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Has anyone replaced the coolant pump on an M157 engine?
I'm looking to replace the coolant pump myself but I keep getting conflicting information. Some say I don't need to replace the Thermostat, some say I do.
I was hoping someone can share some light into the replacement of the coolant pump as I know they tend to leak after a while
#9 is the pump and #6 is the thermostat, you don't have to replace both but it would be a good measure to do both at once since it wont be easy getting to them.
#9 is the pump and #6 is the thermostat, you don't have to replace both but it would be a good measure to do both at once since it wont be easy getting to them.
Thanks for your reply do you know anything about having to replace the coolant pipes for the Turbos?
I don't have direct experience but its not too hard, just need to clear the way to the lines. They usually start going at higher mileage, check this thread.
I had my water pump fail at a track day. Had a local shop replace it, which took them a month because of parts.
Basically, they removed everything, in the process, the coolant lines for the turbos failed too, because in Mercedes infinite wisdom, used plastic fittings.
So, just plan to replace the pump, thermostat, and turbo coolant lines all at once.
I replaced my thermostat a few weeks back and have been meaning to post a DIY. While you don't technically need to replace the thermostat, just know there is the possibility of it coming apart when you remove it from the water pump. There are some plastic clips on the water pump side that snapped when I removed mine and would have made it unusable. If you decide not to replace the T-stat, just be gentle when removing it from the pump housing.
I replaced my thermostat a few weeks back and have been meaning to post a DIY. While you don't technically need to replace the thermostat, just know there is the possibility of it coming apart when you remove it from the water pump. There are some plastic clips on the water pump side that snapped when I removed mine and would have made it unusable. If you decide not to replace the T-stat, just be gentle when removing it from the pump housing.
I'm surprised how no one has posted a DIY on the M157 water pump knowing how common they are to give way at high mileage. I'm looking to replace both the water pump and thermostat and the coolant lines to the turbo and would love to get a DIY guide on how to do it
I'm surprised how no one has posted a DIY on the M157 water pump knowing how common they are to give way at high mileage.
I'm wondering what is defined as "high mileage." At what mileage or age are people typically experiencing water pump failures? I have a 2015 M157 and am looking to replace turbo coolant pipes for dependability, and am considering doing water pump at the same time if they typically fail in the 8 year/80k mile range.
The water pump can easily tell its on its way out by looking at the pulley, it starts to walk itself towards the front of the car, and you can tell the pulley gets further away from the belt center.
I'm wondering what is defined as "high mileage." At what mileage or age are people typically experiencing water pump failures? I have a 2015 M157 and am looking to replace turbo coolant pipes for dependability, and am considering doing water pump at the same time if they typically fail in the 8 year/80k mile range.
if your doing the coolant lines, you may as well change the thermostat and water pump as a preventative maintenance. Not to mention you’d save on labor/time if those parts need replacing
14 E63, 05 E55, 03 Evo 8, 08 F250, 06 R6R, 92 Talon TSI, and instability
Originally Posted by AMGfifty5
if your doing the coolant lines, you may as well change the thermostat and water pump as a preventative maintenance. Not to mention you’d save on labor/time if those parts need replacing
If you're doing the coolant lines, chances are you'll HAVE TO replace the waterpump as the part of the coolant line that goes into the WILL break upon removal.
I'm surprised how no one has posted a DIY on the M157 water pump knowing how common they are to give way at high mileage. I'm looking to replace both the water pump and thermostat and the coolant lines to the turbo and would love to get a DIY guide on how to do it
if your doing the coolant lines, you may as well change the thermostat and water pump as a preventative maintenance. Not to mention you’d save on labor/time if those parts need replacing
Well, I do my own work, so I wouldn't be paying anyone for the labor.
Further, yes, I completely understand this as that's what I'm trying to understand. Do they fail right around the 8 year/80k mile mark, or do they last much longer? If 8 years/80k is close to the limit, replace preventatively. If they typically last much longer, do not replace.
Also, while there may be a one-year warranty on a replacement water pump, those water pumps, even from MB, are remanufactured, not brand new, and the warranty doesn't cover labor to replace it if it fails within the warranty period.
Therefore, I still would like to know when people have actually been experiencing bearing and/or seal failures of their original water pumps. That will tell us a lifespan of the part and we can better plan for "maintenance" better known as a repair.
14 E63, 05 E55, 03 Evo 8, 08 F250, 06 R6R, 92 Talon TSI, and instability
Originally Posted by mweber88
Well, I do my own work, so I wouldn't be paying anyone for the labor. Further, yes, I completely understand this as that's what I'm trying to understand. Do they fail right around the 8 year/80k mile mark, or do they last much longer? If 8 years/80k is close to the limit, replace preventatively. If they typically last much longer, do not replace. Also, while there may be a one-year warranty on a replacement water pump, those water pumps, even from MB, are remanufactured, not brand new, and the warranty doesn't cover labor to replace it if it fails within the warranty period. Therefore, I still would like to know when people have actually been experiencing bearing and/or seal failures of their original water pumps. That will tell us a lifespan of the part and we can better plan for "maintenance" better known as a repair.
The problem you're going to encounter is the turbo coolant lines becoming extremely brittle and breaking/failing prior to the pump itself hitting its useful lifespan. When (not if) that happens, the line that goes into the pump will most likely be seized at the nipple and break inside the pump from having heated and cooled repeatedly. The picture I posted above is the aftermath. Your options at that point are either 1: try to drill that nipple out and pray no plastic/composite shards get into the pump or 2: replace the pump.
Honestly, I wish MB had opted for metal lines with oring gaskets over the composite ones.
The water pump can easily tell its on its way out by looking at the pulley, it starts to walk itself towards the front of the car, and you can tell the pulley gets further away from the belt center.
@5soko How bad would you say this is? I've already ordered the parts but the shop that's going to do the replacement is 20 miles away. Risk it and drive there or just hire a tow truck?
@5soko How bad would you say this is? I've already ordered the parts but the shop that's going to do the replacement is 20 miles away. Risk it and drive there or just hire a tow truck?
Yea, thats just about dead and past due a changing. Sometimes, the inside impeller will start eating into the housing now that it is getting pulled, and start tossing small alum metal into the coolant channel.
Yea, thats just about dead and past due a changing. Sometimes, the inside impeller will start eating into the housing now that it is getting pulled, and start tossing small alum metal into the coolant channel.
@5soko I’m glad I caught it in time before things went completely sideways. What are your thoughts on driving it 20 more miles to the shop for when I replace it? I won’t be driving it anymore until then.
04-26-2020, 12:28 PM
