BMW 540i (E39, pre-VANOS) Maintenance: - Intake System Gaskets and seals - Valley pan Breathing new life into your M62's leaky intake system, and fixing that nagging valley pan coolant leak. BACKGROUND At around 82k miles my engine was clearly showing signs of minor air leaks in the intake system: rough idle when cold, occasional miss at idle, periodic extended cranking times during starting, etc.
Note that a good majority of the required parts had to be special ordered, so plan your time accordingly. The entire job took me just over six hours and included taking numerous photos for this writeup and a trip to the dealer since I hadn't planned on the valley pan heat shield being too brittle to swap to the new pan. Additionally, I made several stupid mistakes (hey, I had pneumonia when I did this work, so cut me some slack, ok?) which are noted in the text by "Dork Alert!".
momentarily seal it and the RPM will increase for a short time. Note this is not a guaranteed method, and you can make a mess of your paint if you get the spray on the wrong areas. The information provided here is supplemental and is not intended to be used as a sole guide when performing the tasks described. By providing this information I accept no responsibility whatsoever for your safety or the success of your work.
On this page you'll find all the parts (with prices!) that I replaced during this job. Additionally, I've included lists of special BMW-supplied tools, and general tools I used. Be sure to read the section following these tables... REQUIRED PARTS These parts should be good for all model year E39 540/6s with build dates from 6/96 to 9/98, but you should verify with your parts department when ordering.
O-Ring, vent pipe front seal 11-61-1-745-195 1 3.05 O-Ring, ASC throttle body 13-54-1-747-475 1 2.75 Covering Cap, valley pan heat shield 13-71-1-741-097 4 0.21 ea. Coolant 82-14-1-467-704 1 gal. 25.30 Screw-type hose clamps, small local auto parts supply 3 Total $254.
Loc-Tite or equivalent (I always use the blue stuff) various bolts/nuts (see text) A word about the prices I bought most of these parts "on a whim" while at San Diego BMW - my regular dealer is Cunningham. I did not research the prices, since the total amount isn't very high. However, after seeing that I was charged $25 for a gallon of coolant, and knowing that I paid around half that the last time I purchased coolant at Cunningham, I suspect I may have been suckered.
Main Task Sub-Task TIS Procedure or Notes Battery, etc.
On this page we'll attend to all the items which need to be disassembled to allow removal of the intake manifold and valley pan. Most of the required parts... note that I didn't realize the heat shield would be so brittle, so didn't have one on hand prior to beginning work. Originally developed and published here by unknown author: http://members.cox.net/rlacm/IntakeIndex.htm Recovered and published by BMW-Planet.
Disconnect battery positive lead. - make sure your seats/mirrors are in their #1 saved position so you can return them after reapplication of power. Remove engine cover. - Note that I realized three of the four foam donuts that sit on the cover’s mounting pegs were gone - I later found them sitting down on the intake manifold.
Disconnect and remove flex line between MAF and ASC throttle body. - release hose clamps on both ends (A) - reach underneath and disconnect flex hose from intake resonator box by supporting resonator while steadily pulling up on underside of hose (B) Engine Cover Supports - Carefully disconnect red snap fitting at throttle cables (it will probably break) - remove four 10mm bolts, two on each support (A). Don’t drop bolts.
intake manifold and two on fender well). Place removed hoses in a clean environment - ie., inside a large ziplock bag. Driver’s side electrical harness - remove valve cover plate (A) - carefully pry up two small plastic covers to gain access to mtg bolts. Remove 10mm bolts. Pry plate away from valve cover with hands. Remove and set aside. - disconnect coils (B). On each of four coils, lift silver-gold connector lock clip, then disconnect harness connector from coil.
the cover comes free. Allow cover to simply lay on head at this point. Originally developed and published here by unknown author: http://members.cox.net/rlacm/IntakeIndex.htm Recovered and published by BMW-Planet.
Accelerator Cables - move main throttle lever backward with one hand while disconnecting both accelerator and cruise control cable ends from lever - the plastic retainers unsnap forward (A). - remove throttle cable bracket from front of throttle body - 2x T30 Torx bolts (B). This way you don’t need to readjust the cable position when you’re done. - move ASC throttle lever (C) (on underside of secondary throttle body) backward (clockwise looking down) to create slack in the ASC cable.
Passenger side electrical harness - remove valve cover plate (A) (the BMW plate) - same as driver’s side. - disconnect coils - same as driver’s side. - disconnect circular knock sensor harness (B) and crankshaft position sensor harness (C) - lay each harness out of way toward front of motor. - remove two 10mm nuts (D) attaching harness cover head. Set nuts aside. - disconnect harness cover from fuel injectors.
Vacuum Control Plumbing - locate black pipe that runs front/back along upper driver’s side of intake manifold. Remove single 10mm bolt (A) holding bracket at front-center of intake manifold (note: rear bracket should already be loose when driver’s harness cover was removed). - follow black pipe rearward - it connects to a rubber hose, which in turn runs into a ‘T’ connector (B). The hose that runs from this ‘T’ over to the rear of the intake manifold must be disconnected at the manifold (C).
Engine Vent Tube - PITA Alert! The vent tube is located under the intake manifold (dotted lines in photo), runs along the driver’s side head/block, and connects the block to the intake manifold. This tube must be disconnected from the intake manifold prior to the manifold’s removal. - Remove the driver’s side air duct between the cabin air filter box and firewall at the filter box, release the retainer strap, then rotate the duct 45 degrees counterclockwise and pull forward away from the firewall.
Intake Manifold - Find the vacuum line that runs from the fuel tank breather valve (A) (pete's T) under throttle body and over to left-lower corner of throttle body. Disconnect this line (cut/remove factory crimp connector) at the throttle body (B). - There are ten 11mm nuts (C), five per side, retaining the manifold. Remove each one, one at a time, being careful not to drop them down into motor. - Remove each of ten mounting spacers from studs (C).
4. Now "unfold" the driver’s wire harness/box, laying back in its original position. Carefully continue to work the manifold forward until it is clear of the wiring harnesses and remove from vehicle. Work slowly and ensure the manifold assembly really is disconnected - there is nothing worse than thinking a part is free, moving it away from the car only to have a wire or tube catch and yank it out of your hands, causing it to crash down on your bodywork. Set aside. 5.
At this point, inspect the area around the valley pan - that black plate is a plastic heat shield which snaps to the pan. The retainer clips will undoubtedly break when unsnapped, so plan on replacing the shield if you replace the pan. If you see any trace of (dried) coolant in this area, replace the valley pan. In fact, given that the plate and heat shield only cost about $50, you should replace them as a preventative measure while the manifold is off.
Valley Pan - Clean up as much gunk from the area around the valley pan and intake ports as possible. The intent is to avoid contaminating the remaining coolant which will be exposed once the valley pan is removed. Of course, it is imperative to keep debris from entering the intake ports during this operation. A small screwdriver is useful for loosening the gunk, followed up with a shop vac (don’t hoover up the paper towels from the intake ports).
VALLEY PAN INSTALLATION Valley Pan - Spend a bit more time cleaning up the area, keeping debris from entering the coolant in the block (and the intake ports). Carefully clean the valley pan sealing surface - use a light solvent (eg., WD40) on a paper towel to wipe clean. I also ran a piece of 2,000-grit sandpaper over this surface as insurance. The surface should be nice and shiny when suitably clean.
Water Manifold - Clean and inspect the two water pipes. Pay particular attention to the ends where the o-ring seals will be positioned. Use very fine sandpaper (eg., 2,000 grit) to clean up the ends as necessary. - Clean and inspect the manifold and engine block mating surfaces (A). Remove any remaining gasket material and ensure these surfaces are spotless - you really don’t want a leak here after everything is buttoned up.
1. Insert one bolt into the driver’s side upper mounting hole of the manifold. Install one gasket onto this bolt - gasket only fits one way (hold manifold such that bolt doesn’t slide out, and gasket doesn’t fall off). Position manifold on engine block and start threads of first bolt - get it threaded maybe 3-4 turns. Be careful not to let the gasket fall off or the bolt slide out - if this happens you’ll spend ten minutes fishing it off the top of the header.
Originally developed and published here by unknown author: http://members.cox.net/rlacm/IntakeIndex.htm Recovered and published by BMW-Planet.
Originally developed and published here by unknown author: http://members.cox.net/rlacm/IntakeIndex.htm Recovered and published by BMW-Planet.
INTAKE MANIFOLD DISASSEMBLY AND SEAL/GASKET REPLACEMENT Vacuum Plumbing - Locate the black vacuum pipe/hose assembly which came away from the car with the intake manifold. Follow the hose to where it connects to the lower right corner of the primary throttle body (A). Remove this hose (cut/remove factory crimp connector) and separate the vacuum plumbing from the manifold. Secondary Throttle Body Disassembly - Remove three T-30 TORX bolts hold secondary throttle body to main throttle body (B).
Rear Manifold Cover - Remove vacuum hose (A) between fuel pipe and rear cover (leave attached to diaphragm on fuel pipe). Using a baggie and zip tie, seal off this hose (on fuel pipe side). - Remove seven T-30 Torx bolts (B) from rear cover. - Carefully break the seal between rear cover and manifold. Pull rear cover back and off of manifold. Originally developed and published here by unknown author: http://members.cox.net/rlacm/IntakeIndex.htm Recovered and published by BMW-Planet.
Engine Vent Pipe - The vent pipe runs up thru the center of the intake manifold, between the front and rear covers. It attaches to the rear cover via a rubber grommet, and clips into the front of the manifold. Gently press this retaining clip (A) inward toward the center of the pipe to release, and push the pipe out thru the back of the manifold. Note that this pipe is telescopic - it comprises two sections which join in the center and allow the pipe to expand slightly.
Miscellaneous - Remove the front and rear seals from the Intake Manifold. - Remove o-ring from front of primary throttle body. Originally developed and published here by unknown author: http://members.cox.net/rlacm/IntakeIndex.htm Recovered and published by BMW-Planet.
- Remove the o-ring from the front of the vent pipe. - Remove black vent pipe seal (black) from inside center of rear cover (A). - Remove vent tube seal (blue) from lower driver’s side corner of rear cover (B). - Remove brake booster grommet (red/orange) from rear cover (C). Originally developed and published here by unknown author: http://members.cox.net/rlacm/IntakeIndex.htm Recovered and published by BMW-Planet.
Originally developed and published here by unknown author: http://members.cox.net/rlacm/IntakeIndex.htm Recovered and published by BMW-Planet.
This completes disassembly of the intake manifold. Clean all components thoroughly, noting the following: - Use Simple Green, water/laundry detergent mixture, or a mild automotive parts cleaner to loosen grime from all components. Rinse with fresh water. Originally developed and published here by unknown author: http://members.cox.net/rlacm/IntakeIndex.htm Recovered and published by BMW-Planet.
- Avoid getting water/cleaning solution in vent assembly on rear cover. - Avoid getting injector nozzles in intake manifold ports wet (not a disaster if this occurs). - Ensure all sealing surfaces are perfectly clean - especially the intake manifold runners and front/rear cover seal grooves. - Dry all parts with forced air or lintless cloth/paper towels. When all components are perfectly clean and dry, continue with reassembly. Originally developed and published here by unknown author: http://members.cox.
INTAKE MANIFOLD SUBASSEMBLY Vent Tube - Carefully install new o-ring into front of vent tube, apply light coat of lubricant to o-ring, then install vent tube into engine block. Push tube all the way toward front of engine. Dork Alert! Make sure spring clip is removed from tube - if you leave it on tube it will be virtually impossible to retrieve it once intake manifold is installed. Vent Pipe - Carefully install new o-ring onto front end of vent pipe; lightly lubricate.
NOTE: refer to previous photo for locations of these seals. - Working from the front of the intake manifold, reach into manifold and gently grasp rear half of vent pipe. Push pipe backward (telescoping it slightly) onto rear cover seal, ensuring pipe is completely seated at each end. Primary Throttle Body - Install new seal into front face of intake manifold - ensure seal is properly seated.
Intake Manifold Seals - Turn manifold assembly upside down and install four new seals into mating grooves, positioning each seal so that the section which connects the seals is on the outer edge of the manifold. PITA Alert! During installation of the manifold these seals may fall out of their grooves. Be sure they are correctly seated prior to final positioning of manifold. At this point we’re ready to reinstall the intake manifold. Reinspect all work completed thus far, as a final check.
both visually and by touch! - Carefully lower manifold onto engine block/heads. - Install ten new mounting spacers, repositioning manifold slightly and as necessary to attain correct alignment. - Install ten 10mm hex nuts onto mounting studs, snugging each. - Torque each nut to 22Nm, working from the center outward. Vent Tube Installation - Position a large flat-blade screwdriver on front edge of vent tube (accessible at front/lower/left corner of intake manifold).
Vacuum Plumbing Installation - PITA Alert! Access is difficult for this step. Pre-adjust a small screw-type hose clamp and, using a pair of needle nose pliers, position clamp over nipple at lowerleft corner of primary throttle body (B, 1st photo pair) so that screw will be facing up on the left side of nipple. Locate vacuum line from fuel tank breather valve (A, 1st photo pair) (pete’s T) and working from under secondary throttle body, press hose onto nipple and into hose clamp.
Originally developed and published here by unknown author: http://members.cox.net/rlacm/IntakeIndex.htm Recovered and published by BMW-Planet.
Passenger side electrical harness Installation - connect electrical connectors to main and secondary throttle position sensors (F). - connect electrical connector to fuel tank breather valve (E) (driver’s side front of engine block) - connect harness cover to fuel injectors. Align each of the four connectors to the injectors and firmly press the cover down using both hands. - install two 10mm nuts and two washers (D), attaching harness cover head, making sure cover is correctly aligned.
Accelerator Cables - Insert ASC cable into mounting lug (D) on secondary throttle body. Move ASC throttle lever (C) (on underside of secondary throttle body) backward (clockwise looking down). Feed cable thru slot in lever and snap barrel end into lever. Release lever, ensuring cable is correctly positioned. - remove two T-30 Torx bolts (B) from primary throttle body and install throttle cable bracket, replacing Torx bolts.
Driver’s side electrical harness - connect electronic harness to rear-most fuel injector (E). - connect harness cover to three foremost fuel injectors. Align each of the three connectors to the injectors and firmly press the cover down using both hands. - Install cover using two 10mm nuts and one washer (D) (front mounting post), making sure to capture the rearward bracket of the black vacuum pipe’s rearward bracket on the rear mounting post. Tighten nut at front vacuum pipe mounting bracket.
Fuel Lines - Remove baggies and zip ties from four fuel lines and from hose at left-rear of fuel pipe. Install fuel lines (on my motor the ends of the hoses with the yellow marks connected to the car-side of the fuel system, red marks to engine side). - Connect rubber hose from end of fuel pipe to fitting on upper-left corner of rear intake manifold cover. - Reinstall driver’s side cabin air duct. Engine Cover Supports - Using four 10mm bolts (A), install engine cover supports.
Idle Control Valve - Insert grey ICV bushing into throttle body. - Position ICV and rubber mounting clamp (C), carefully capturing mounting ears of clamp in bracket. - connect plumbing (B) (at both ends) running between valve and intake flex hose. - connect wire harness (A) to valve connector. Coolant - Loosen vent screw at top of radiator tank and in front of expansion tank fill pipe. - Slowly fill expansion tank with 50/50 mixture of distilled water and BMW coolant.
Connect battery positive lead. - After power is reapplied, turn key to RUN position but do not start engine. - Store current seat/mirror settings to #1 position (#2 and #3 will be lost). Reset clock, calendar, and speed limit gong. Reinitialize sunroof. Start Engine, Check for Leaks - Start engine and allow to idle. Note that it may be difficult (eg., 5-10 seconds) to get motor running initially. - Quickly observe motor, listening for vacuum leaks and looking for coolant leaks.
- Set fan to minimum speed (not "off"). - Start engine, and immediately: - quickly rev engine to ~ 4,500RPM and immediately allow return to idle, - repeat 2x. - Stop engine. - Observe coolant level, adding 50/50 mix as required. Repeat engine startup/rev/stop/coolant level check procedure until no more coolant is needed. - Tighten expansion tank cap and reset cabin temperature controls to desired settings. With engine OFF, complete final visual inspection of all work.
