w203 c270 cdi coolant loss (water pump?)

[mikehiow]

Hi,

Over the last week or so, I've had to top my coolant up three times.

Looking closer today, the subframe under the radiator seems to have puddles of water in it.

I'm guessing the water pump is a suspect, but access looks pretty bad - I can't even see well enough to distinguish the water pump!

Does anyone have a workshop manual for doing the job?

 

[V12]

I changed mine late one night on my driveway by torch light. Was a pretty easy job from memory.

 

[mikehiow]

Well, I think it's almost certainly the pump.

I went back out and started the car and the pulley almost jumped out of the pump! I turned it off very quickly.

I don't know if that's the first time, or it's been doing that for a while, but either way - very lucky!

Could you give me a rough run down of what you did?

Does the slam panel and radiator need to come out?

I suspect this might be a doddle compared to my RS Clio where everything is an inch from the o/s inner wing!

 

[martyz]

edit

 

[mikehiow]

I've just noticed this is in the Interior forum, no idea how that happened? Could someone move it for me, please?

 

[Dec]

Not sure if this is Diesel or Petrol or if there is any difference, see… Pelican Mercedes-Benz Tech Article - Mercedes Water Pump Replacement - C230 / E320 / S320 / ML320 / CLK320 / SLK320

Dec

 

[BlackC55]

It is a much easier job if you remove the radiator but not essential. Just remove the fan and access should be easy.

 

[V12]

Yeah, I can't remember what I removed but definitely didn't get the rad out.
Mine was actually a w209 so although the cars are almost identical mine may have had slightly more room to work with due to the longer nose of the car.
It was a few years ago but I didn't have any special tools, workshop manual or anything. Just straight forward change for me.

The impeller had become so loose in the waterpump that it had started milling through the front timing cover. Luckily it was caught early or that could have been seriously bad news.

 

[mikehiow]

Well, I've ordered the water pump. I guess I'll give it a go tomorrow!

 

[mikehiow]

Can anyone advise whether it is necessary to apply sealant when fitting the pump or whether the gasket on it's own is sufficient?

 

[BlackC55]

You will need sealant. Blue Hylomar is pretty good stuff.

 

[grumpyoldgit]

Cooling fan & Water pump - How to (W203 C270)

Only just seen your post, hope I'm in time to be of help. Sorry about the inconsistency with the sizing of the uploads. Done in a bit of a rush.











Coolant Pump Mounting Bolts (Diesel Engines) M6 Bolts 14 Nm / 10 lb ft - M8 Bolts 20 Nm / 15 lb ft

Haynes Workshop Manual #4780
C-Class Sept 2000 - May 2007

 

[mikehiow]

Lovely. Thank you very much!

 

[mikehiow]

Is sealant definitely necessary?

There was none before...

 

[jaymanek]

yes,,

 

[mikehiow]

Fair enough.

One other thing that has me confused is a 5mm thick rubber gasket included in the box. I can't see any use for it and can't see that there was one there before. Am I right in assuming that I should just discard it?

 

[mikehiow]

Can anyone advise how to bleed? I filled it slowly after putting an initial 3 litres in and running the car. Its been tunning a while and not even broken 60c yet :/

 

[Auto-mobile]

Bin the rubber gasket and use the metal pressed gasket, never needed to use sealant.. Ever, you will need to drive the car to get any sort of temperature out of it, regarding bleeding mercs very very rarely get air locks, fill it till it's full take it for a drive until heat is in the cabin and then adjust the level.

 

[mikehiow]

Thanks, it's all working now.