that are carrying any load with the camshaft in this position. It’s 100% safe to remove the other caps.

#19

#20

You will be loosening the caps at E4 and E6 in 1/4 turn (90 degree) increments. They will be loosened in the order shown. Do not start to loosen them yet.

#21

Read the next instruction before you begin loosening.

#22

This is the reason that you did not remove the cap at E1. By leaving the cap in place, it gives you an easy visual verification of whether the end of the cam is rising equally to the caps at E4 and E6. Journal E1 has a thrust surface that can possibly hang up when the cam starts to rise. By watching the gap here and comparing it to the gaps at E4 and E6, you can verify that the cam does not hang up on the thrust surfaces.

If the E1 cap does not start to rise right away, equal to the other two caps, give the end of the cam a little tap with a rubber mallet or your fist to pop it loose. Keep an eye on the E1 gap and compare it to the gaps at E4 and E6 until the cam is completely loose.

#23

Continue loosening the nuts at E4 and E6 in 1/4 turn increments until they are completely loose. After you’ve completed two complete revolutions of each nut you can bump up to 1/2 turn increments if you wish.

Remember to keep comparing the E4 and E6 cap gaps to the E1 gap as you go. If the E1 cap does not rise equally each time you loosen the nuts at E4 and E6, stop and find out why.

#24

Once the journal caps at E4 and E6 have been fully loosened, you can remove the caps at E4, E6 and E1, then remove the intake cam.

#25

You are now finished with the camshaft removal procedure.

If the camshaft removal was to be able to service the cylinder head, this is the point to go ahead with head removal. If the removal was for installation of new camshafts, go ahead and continue to the camshaft installation procedure in the next step.

#26

Before you begin the camshaft installation make sure that you have a quality brand of engine assembly lube on hand.

Make sure that the assembly lube is specifically designed for use on cams and lifters. I personally use Red Line assembly lube.

#27

Apply a liberal dab of assembly lube to all lifter faces and cam journal bearings.

#28

Thoroughly clean your new or used exhaust cam with solvent or brake cleaner and blow dry. Lay the camshaft into the cam journals as shown in the picture.

One end of the cam has a square flange. Install the cam so that the side of the flange with the 2 holes is facing up and angled toward the intake cam as shown.

Smear some assembly lube on the cam lobes as well.

#29

This is a close up view of the proper rotation of the exhaust cam for installation. In this position only two sets of cam lobes will be exerting any pressure on their lifters. This position will give you the greatest control over cam loading as you tighten down the cam.

#30

Smear some assembly lube on the bearing surface of the caps then set cam journal caps A1, A3 and A5 in place as shown in the picture. Install the 6 hex nuts and start them about 1 revolution each by hand.

#31

This kind of looks like we suddenly switched to the intake cam, but the picture is just taken from the opposite side.

Adjust the finger tightening of the six hex nuts to equalize all the cam cap gaps on both sides of the caps as shown.

#32

You will be tightening the 4 nuts at A3 and A5 in 1/4 turn (90 degree) increments in the order shown. The 2 nuts at A1 will be tightened each time, finger tight, after tightening A3 and A5 with a ratchet. DO NOT start tightening until step #34.

#33

Just like during the removal process, we are using the cap at A1 to verify the flatness of the cam as we tighten it down. The goal is to keep an eye on both sides of all 3 caps, and adjust your tightening slightly as you go to keep all gaps equal.

The reason we finger tighten the cap at A1, instead of just setting the cap in place and watching it, is to make sure that the cam does not bind up on the thrust flanges as it enters the bearing. Finger tightening allows enough force to pull the thrust flanges into place, but does not unevenly load the cam (at that end) like wrench tightening would do.

#34

Now you can tighten the 6 nuts at A3, A5 and A1, in the order shown, in 1/4 turn increments. Use a wrench or ratchet at A3 and A5, finger tighten only at A1. Watch the gaps between the caps and the head as you proceed. Adjust your tightening amounts at A3 and A5 to keeps all the gaps equal.

Pay more attention as you get close to zero gaps to make sure that the caps at A3 and A5 bottom out at same time.

#35

Once the caps at A3 and A5 have been lightly tightened down with a ratchet, you can install the rest of the journal caps and tighten them all down lightly. After all the caps have been lightly tightened you can go back and torque them all to 14Nm-10.5ft/lbs. You are now finished with the exhaust cam installation. We will repeat the process with the intake cam.

I know it will seem redundant, but I will be using the exact same instruction wording for the intake cam. This covers the case of someone reinstalling the intake cam only, that did not read the exhaust cam procedure.

#36

Thoroughly clean your new or used intake cam with solvent or brake cleaner and blow dry. Lay the camshaft into the cam journals as shown in the picture.

One end of the cam has a square flange. Install the cam so that the side of the flange with the 2 holes is facing up and angled toward the exhaust cam as shown.

Smear some assembly lube on the cam lobes as well.

#37

This is a close up view of the proper rotation of the intake cam for installation. In this position only two sets of cam lobes will be exerting any pressure on their lifters. This position will give you the greatest control over cam loading as you tighten down the cam.

#38

Smear some assembly lube on the bearing surface of the caps then set cam journal caps E1, E4 and E6 in place as shown in the picture. Install the 6 hex nuts and start them about 1 revolution each by hand.

#39

Adjust the finger tightening of the six hex nuts to equalize all the gaps on both sides of the caps at E1, E4 and E6 as shown.

The cap at E1 is not visable in the picture but needs to be adjusted equal to E4 and E6.

#40

You will be tightening the 4 nuts at E4 and E6 in 1/4 turn (90 degree) increments in the order shown. The 2 nuts at E1 will be tightened each time, finger tight, after tightening E4 and E6 with a ratchet.

DO NOT start tightening until step #42.

#41

Just like during the removal process, we are using the cap at E1 to verify the flatness of the cam as we tighten it down. The goal is to keep an eye on both sides of all 3 caps, and adjust your tightening slightly as you go to keep all gaps equal.

The reason we finger tighten the cap at E1, instead of just setting the cap in place and watching it, is to make sure that the cam does not bind up on the thrust flanges as it enters the bearing. Finger tightening allows enough force to pull the thrust flanges into place, but does not unevenly load the cam (at that end) like wrench tightening would do.

#42

Now you can tighten the 6 nuts at E4, E6 and E1, in the order shown, in 1/4 turn increments. Use a wrench or ratchet at E4 and E6, finger tighten only at E1. Watch the gaps between the caps and the head as you proceed. Adjust your tightening amounts at E4 and E6 to keeps all the gaps equal.

Pay more attention as you get close to zero gaps to make sure that the caps at E4 and E6 bottom out at same time.

#43

Once the caps at E4 and E6 have been lightly tightened down with a ratchet, you can install the rest of the journal caps and tighten them all down lightly. After all the caps have been lightly tightened you can go back and torque them all to 14Nm-10.5ft/lbs.

You are now finished with the intake cam installation.

#44

The last step is to return the cams to their normal T.D.C. position in preparation for installing the cam gears and timing the VANOS.

Using a 24mm wrench on the hex sections in the middle of the camshafts, rotate the cams until the flats with the two holes are parallel to the head surface.

Rotate the crankshaft clockwise back to the TDC position.

For VANOS reassembly instructions please refer to steps 1 thru 44 of the second half of the “GAS BMW M54 Master Cam Timing Tool Kit Instructions“. These instructions are located in the “BMW Tool Instructions” section of the support menu.