S65 radiator replacement

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Sep 7, 2016 | 06:35 PM
  #1  
Hey guys
Has anyone out there replaced the radiator in a W221 S65? I plan on doing it but my only question is how do I know how much trans fluid to put back in?
Any help would be greatly appreciated.
Johan
Reply 0
Sep 8, 2016 | 07:58 AM
  #2  
If you disconnect the TOP transmission oil connection first, that will allow air into the cooling circuit, so all the oil can drain into the sump.

Therefore when you disconnect the LOWER oil connection, you should only lose a drop or two.

Big hint though - before you put the new radiator in, make sure your existing pipe fittings fit the new radiator!

Nick
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Sep 8, 2016 | 03:21 PM
  #3  
Quote: If you disconnect the TOP transmission oil connection first, that will allow air into the cooling circuit, so all the oil can drain into the sump.

Therefore when you disconnect the LOWER oil connection, you should only lose a drop or two.

Big hint though - before you put the new radiator in, make sure your existing pipe fittings fit the new radiator!

Nick
Sounds like you have been there before Nick. I ordered a new Nissen OEM so I hope it fits. Thanks for the heads up.
Johan
Reply 0
Sep 18, 2016 | 07:33 PM
  #4  
It is almost out but it just won't do it! Any tips or advice how to get this radiator out of this thing? There is a clip I can't get loose on the passenger that is holding the radiator to the condenser. My only other idea is that I need to remove the lower radiator bracket as well so it can drop down a little then get pulled out.
Anyone have any advice?
Johan
Reply 0
Sep 19, 2016 | 08:34 AM
  #5  
Getting the radiator brackets in and out is awkward and best avoided if possible.

The key to working on the radiator is good light.

I think the condenser is mounted with a plastic frame on the W221?

Nick
Reply 0
Sep 23, 2016 | 08:57 AM
  #6  
I am not going to lie, that really sucked!
That being said the new radiator is in and so far working great. The hardest part of the entire job besides only having one jack and laying on the ground was I had no idea how to do it really. There is clearly a specific order in which it all must happen or it seems near impossible to do otherwise. Not a lot of spare space to work with in there.
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Sep 19, 2018 | 07:47 PM
  #7  
I'm faced with the same task. Seam at driver's side of radiator cracked for a leak as I've seen others complain of.

Any pointers for how to wrestle the dumb thing out of there?

Fan is out. Hoses off. Does the whole stack have to come out or is there a clever work-around that I have missed?

Thanks!
Reply 0
Sep 20, 2018 | 07:14 AM
  #8  
Removing the radiator is surprisingly difficult. Here's how I did it:

Before doing anything, inspect the new radiator and make sure it’s to spec; this is really important.
  • Make sure the outside diameter of the hose receptacle is 41.0 to 41.5 mm.
  • Make sure you have threaded receptacles for the fan cowl, IC HE, IC pump, AC HE and AC pipe fittings.
  • When you remove the old radiator, some of those fittings may be rusted up – test them first, and figure out what you’re going to do.
  • There are rubber & plastic mouldings all around the radiator to control airflow, and they take time to remove & refit.
  • Establish whether your header tank fills to the RH header tank, or the bottom hose.
  • The new radiator may have a ¾” filler hose receptacle that may need to be blocked off – which can make fitting more difficult.
Get yourself some good lights, and get to work….
  • Lift the front end of the car onto stands and remove the top and bottom covers.
  • Loosen the header tank cap and drain the cooling system. This takes a while.
  • Remove the thermostat/top hose housing and disconnect all the hoses (expect spills).
  • Disconnect the electric fan.
  • Remove the small clips that hold the top of the fan cowl to the radiator flange.
  • Remove the two clips that hold the bottom of the fan cowl to the radiator flange.
  • Undo the two transmission oil cooler pipes, catch a bit of oil, and cover the pipe ends.
  • Undo the two nuts at the top corners of the fan cowl.
  • Pull the fan assy up an inch, tilt it back and pull it out upwards (pushing the IC pipes out of the way).
  • From underneath, undo the IC pump and its bracket from the radiator.
  • Still underneath, remove the bolt that holds the aircon pipes bracket to the radiator.
  • Unbolt the top L&R of the aircon condenser from the radiator.
  • Unbolt the IC heat exchanger from the radiator, and support it.
  • Undo the plastic clamps that hold the top of the radiator.
  • Push the top of the radiator back and remove the bleed pipe.
  • Remove the plastic brackets that are clipped half-way up each side of the radiator.
  • Lift the radiator out.
Lifting the radiator out is unsurprisingly more difficult than it sounds, as it’s a tight fit width-wise between the chassis rails. On my car there were three steering and suspension oil coolant pipes that squeeze through an aperture alongside the radiator. The aperture is sealed-up with a triangular rubber grommet, which best pulled forwards out of the way of the radiator. The pipes then need to be manipulated so they’re flat against the chassis rail, and give as much room for the radiator as possible.

Now is the time to replace the anti-freeze, the thermostat, the thermostat housing o-ring, the hose connector o-rings, and the hoses and aux drive belt if you feel like it.

Refitting is the reverse of removal, but:
  • Check that the top hose assy fits both radiator receptacles before fitting the radiator (ask me why).
  • Tape sheets of corrugated card to the front and rear facesof the new radiator, otherwise you’ll make a horrible mess during fitting.
  • Make sure the aircon condenser is in about the right position before you push the new radiator forwards into position.
  • Make sure all the small hoses and cables are tied away from the moving parts, like the ancillaries and the aux belt.
  • The cooling system bleeds itself, but only when the engine is fully warmed-up, and you need patience.
If you’re prepared, it should take about a day.
Reply 3

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Sep 20, 2018 | 08:30 AM
  #9  
Thanks Nick, nice write up on this mean job!
I had no directions on how to do the job other than old school determination and hard work. The removal of the old radiator was the hardest part from what I can remember.
Good luck.
Johan
Reply 0
Sep 23, 2018 | 03:45 PM
  #10  
Love the BB software that informs me that I've 'timed out' after typing out a reply. Ahhhh

My car is a 2008 221 Chassis S-65. A few pointers to add to above post by Nick.

Biggest pain in doing the job was dealing with the plastic that guides air on each side. Snip bottom of each of them where it goes around a hose for much easier installation.

Charge cooling HE, A/C condenser, P/S cooler (or is that ABC?) are one stack that slide into radiator at the bottom and click in place on a pair of clips 2/3 up the radiator. One 6mm bolt at driver's side down low on radiator core for the pair of A/C lines. Two bolts per side release the engine oil cooler from the plastic hangers that attach to the radiator. Then that pair of hangers come right off of the radiator. No need to evacuate and recharge A/C.

I pulled the core support to do this. Should I get to do this task again it will stay in the car.

My first time doing it... Eight hours. Next time will be four. If you are conscientious and not a savage it comes apart easily enough.
Reply 0
Mar 7, 2020 | 10:55 AM
  #11  
about to tackle my 2008 S63. Thanks for the tips
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