bbirdwell

The attached documents are intended to assist novice DIY's to install a PLM heat exchanger on their W211. The documents may apply to other Mercedes models. I'm posting my lessons learned so others don't have to learn it the hard way like I did.

The documents are *not* a step-by-step instruction manual but rather are an explanation of "assumed knowledge". After doing this once, it's easy, but...the first time, it's difficult because the writers assume that one has knowledge that the writer does. And that assumes the parts come with instructions and my parts did not.

I hope these help others. Remember, you need both attachments!

menace2sobriety

Hey this is great, I've just ordered myself a plm heat exchanger and I see this saving me a headache or two

Any front photos of the end result?

Thanks

bbirdwell

No photos yet. The car is still non-operational as I partially disassembled the rear suspension and I am also repairing an air bag leak.
This weekend I reassemble the suspension and verify the air bag leak is repaired. Then I can bleed the air out of the heat exchanger and put an alignment on the car before taking it out on the road again. And...I need to confirm I didn't screw up a sensor about which I forgot when I was wrenching on the suspension....<sigh> Complicated cars that are unforgiving of mistakes.

menace2sobriety

The plastic tags on the bumper that "may" need to be modified/trimmed - what is the reason for this, is this the part that creates the buldge? Or does the heat exchanger hit it creating fitment issues?

Did you upgrade with the bosch 010 pump, were there any other small parts needed that were a must, or parts that generally could have been needed?

Thanks

bbirdwell

When I originally mounted my heat exchanger (HE) without using the thin washers as spacers, the HE was flush against the aluminum frame and the bumper mounting tabs would not fit between the HE and the frame. I discovered this when I attempted to remount the bumper so...investigate issue, remove bumper, and then figure out how to put a gap between the HE and the frame. Went to remount bumper again...I discovered the mounting tabs had vertical reinforcements molded underneath; not particularly large but just enough to prevent the bumper tab from sliding between the slightly lowered HE and the frame. So...off with the bumper again to remove the extra plastic.

It is helpful to have an extra set of hands to press in on the bumper at the mounting tab location while you pull out on the lower lip to thread the 10mm bolt through the tab.

I installed a new Bosch 010 pump but the car already had one mounted. The pump took maybe 5 minutes.

Overall, not difficult and common hand tools suffice.

menace2sobriety

Thanks for your reply,

Tracking shows that my PLM Heat Exchanger and 010 Pump have all arrived today so I will most likely do it this weekend

Overall how much time do you reckon this entire process would take one person, 8 hours?

What tools are absolutely required:

- Socket set
- Axle Stands
- Beers x36

Washers - amount?
Pliers?
Torx set?
Screwdrivers?
File - or Side Cutters?


* I am going to remove the middle grill on the bumper and leave it off, as far as I am aware there are no other E55's in the city - quite possibly the country I live in that have A/M heat exchangers so I want to "show it off", this should also make it a bit easier as well to get to the 2 bolts up in there when refitting correct

Thanks

bbirdwell

3-5 hours if you save the beer for after. 2 days if you start drinking the beer before you start. ;-)

2-4 washers. Only needed on the inside bolts closest to the HE. Two thin and two thick if you can find them. That way you have a choice. 12mm IIRC. Use the thinnest you can get away with.

Removing the front wheels makes it much easier to pull the fender liners.

-10mm, 12mm, 14mm, 16mm hex sockets. (I used both 1/4" & 3/8" drive)
-Same size combination wrenches.
-3", 6", 12" extensions. (Mixed 1/4" and 3/8" drive)
-Water pump pliers.
-Small tack hammer if you need to tap on the terminal strips.
-Either 6 or 7 or 8mm socket to release the two sheet metal screws that hold the terminal strips on. (I forget the size but they're small diameter.)
-Sheet metal shears (aka side-cutters). The plastic is not particularly heavy.
-Small and medium screwdrivers.
-Second set of hands to assist in removing/installing the bumper plus cloth on which to place the bumper.
-3'-4' of clear plastic line of ~3/8"? I.D. (Not sure on this. I had some hose left over from another project.) If loose, clamp it. If tight, stretch it.
-Coarse file for the plastic or a sharp knife or a Dremel tool to grind it off. The plastic of the bumper tab is soft.

If you have a DAS use it to bleed the air out of the system afterward. Be sure to pinch off the hose just below the bleed nipple. Takes about 15 minutes to bleed it that way.

Control Units/Drive/ME/actuations/M44 (charge air cooler circulation pump)

Without a DAS it takes longer but is do-able. I recommend searching as I saw several posts on how to bleed the system. You can do it by applying power directly to the pump before you bolt the bumper back on (while you can still access the pump's connector). If you do so, use the hint above about pinching off the line while routing the nipple's output back to the reservoir while you apply power. You can also bleed it after installing the bumper but I don't recall how Shardul and others did so.

The attached info is NOT for a W211 but the idea is the same. Only the reservoir is on the opposite side.

Best of luck to you.


EDIT: I just realized you're in New Zealand. Must seem kind of crazy the way we mix Metric and SAE sizes! :-)

menace2sobriety

Thanks for all that, worked a treat and didn't have to rush off anywhere mid install because I had everything needed.......especially the washers for the bumper bracket.....that would have screwed me up if i hadn't known about it.

Just finished the install, 3 hours all up, bumper off, install H/E and 010 pump, bumper on, bleed, easy.

Driving good, no leaks, temps sitting around 5-15 degrees celsius lower than before the install, its summer here so around the 30 degree celsius range in ambient temp

MACEDON

Going to be using this write up this weekend thanks Barry!

tw2

Just finished this job. These instructions are very helpful- thank you very much. Some observations and things that helped me:
- Take off the front wheels, not mandatory but it will make the job much quicker.
- I would recommend getting longer bumper bolts before you begin. I am pretty sure the bolts are M10x1.25 and 120mm long from tip to the end of the bolt head. An extra 10-15mm+ would be perfect. I can't see anything they would bind on so if you get much longer bolts it should work fine. I used the stock bolts and the nuts are tight but only 2/3-3/4 on the ends of the bolts.
- Washers- I used four. One on each of the four bolts between the head exchanger and the underneath of the bumper bar. They were 1.3mm thick, 12mm inner diameter and lowered the PLM just enough to give good clearance.
- Cut exactly where shown in the PDF file on the bumper and it will fit fine. Test fit before tightening anything! You may need a couple of goes to get it right.
- More washers- my PLM had quite large holes for the bolts to pass through, presumably so tolerances could be a bit less important. In any case the nuts for the stock bolts almost fit through the large holes on the PLM. The holes were 18-19mm on mine so get some thick washers that will allow them to sit better, ie flat and not digging into one side only as mine is.
- For bleeding I used the same procedure from my intercooler pump replacement https://mbworld.org/forums/w211-amg/...-pictures.html
- I also drained the engine radiator, there is a small tap on the left side at the bottom, this will lower the reservoir so there will be 2 litres less that you need to catch from the intercooler pump/heat exchanger, just place a smalll hose on the tap approx 6-8mm I think. I used the same one as for the bleeding process.
- I will replace the bolts and get washers for the nuts if I ever take the bumper off again but otherwise I can't see anything bad happening in the mean time.
- The lower bumper sits a bit lower in the middle but the plastic under shield still fits in ok.
- Easy time to replace the $7 outside air temperature sensor if you are so inclined. Also a good chance to check tolerance in the ball joints etc and change the rest of the coolant if still original.

MACEDON

I installed mine using the instructions. Thank you!