amstel78

Seems like my IC pump is kaput. While the car has decent power (it still accelerates like a raped ape on the highway), that can most likely be attributed to the fact that ambient air temperatures in my locale has been very low; 20-40F on average. I'm sure this will change once summer arrives unless I fix this issue.

To test, I took the car out for a morning drive with my OBDII computer plugged in. This morning's ambient temperature was around 25F. Cruising on the highway at 70 mph, IATs read between 89-103F. After a short burst of full pedal madness, IATs climbed to 125-135F and gradually (very slowly) came back down to the previous readings. If the IC pump was working, I'd expect the IATs to be in the neighborhood of 20-30F above ambient and return to normal much faster, which was not the case..

The IC system definitely has water/coolant in it. I don't know if it was ever serviced by the PO, so I can't rule out a massive air pocket messing with my numbers. However, the car has 55k miles on it, so I doubt anything was done. That leaves me to replacing the IC pump and attempting to bleed it myself.

Does anyone know the correct part # for the pump on my S65? Plutoe, if you're reading this, my vin is WDBNG79J56A477014.

Thanks!

Edit: my parts guy gave me this Bosch part number: 0005000386

Welwynnick

No need for chassis number, there's only one type of pump - it's the Bosch intercooler pump. That's it. It's fitted to lots of cars with charge coolers.

The MB part number is 000 500 03 86.

The Bosch part number is 0392 022 010.

There are earlier versions of the Bosch pump that end 002 or 003, but the 010 is best. Any of them will fit and work.

It's probably best to test the pump first, though. You can test it by jumping the relay - its the middle of three relays on the right hand side of the engine compartment partition.

Nick

amstel78

Thanks Nick. I bought a replacement pump just a minute ago from FCP Euro fort $137 (includes 1 gallon of MB anti-freeze as part of the sale). I confirm that the pump has Bosch part # 0-392-022-010 which if I read correctly is the latest Bosch pump with better flow. Hopefully this will alleviate the high IATs described in my initial post.

By the way, some people say the system will burp itself after changing the pump. Others meanwhile state that the system has to be fully bled. I'd rather avoid taking the car to a stealership if possible. Is there a DIY method of bleeding/burping the system that's at least mostly effective?

pumpedTSI

It "should" bleed itself.......clamp the lines on in/out side of the old one before removal (pair of needle nose vice grips with some rubber hose slipped over the jaws) to avoid losing too much coolant.....remove and replace.....no big deal.

Welwynnick

Sorry, it won't bleed itself. It's a terrible cooling system. There's an air lock in the return pipe from the IC's to the HE (with it's own bleed point) and the inlet and outlet of the HE are both low down (unlike any radiator). The intercoolers themselves are just full of air locks, and to make things worse, the two Schrader valves on top are fill valves, to let coolant in, rather than bleed valves, which let air out. Oh, and there's no proper header tank. Nobody would ever make a cooling system like that again.

Nick

E42AMG???

If you clamp the lines off you will not have to worry about bleeding the system.

cmpcpro

I hear so much information I don't know what to believe. I can tell you this: I just replaced mine with the updated Bosch you just ordered and my technician friend who owns his own Mercedes shop said if just replacing the pump it will bleed itself.. if you notice on the two cooling lines up top one has a rubber hose going to the overflow tank so clearly it will bleed itself. However, where it gets shady for you.. I just read I believe lastnight on either this or Benzworld that the 600/65 system won't bleed itself.. not sure if it's correct but searching for other stuff that came across my screen.

Welwynnick

What two cooling lines - are you talking about the engine cooling system? That has one bleed line from the thermostat housing, and one bleed line from the top of the engine radiator outlet tank, and they both go to the engine cooling system header tank. That's how proper cooling systems always work, and that's exactly what the IC cooling system DOESN'T have. It's an unforgivable mistake by Mercedes IMHO, and one that they appear to acknowledge by specifying a vacuum filling system.

Nick

amstel78

Nick, do you think the technique described in this thread would be somewhat sufficient for removing most of the air in the system?

Edited to add: these look like they would work for bleeding the system. What do you guys think?

These chucks look even better:
P.S. I just re-read your first post to me. You said to test the pump first by jumping the relay. I assume it's a three or four pronged relay. As I've never done this before, excuse the noobish question, but how do I jump the relay? I'm assuming pull the relay out, and stick a piece of wire into the sockets that correlate with the relay schematic for off/on?

amstel78

Yes, but what about the air introduced by replacing the pump. The replacement pump's impeller housing won't be filled with liquid when doing the swap, so the moment you connect everything and the pump kicks on, won't there be a rather large air bubble now in the system?

jhandy1

i could hear fluid flow into the pump as soon as i unclamped the lines. then started the car and watched in the fill hole and you could see the fluid lower thereby expelling the air bubble. after driving around a little. i would fill. the coolant expands when hot and will flow out the drain nipple on the back of the filler neck.
don't make it harder than it is.

amstel78

Thanks. I'll replace the pump first and take it from there. If IAT's come down significantly to where they're no more than 30F above ambient, I think that's sufficient.

ItalianJoe1

The system must be bled, if there's air in it it will not be 100%. I tend to run the pump (jump the relay, the front and rear of the 4 terminals), with the filler cap off and filled to the top (cap the overflow nipple and fill it right up), it will push most of the air out.

If the system is way down, you will need to pull the valves out of the bleeder ports and let them flow into the neck, best way is with a large radiator filler funnel so there's room. Run the pump for a minute, then stop and let the bubbles settle. Do it again, until only clean, clear coolant comes out with no bubbles at all.

Or, get a dealer to bleed it with the vacuum filler system.

cmpcpro

Im talking about the S55. The two hard lines going to the supercharger or intake.. one of them on the E55 has a cap where you bleed the system but on the S there is a small hose there going to the coolant tank. That line is obviously going to allow the air to flow into the tank.

amstel78

On the S65, is the IC pump relay "W" on the chart attached? Also, cannot find the pump fuse on the chart. Can anyone shed some light?

Welwynnick

The technique in that thread is well know and well used by forum members, but I'm not entirely convinced it's effective. The V12TT IC system is very difficult to bleed, and very sensitive to air. As soon as you get any in the system, the pump causes the coolant to foam, which both slows circulation a lot, and reduces heat capacity.

When I first got my TT, I spent a whole week just fitting and testing different pumps and heat exchangers, trying to measure and optimise flow. I was difficult even getting a very modest flow figure, like 3 gpm. The tiniest bit of air killed the flow, and I ended up spending all my time bleeding instead of modding. It was incredibly frustrating.

Using the Schrader fill valve ports to let air out is a good idea, but since you need to remove the valves, it's difficult to bleed and get the valves back in, without letting any air back in. Using Schrader valve adapters is a good way to do it, but you have to use AC-size adapters, not tire adapters. You need a 7/16 female adapter to do the job, which you can get in a "refrigeration adapter set" on Amazon or ebay:





The bottom left hand adapter is a 7/16 male to 7/16 female, and that's the only useful one for the IC ports.
Nick

amstel78

Noted Nick.

Can you confirm that it's relay W? What about the fuse? Can't seem to find its location on the fuse diagram.

Welwynnick

Yes, it's relay W.

You jumper the front and aft terminals.

IIRC you don't need the ignition on, which is a great help.

Can't remember the fuse, sorry.

Nick

Welwynnick

Sorry, my bad, the V8 system is quite different. It shares the engine coolant reservoir, and bleeds to that.

Nick

amstel78

Thanks for confirming that relay number. If it's not too much trouble, have a look at the fuse chart I uploaded in post #15. I've been scanning it up and down, and can't find any fuse remotely related to the IC pump. I only see a listing for the relay. Strange.

Welwynnick

Me too.

amstel78

Very strange. Hard to believe that our cars wouldn't have a fuse for this pump...

ItalianJoe1

Fuse #90, a 10A, in that box. According to my starwiring diagram anyway.

It's on the outlet side of the relay, as per the diagram, which makes it very odd indeed. I didn't drive my CL to work today or i'd go look.

amstel78

Thanks Joe. Weird that it's not mentioned on this list, but the block diagram certainly shows a 10A fuse being present.

ItalianJoe1

Those cars are odd, there were very few made and the majority of the diagrams are related to the non-v12 cars. Even the pictures in the locator of the program I use (MB factory stuff) shows a non-turbo car when it's pointing to the fuse box. Which clearly doesn't have an intercooler pump, but that's what it is.

They probably never updated the fuse diagrams in some sources.

FWIW, there are always 3-4 ways I can access this type of info, and rarely do they all agree perfectly with each other. Some info is just wrong, and you can't trust every single piece you find.

If you guys need tech info though, I can access anything there is and will gladly share if I can find it.