Do W203's have an aux water pump?

[robparker]

If so... where is it?! Got an early W203 C180 here with no hot air in the cabin, all other models I know of have an auxiliary water pump but I cant find it on this, anyone know?

 

[robparker]

Just to half-answer my own question, it seems some of them have the aux pump stuck right on the front of the expansion tank, this one doesn't, so is this relocated, or just removed and circulation relies on the main water pump?

Where the water pipe t's off from the engine and goes off to the bulk head is cold when engine is up to temp, its slightly warm where it comes out from the bulk head and back into the engine, making me think its not circulating, either due to a pump or blockage.

 

[turbopete]

doesnt it just go to the heater matrix when it goes to the bulkhead? cant say i ever needed to take much notice with my old 203

 

[robparker]

Yes I think so, but there is usually a pump in that water line between the engine water pump, expansion tank and the bulkhead, not on this one though, that I can see

 

[turbopete]

i wonder if its worth disconnecting the hoses and testing the heater matrix with a hosepipe?

 

[M80]

Never had to work on this but,
aren't there solenoids in line. I seem to remember talk of duo valves that stick and can be freed, if lucky, by manipulating the controls.

 

[turbopete]

would a duovalve stop the throughflow from the heater matrix though? ive never had to work on one either. usually hot air comes from the heater matrix from air flowing through the matrix. cold air from the outside air or via coolers now (in the case of aircon)

 

[robparker]

I believe there is no duo valve on the 203, but instead air is either directed through or around the matrix via flaps depending on heat selected.

 

[turbopete]

i have to say that flushing the heater matrix with a hosepipe would be my first point of investigation on this one.

 

[Cole@MBS]

i have to say that flushing the heater matrix with a hosepipe would be my first point of investigation on this one.

Most common prob with a 203 is blocked matrix..........

 

[LostKiwi]

i have to say that flushing the heater matrix with a hosepipe would be my first point of investigation on this one.

That's where I'd start too. I've never heard of any car having an auxiliary water pump for the heater unless it was equipped with a webasto/eberspacher auxiliary heater.

 

[EmilysDad]

..... I've never heard of any car having an auxiliary water pump for the heater unless it was equipped with a webasto/eberspacher auxiliary heater.

My R Class does .... as other i believe other Mercs have to allow you to use the heater when parked up without the engine running. Some Omegas had the same for the same reason.

 

[LostKiwi]

Ah good point. I'll have to check the r129 as it has the 'Rest' function as well.

 

[Arzaam]

i have a c180 w203 same as yours,are you talking about the thing in front of the expansion tank and the silver thing in front of it or does your car have a empty space there?

mine does have a rest button in the climate control panel where it blows hot air about for 15min or so once the engine is off, i dont think there is a duo valve but flaps as dealer mentioned this in a discussion once and flaps can sometimes get stuck. there is a reset procedure by pressing some buttons i think it was in some forum post here or elsewhere.

my heater works well nor leaks, i did not service the heater matrix nor was it ever done in the service history though we dont have harsh winters over here.

mine also has a heated washer system maybe it relates to that as that also i believe take heat from a pipe running next to the windscreen wash bottle or something.

dont mind the dirty engine bay

DSC02397 by Arzaam Bhatti, on Flickr

 

[robparker]

i have a c180 w203 same as yours,are you talking about the thing in front of the expansion tank and the silver thing in front of it or does your car have a empty space there?

mine does have a rest button in the climate control panel where it blows hot air about for 15min or so once the engine is off, i dont think there is a duo valve but flaps as dealer mentioned this in a discussion once and flaps can sometimes get stuck. there is a reset procedure by pressing some buttons i think it was in some forum post here or elsewhere.

my heater works well nor leaks, i did not service the heater matrix nor was it ever done in the service history though we dont have harsh winters over here.

mine also has a heated washer system maybe it relates to that as that also i believe take heat from a pipe running next to the windscreen wash bottle or something.

dont mind the dirty engine bay

DSC02397 by Arzaam Bhatti, on Flickr

Yes this is the pump, but this car doesnt have anything there.
Once I get the car back (its a family members) I will do a matrix flush to begin with to see how that helps. A flap reset has already been done.

 

[television]

If no rest function on the car then no pump. Only fitted with the better Air con system.

 

[Donald McPherson]

I'm still having problems with my heat. I also don't have the auxiliary pump. I have flushed the matrix out by disconectingthe hose beside the expansion tank, stuck the garden hose in there (good fit) and flushed. Wound a few rolls of duct tape on garden hose and forced it into the plastic end to flush opposite way. I even tried clamping the top radiator hose one time. The heater worked fine for a few weeks then looses heat again. I'm wondering if I have a pinhole leak somewhere that is causing an airlock in the matrix. PS I have not replaced the antifreeze yet untile I get this solved or winter aproaches so need to figure this out. Would the pump solve my problems?