Aux water pump on my 1991 190E 2.6 has started leaking (Borch APG 12V 0
130 002 070) from the black plastic housing. The pump appears to be still working & I still get full cabin heat etc., but I do get some clicking noises from the passenger side glove box. Also, the leak is not major at this point, just spots on the ground when the car is parked.
Three questions:
Rather than going out and buying a new part (approx. 0-140) or searching the junkyards for a used part, is it possible that this unit can simply be removed and perhaps be repaired with new gaskets, seals etc?
If I do remove the unit for inspection/repair, would I do any damage by temporarily rerouting the hose from the water pump going to the unit directly to the black metal tubing going to the heater core (effectively bypassing the aux water pump altogether) and driving for short distances?
If it is possible to simply repair the unit by replacing gaskets/seals, does anyone know of someplace that stocks the parts the repair?
I'd hate to spend $130 plus on a new unit if it is possible to repair with a few dollars in gasket parts.
This pump helps to bring hot water quicker and more efficiently to heater core. It does not participate in the engine cooling. So, there is no damage to bypass this pump. AFAIK, the whole pump is sold as a unit, no internal part is available (from dealer). I am not sure if generic gasket/seal can be used for repair. I chose replacement a few years ago when this pump was only about $80. Not anymore, thanks to current Euro exchange rate. Note that if the electric portion of this pump fails, it may draw too much current which will burn the push button control (PBC). Therefore, buying new part also gives you this insurance. The clicking sound behind grovebox comes from the switchover valves (which converts electric signals from PBC to full or no vacuum to control motors). The clicking is normal when switching on or off the valve. However, the rapid and continuous clicking when using heat on W201 usually means the potention meter on the blender door is failing so PBC cannot determine the opening angle of this door. Unfortunately it is a many-hour work to replace this sensor which is deep inside dash. Many people choose to live with it. glgxg wrote: Aux water pump on my 1991 190E 2.6 has started leaking (Borch APG 12V 0
130 002 070) from the black plastic housing. The pump appears to be still working & I still get full cabin heat etc., but I do get some clicking noises from the passenger side glove box. Also, the leak is not major at this point, just spots on the ground when the car is parked. Three questions:
1. Rather than going out and buying a new part (approx. $130-140) or searching the junkyards for a used part, is it possible that this unit can simply be removed and perhaps be repaired with new gaskets, seals etc?
2. If I do remove the unit for inspection/repair, would I do any damage by temporarily rerouting the hose from the water pump going to the unit directly to the black metal tubing going to the heater core (effectively bypassing the aux water pump altogether) and driving for short distances?
3. If it is possible to simply repair the unit by replacing gaskets/seals, does anyone know of someplace that stocks the parts the repair? I'd hate to spend $130 plus on a new unit if it is possible to repair with a few dollars in gasket parts.
Just replace it. I got one for 91 dollars locally here in san diego and changed it in 15 minutes. Lol. you really want to fix it? If you are a really cheap bastard, put a piece of pipe in between where the pump was and throw the bad pump away. Zip tie the wires out of the way somewhere they wont short, it will be fine. KH
Interesting comments from someone that tore his dash apart to find a cold solder joint rather than taking his car to the dealer. ;-)
As I said in my first post; the aux water pump is working just fine, it just had a small leak from the black plastic housing. I removed the unit, cleaned it, put in a new rubber gasket, sealed it back up, lok-tightend all of the screws, and re-installed. I've now driven the car for a little over 180 miles in stop & go traffic (w/heater on just to be sure), and haven't lost a drop of coolant since.
Total time to repair: approx 30 min, total cost: $2.60 for 24" of spare heater hose to put in the trunk for by-passing the pump later on -- just in case I'm not as smart as I think I am.
So, call me what you want, but sometimes it pays to be a "really cheap bastard"...
Sometimes I wonder if fixing something the "right way" (to remove & replace with a brand new part) is really necessary -- I suppose time will tell if the unit continues to work properly & w/out leaking in the miles to come, or craps out. But if it does crap out sometime down the road, then I now know enough about what the unit does (and does not do) and can safely bypass the temporarily if necessary until I can replace with a new part.
In my case, it appears that 97K miles of road vibration may have just loosened the casing screws and allowed the unit to leak from the plastic propeller housing. The two screws at the base of the metal housing were loose, allowing the top portion of the unit to move just slightly. The screws at the top of the black plastic housing for the pump propeller (the coolant chamber?) where the hoses connect were slightly loose as well. I only replaced the rubber gasket in the coolant chamber housing as a precaution -- the original wasn't cracked, broken, or dry -- and used one that fit perfectly from a grab bag that I had on hand.
Upon closer inspection of the unit, it seems to me that the unit is nothing more than an afterthought add-on part from MBZ -- it's not even a real pump actually; it's simply a 12V activated type of device that turns a propeller in the unit's fluid chamber to assist in pushing coolant up into the heater core while the car is at idle. I suppose that there is a reason MBZ added the part (perhaps poor engineering on the
190E 2.6 to begin with, customer complaints that the cabin heating wasn't fast enough or staying hot at idle, or a deal with Bosch & MBZ manufacturing), but the whole unit seems to me to be like a gall bladder
-- it's ok to leave it in as long as it's working and not leaking or causing harm, but also ok to cut it out and forget about it if necessary.
For now the $91 - $130 (or $109 per Ron w/German Star -- thanks Ron for the info & link, nice site) can be used elsewhere.
Perhaps now someone with a similar aux water pump leak problem might be inclined to take a closer look at their unit to see if the unit leak can be repaired individually by simply cleaning and tightening the screws/seals on the unit, or if the unit really needs to be replaced outright.
The aux water pump started leaking again after approx 1,000 miles (at
98K). I removed it completely, put in a $3.00 heater hose and forgot about it. 800 miles & a few cold weather snaps later I've still forgotten about it and haven't had a bit of trouble since. Heater, defrost, aircon all work just fine. Engine is running a few degrees cooler also.
Yep -- I live in the San Francisco Bay area and while it doesn't get below freezing here too often, we do ocassionaly get cold snaps. I've also made one trip up to the mountains were it was below freezing and and on one occassion thought that I noticed a very slight (and I do mean very slight) drop in temperature coming from the vents when the car was at idle for more than a few moments -- might have even been my imagination, but then I just kicked up the temp wheel a notch and that worked just fine.
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