2013 BMW 750li (F01) Headlight Lens Replacement DIY Procedure – July 2019

Problem: Headlight lenses looked terrible with surface cracking and discoloration. 

Solution: The BMW dealer estimated to replace the adaptive headlights completely plus labor would cost several thousand dollars.  They said the lenses were not replaceable without replacing both of the full headlight assemblies with new lenses attached.  Also, the lenses were too far gone to benefit from “polishing” them to restore.  This was not acceptable.  So — this prompted a “fun” weekend DIY project to replace the lenses using parts sourced online.  If there is a will, there is a way!  I couldn’t stand the dingy headlights any longer and didn’t want to spend the money on brand new complete units unless all other options were exhausted. 

Special Note: This is a non-trivial project.  Take your time and be careful if you decide to proceed.  Once all parts/tools/supplies were on-hand, this project was completed in a weekend.  Disclaimer: I am not a certified mechanic just a weekend enthusiast.  I put this post together to hopefully help someone more fully understand what they are getting into before undertaking this project and to share what I have learned.  Use this information at your own risk.  Specific brands of tools, parts, places to buy things are for reference only – you should make your own assessment and choose what works best for you.  I hope you find it helpful. 

Result: In my case, the cost of replacing both headlight lenses was a weekend of my time plus about $333, excluding tools (most of which I already owned).  At the dealer, it would have cost many times that amount.  The headlights look brand new now and have a great seal against the elements.

Pre-procedure (approximately two weeks to procure parts)

1. Study the entire process (including the referenced videos), parts and tools recommended and make sure you feel comfortable doing this.  It is not for the faint of heart.  You can also use this process if you want to add some fancy aftermarket light modifications or replace a failed internal component to a headlight (other than bulbs).  
2. Order parts and acquire any tools/supplies that you don’t already have (or borrow from a neighbor).
3. Have everything you need available before starting.  The car will not be driveable while disassembled.
4. There was no need to prepare for vehicle computer work as there were not any electrical parts being replaced (in my case) – just the plastic lenses, not monitored by the technology nannies.

Disassembly / removal of headlights (5 hours)

Remove front bumper and the headlight assemblies –  No need to reinvent the wheel – see the video https://www.youtube.com/watch?v=He_AFkS3b44 by Homerraas.  Additional comments regarding the four T30 screws that need to be removed: I removed the wheel well covers in both wheels.  Then, with the steering wheel fully turned one way or the other (depending on which light you are working on), the hardest “hidden” T30 screw can barely be seen.  The easiest way to find it is to follow the plastic brace towards the center of the car from the T30 screw closest to the fender.  Many thanks to Homerraas on youtube.com for putting this video together!  Just to be safe, be sure to set your lights to the off “0” position until ready to test near the end.

Headlight Lens Replacement Procedure (6 hours per light excluding overnight drying time)

1. Lens removal preparation – remove the lens gasket and four screws securing the lens to the housing (save for later).  The gasket is snuggly clipped on to the light housing; un-clip and work it off.  There is a separate piece of plastic (not sure what it is called) that unclips in three places and slides off.  There is also a metal clip about three inches long that unclips then slides out.
2. Lens removal – after viewing many videos on baking the lens to remove intact, I tried it in the oven, first at 250 degrees F and ultimately worked up to 350 degrees F for several tries at 5-10 minute intervals.  After 4 hours fooling around with the oven and picking out Permaseal (or whatever the adhesive), I abandoned this approach (excluded from the 6 hours per light estimate).  Instead, I decided to get more medieval and to cut the lens off (carefully!).  The following video outlines the basic procedure that worked for me to cut out the lens and pick out the Permaseal: https://www.youtube.com/watch?v=W5VC3xDYw5o by Headlightheartsurgeon.  Modifications to this approach: I used a Heat Gun instead of the oven and did not remove the innards of the light instead opting to put a small towel over the lights/parts while gradually working out the remaining lens from the channel.  In order to separate the cut lens from the assembly, it is necessary to remove the screws on the small light on the outside of the assembly (turn signal area) and pull it out– then the assembly slides apart easily.  Be careful to not touch any internal components of the light (or assembly inside of the lens) with your hands/fingers – recommend getting a box of surgical gloves to use throughout the process to avoid fingerprints.  Many thanks, Headlightheartsurgeon for the excellent video!
3. From the cut lens, carefully remove the screws and reflector assembly that is attached to the inside of the lens.  Just be gentle and jiggle it around until it comes out. 
4. Done as part of step 1, here a video on removing the Permaseal which will give you some pointers: https://www.youtube.com/watch?v=9n3aVS_B9pk by Retrofitlab (many thanks!).  For me, a utility knife, flat head screwdrivers of various sizes, and a dental pick (like used to scrape plaque off your teeth) to be the most help.  I did this “cold” without further heating with the goal of removing 90%+ of the old sealant.  Note: the sealant may not actually be Permaseal, I really don’t know but it was tedious work to get out of the channel.
5. Clean out all the debris particles when complete – blow out the light fixture with compressed air.
6. Using surgical gloves and being careful not to smudge anything or the inside of the new lens with your fingers (clean inside of the lens with Windex, if necessary, beforehand), install the pieces removed from the cut-out lens from step 2 to the insides of the new lenses.  This took me probably 15 min per lens to gently finagle the parts into place (on the tabs and aligning the screw holes).  It is not obvious how to do it and difficult to explain, but they do fit perfectly – so be patient and work through it gently.  Once assembled, store the lens open-side down to prevent dust, etc. until ready to assemble. 
7. Sealing the headlight – used Morimoto Retrorubber.  For some pointers on how to use it, here is a video: https://www.youtube.com/watch?v=duFXYRt_nD0 (Thanks TheRetrofitsource Inc!).  Use another pair of disposable gloves for this and if you get any of the material on your gloves, put on a new pair.  Before starting to push the sealer material in the lens channel, be sure to dry-fit the pieces so you get a feel for how they go together before using the Retrorubber.  Once the Retrorubber was molded into the channels, I used the heat gun to make the material more pliable before connecting the lens to the housing.  Right before connecting the lens to the housing (remember the sidelight needs loosened or removed for it to slide together easily), use compressed air to blow any dust or other containments out of both pieces – assembly and lens.  Morimoto recommends using the oven at 250 or 265 degrees for several minutes after fitting the pieces together.  I used the heat gun for the entire process and tightened the four screws a little at a time connecting the lens to the housing to compress the material.  Once the fit was tight, I used clamps (three per light) to further hold the lens to the housing.  I could not find any specific guidance on how long to allow the Retrorubber to cure but I left the lenses clamped overnight to be safe.  The next morning, the clamps came off and excess/overflow Retrorubber material was trimmed off with a utilty knife.
8. Reinstall the headlight gasket (slide and clip-on, the reverse of the removal procedure) on each light being refurbished.  Don’t forget the extra three clip part and metal clip that slides on the outside of the gasket (bottom of light).  In my particular case, I replaced the headlight gaskets on both lights because they were somewhat weathered-looking (although fully functional).  The part numbers are included in the part list.  If you decide to do this step, be sure to give your vendor the VIN number to check for the perfect fit.

Mount the Refurbished Headlights / Reassemble Bumper (3 hours)

1. Test – set the headlights in position and plug in the connectors on the back.  Then, turn on the ignition and test the lights.  Big sigh of relief when they worked!
2. Mount headlights in the reverse order of the disassembly procedure.  The back “hidden” screw is the most challenging part.  A tip: I put a small dab of trimmed but sticky Retrofit rubber in the T30 head which was plenty strong to hold it on the tip of the socket while navigating it into position.  Use the dust/dirt/wear pattern on the upper mounting screws (the two accessible from under the hold) to approximate where they should be tightened.  While doing this, check trim alignment and adjust if needed both on the fender and front grill.  Don’t forget to reattach any connectors that you detached i.e. cameras, night vision, etc. during the process.  Reinstall wheel liners and lastly, the screws directly under the bumper connecting to the skid plate undercover. 

Finishing Touches (30 minutes)

1. Test everything that was disconnected i.e. cameras, lights, turn signals, night sight camera, parking sensors, if applicable.
2. Align headlights – there are many youtube videos on this subject.  My procedure – at night, pull up close to the wall (6 inches is fine) – check level of alignment between two lights – mark with a piece of tape or something at brightest point.  Then, pull straight back to about 25 feet from the lights to the wall.  Adjust the main part of the beam on both lights to be just below side mirror height on an average car.  To adjust: on the 2013 BMW 750li (most other models are similar), under the hood on the left and right sides of the car over the headlight cavity, you’ll notice a half-dollar size circle with a + in the center.  Using a small coin or screwdriver, twist and this comes out.  Using a long Phillips head screwdriver, insert into the white adjustment knob and turn to left/right to lower/raise beam.  Do this on both sides while the car is running (or ignition/lights on) to align.  Replace plastic cover inserts and turn to secure.  Then, test drive and tweak afterwards as necessary.  You are adjusting the low beam – the high beam will follow the low beam adjustment.  On this model, only height adjustments are supported.  The idea in this method (far from an exact science) is to keep from blinding the car in front of you in traffic in their side view mirrors.

Parts needed:

1. Replacement lenses – while there are many places online that sell the lenses, I purchased mine from http://www.headlight-headlamp.com.  In advance of purchase, I emailed them pictures of the car’s headlights and VIN so they could make sure they were sending the right parts.  Cost was $230 delivered for both lenses (via PayPal).  It took about two weeks for delivery from China.  The parts fit perfectly.
2. Gaskets for around the lens – BMW part numbers 63-11-7-225-237 and 63-11-7-225-238 (for left and right headlights).  Cost was $81 delivered from https://www.bmwpartswholesale.com.  It took about a week for delivery. Replacing these gaskets was completely optional from a functional perspective i.e. the original gaskets were fine and could have been reused.  That being said, they were somewhat weathered in appearance.
3. Morimoto RetroRubber OEM Grade Butyl Headlight Sealant (black).  Cost was $22 from www.amazon.com prime.  This is the product I used to seal the new lenses to the headlight.

Tools/supplies used:

1. BeeSure BE1118 Nitrile Powder Free Exam Gloves, Large (Pack of 100).  The cost was $6 from https://www.amazon.com  prime. 
2. You need some clamps such as Irwin quick grip one-handed mini clamps of various sizes 6” to 18” or so for the purpose of clamping the headlight lens to the base while the Retrorubber is setting-up. 
3. Metric sockets including T25, T30 (and smaller for some headlight screws) as well as standard metric bolt sizes (5, 6, 7, 8, etc.).  I used both ¼” and 3/8” rachets both with and without 3” extensions, depending on the location of the screws.
4. Variety of flat head screwdrivers (small to large) for prying the lens out as well as cleaning Permabond or whatever nasty cement used to factory seal the OEM headlights.
5. Heat gun – Wagner Furno 500 – available at Home Depot for $41.  Any heat gun can probably work but this one has several different heat settings.  I used up to 50% of the Furno 500 max temperature.  Note: I initially tried the oven process starting with 250 degrees F up to 350 degrees F, repeated baking cycles for 5-10 min without success, for hours before abandoning the oven approach.
6. Metal Dental Pic – picked mine up at Walgreens and used it to dig the Permabond or whatever nasty glue it was out of the channels in the harder to reach places.  These are very similar to the tools used at the dentist to scrape plaque off your teeth at cleanings.
7. Utility knife with sharp blades – used to help cut and loosen Permabond glue as well as for trimming of excess RetroRubber sealant after it had cooled/set up. 
8. Air compressor with “blower nozzle” – used to blow out dust and debris out of light housings as well as the lenses before final installation.   You may be able to use another source of compressed air but a compressor is really the best option. 
9. Rigid Job Max multi-tool – used to cut the lens carefully.  They are available at Home Depot for around $100. A small circular tool such as a Dremel would work fine as well.
10. Scissors – to cut the RetroRubber sealant after completing pushing it in the channel around the light housing.  Alternatively, a utility knife can be used.
11. Tweezers and forceps are also helpful in picking out the Permabond glue.
12. Large pliers – I actually used large electricians’ pliers the most to pull out the old lens piece by piece.
13. Tin snips – to make the initial cut of the remains of the old lens glued in the channel after prying out (enough to get the snips under to cut).  Then, use the pliers to pull it out working your way around the fixture with the heat gun to loosen the Permabond’s grip a little at a time.  Use a smallish flat head screw driver to break the seal on both sides of the channel; at times, you’ll have to work diagonally with the screw driver as you go to help loosen the seal along with heat.
14. Stable work area with a vice or integrated clamps to hold the light firmly in place while working on it.  I used a Worx Pegasus Multi-function Work Table with Quick Clamps and Holding Pegs, available for $100 at https://www.amazon.com or at Home Depot.
15. Shop Vac – used to sweep up debris especially resulting from the initial cutting of the lens as well as many pieces of Permabond while and after cleaning them out of the light housing channel.
16. Flashlight – to find the “hidden” T30 screw behind the wheel well on the backside of the headlight (both sides).

Feel free to post any comments or references to alternative procedures that are better.  Good Luck!