T1N 647 Engine Water Coolant Pump Replacement

marklg

Well-known member
The job went pretty well all things considered. I did not swing the radiator. I removed headlights, grill, support bar, fan and shroud and had enough room to work without issue. Actually replacing some of the nine hoses was worse than the pump. Did the pump with the manifold attached. Nice not to worry for awhile about hoses, fan, idlers, belt and pump!

One thing I did that I hadn't seen mentioned is that I but a layer of gorilla tape over the top, sharp edge of the radiator. After scraping my forearms up for a bit the light went on and the tape made a big difference during the rest of the work.

Still waiting on the missing hose that I ordered from a different supplier to come in. I also could not get to one of the bolts on the thermostat with the tools I had. So I yet need to get a long handled T27 key wrench.

As always this forum is indispensable for the DIY guys. Feels good to know that it was done right (I hope) while saving some money.

Thanks to all that contributed, wouldn't have done it without the info available here.
I also found that I needed several lengths of the various Torx wrenches. I think I have the same sizes in sockets, short handled wrenches and long handled wrenches. I even use two different lengths of square steel tubing to put on the wrenches for extra leverage.

The water pump is coming up, about 120k miles, so these posts are a lot of help.

I ordered stuff from Million Mile and got exactly what I ordered. Sorry you didn't have the same experience.

Regards,

Mark
 

Vosoba

New member
Quick question here guys, my water pump bolts are a bit rusty. Will I have a problem down the road if I do not replace them this time around?
 

220629

Well-known member
Quick question here guys, my water pump bolts are a bit rusty. Will I have a problem down the road if I do not replace them this time around?
"A bit rusty"...
a picture might help, but they'd need to be very rusty before I would replace them.

I liberally grease most all bolts which I install and sometimes use anti-seize. In doing that I haven't had any problems with fasteners loosening.

I rarely use thread locker. I only use that on critical fasteners which I feel may loosen for one reason or other.

:2cents: vic
 

TDfanman

New member
Many thanks to those who contributed to this thread. I tackled this last week after a couple years of procrastination.

My water pump started dripping from the weep hole shortly after I purchased my 109k mile 2005. However, usually an engine start would reposition the seal enough to stop the drip for a while, sometime it would go months in between dripping. Now I am at 139K and recently it started dripping every day, so I knew there was no more putting this off. Ironically, it stopped dripping as soon as I ordered the parts.

I usually try to minimize disassembly, but this is a case where that is a false economy. It is so easy to remove the bumper, headlights, and grill, and I swung the whole rad, condensor, and fan as a unit about 45 degrees open and had tons of room to work.

I ordered a new Hepu pump and Meyle fan and clutch assy. The Pump came with new metal gaskets for the pump and manifold. One issue I had is that the fan clutch seemed a couple mm thinner than what I took off. As a result, the fan bolt bottomed out, but failed to tighten the clutch to the pump hub. I had to go to Ace and buy a M10 x 1.50 x 40mm allen bolt and that tightened up just fine.

I'm really lazy, so hate to take things apart twice (especially when they are hard to access.) I went ahead and did the thermostat, tensioner, idlers, Radiator hoses, and boost hoses (Since they were drooling oil and every junction, and since a friend of mine had popped a charge pipe on his sprinter). My hope is that I won't do this again for 100K miles and everything will be good. My only regret is that I did not have all the heater hoses, EGR cooler hoses, and fuel hoses on hand to replace them as well.

I took a photo of the belt routing as suggested, but did not look at it :mad:and managed to find a plausible alternate belt routing. After starting it quickly became evident that something was not right. Easy fix to look at the photo and correct.

I also managed to fatigue the ears that hold the charge air temp sensor onto the boost pipe, and one broke and the sensor blew out as soon as I was in boost. Might be a good thing to add to the parts list if you do the job.

I'm enjoying a lack of any drips whatsoever from the van now, and the fan noise is much more prominent that it was before (because the old fan clutch was leaking). My AC seems a little colder also with the increased air flow.

So, Thanks Again and if anyone is putting this off like I was, it is really not that bad of a job.
 

220629

Well-known member
Thanks for the feedback. :thumbup:

...

I usually try to minimize disassembly, but this is a case where that is a false economy. It is so easy to remove the bumper, headlights, and grill, and I swung the whole rad, condensor, and fan as a unit about 45 degrees open and had tons of room to work.

...
The disassembly of itself is not difficult. Anyone with a rusty old Sprinter should be aware that corroded fasteners and parts can cause problems when disturbed.

There is no way that I would disassemble my 2004 NE rust belt Sprinter more than I did to change out the water pump. The corrosion just sets up too many possible pitfalls.

:2cents: vic
 
Hey all! Great info in here. I just got the cooling system kit from Million Mile Sprinter and am about to do the deed tomorrow.

I was checking out the mounting surface on the new Hepu OEM water pump, and it's all shiny and mostly smooth, except for one edge on it that makes me a bit worried. It's obvious to the naked eye, and is just significant enough to catch my fingernail on. Maybe like the ridges on a penny. I'm wondering if that is a concern? I have a metal gasket, should I throw some sealant on there too and hope? Thanks!
 

sikwan

06 Tin Can
It depends on where the edge is and how it is arranged; perpendicular or parallel to the gasket area. There is that option of removing the ridges (smoothing the surface further) or applying a light sealant. Without pictures, it's a hard guess.
 

220629

Well-known member
... It's obvious to the naked eye, and is just significant enough to catch my fingernail on. Maybe like the ridges on a penny. I'm wondering if that is a concern? I have a metal gasket, should I throw some sealant on there too and hope? Thanks!
If the ridges are raised it can be carefully touched up with a mill file as long as you keep everything flat and don't remove too much stock. A safer method would be to lay a full sheet of 220 or maybe 180 grit on a very flat surface and smooth the entire gasket mating face.

A thin application shouldn't hurt anything and may help. I would use some Permatex #2 non-hardening sealant that I have on hand. There are other suitable choices.

vic
 
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Midwestdrifter

Engineer In Residence
I like loctite 518 for dressing these gaskets. Give it 12 hours to set up prior to driving. If any gets into the cooling system, it won't harden.
 
I recently purchased a water pump from a local MB dealer to have as a back up in case mine fails.

My mileage at 230,000 miles or so, indicates I should act preemptively and replace it. I have maintained the cooling system as recommended and am of the feeling that until it fails, I will at least have the backup pump ready to go in.

Are there any indications that show when a water pump is beginning to fail?

When my next coolant replacement comes due, I may consider putting the new water pump in. Or not.
 

220629

Well-known member
...

Are there any indications that show when a water pump is beginning to fail?
...
There is nothing definitive that I'm aware of. A typical early failure warning is that the shaft seal will drip coolant.

A possibility might be to use a mechanics stethoscope to listen to the bearing noise. It will be subjective, but after a few listening sessions are performed that could provide a baseline of "normal" noise. From there you can listen for changes in the sound(s).

If you try it be VERY careful around the rotating parts.

:2cents: vic
 
It depends on where the edge is and how it is arranged; perpendicular or parallel to the gasket area.
Good call. The imperfection was perpendicular to the gasket (ie it would cause a leak) BUT it was on an interior edge where a tiny leak would not be a big deal. I decided to just leave it and not possibly mess anything up with the crude sanding/filing tools I have. Just gonna use the metal gasket as-is. Thanks all!

Also others were asking about removing the transmission cooling lines: I pinched the two hoses with vice grips (too keep fluid from draining out of the trans body) and the fittings came off fairly easily. Maybe 1/2 a liter came out of the radiator? Then I taped some plastic bags over the ends to keep them clean. Pretty easy, I'd do that again if your fittings look not bad, the access is awesome!

IMG_20200613_154954.jpg

Also, check out in the pic below how the pump impeller can rub the engine block. I wasn't noticing any problems but idk it couldn't have been good. This is the first water pump change after I bought this van with unknown history, so idk what previous owners did to cause this. I took off an aftermarket pump with a paper gasket, perhaps the pump tolerances weren't good enough, or the paper gasket was thinner than the OEM metal one.

00000PORTRAIT_00000_BURST20200613173133223.jpg

Also check out how bad my tensioner pulley was! Here's what a new one should look like if you're trying to figure out if you should replace yours:

IMG_20200613_160401.jpg

Finally, inspect the two elbow fuel lines on the high pressure fuel pump while you're in there! Mine had cracked a lot on the inside from the engine heat. Might as well take the whole HPFP off and check the backside bolts too (search for a write-up on that).
 
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It appears that there is no indicator of an about to fail water pump.

This reaffirms my position in having one in the van ahead of time.

Listening with a stethoscope will be upcoming. No noticeable bearing noise is evident with my half deaf hearing.

The only concern is the current mileage that indicates I should be thinking about the replacement in the near future. Until I hear some bearing noise I should be good to go.

Thanks Aqua Puttana. Your sage advice is always appreciated on this invaluable resource.
 

Midwestdrifter

Engineer In Residence
Typical failure occurs when the seal wear out and the pump leaks. The other failure results from the bearing loosing axial alignment, resulting in a leak, and sometimes nosie. A worn bearing will show up with a direct inspection with the belt off. A leaking seal is obvious by the coolant trail from the weep hole.

While you usually get some warning, once in a while the failure comes on over the course of a few hundred miles.
 

220629

Well-known member
... I took off an aftermarket pump with a paper gasket, perhaps the pump tolerances weren't good enough, or the paper gasket was thinner than the OEM metal one.
...
Tolerances can be a problem, but often the fiber gasket is present when impeller rubbing is a problem. The general advice here on the Forum is to avoid the fiber type gasket and install only the OEM style metal gasket.

vic
 

RedRabbit

New member
T1N OM647 Engine Water Pump Replacement

2004 2.7L Water Pump Replacement


5 cylinder water pump leak leaking remove replace change install
190,000 miles. Slight coolant drip from seal. The pump didn't "fail".

Parts

GO5 Type Coolant. About 2 full mixed gallons without a complete system drain/flush. I used Zerex GO5 Formula Phosphate Free from NAPA. Advanced Auto didn't carry any GO5 product. They were insistent to use one size fits all. I don't recommend that.

[/HUGE SNIP}


Refill coolant per manual. I needed 2 gallons 50% mix. They say it takes about 3 heat/cool cycles for the level to stabilize.
AP/vic
Update on availability of Zerex Go5

As of Fall 2019 through Summer 2020 my local (east central Alabama, USA) Advanced Auto Parts has stocked both the ready-to-use (50/50) and concentrated (always use distilled water to dilute) Zerex G05 coolant. Might have been a corporate change of mind in the past couple of years.
Local O'Reilly's stocks the ready-to-use (50/50) but can have the concentrated in a day or so. Local NAPA has the concentrated in stock.
 

220629

Well-known member
I just ordered an engine coolant aka water pump at higher price than some other options from the local Mercedes dealership. When I picked it up it is a remanufactured unit. The parts person said that remanufactured parts are getting more and more common. It appears that the MB parts supply mode is changing. I assume that the 2 year parts warranty still applies even to reman parts. I didn't think to ask at the time.

2006WaterCoolantPump.jpg

When I ordered it over the phone they asked for the VIN last 8 digits of my 2006 Freightliner Sprinter. At first the numbers didn't get accepted. I offered to give my 2004 Dodge VIN. "Dodge numbers don't work at all." Eventually the 2006 VIN did work. During the conversation I gave him the full 2006 number string. I don't know if that helped or not.

Anyway. If a NAS aka NAFTA Dodge 2004 - 2006 OM647 owner wants to order a pump or other parts from a Mercedes dealership my 2006 Freightliner 2500 HC 140 Passenger VIN should work.

WDRPD644765967963

vic

Added:
A possible aftermarket pump.
I put HEPU on a year ago. It was good quality, and I couldn't tell it apart from the OEM part I removed. The link below says fuel hose, but its for the HEPU pump on Europarts SD.

 
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