Author Topic: Mercedes 6.9: Water Pump Overhaul  (Read 463 times)

jllgd

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Re: Mercedes 6.9: Water Pump Overhaul
« Reply #15 on: 06 October 2019, 01:50 PM »
Thanks to all for replying and commenting on this 6.9 water pump subject.
And a special thank to UTn_boy for summarizing all the pump parts with their part numbers. I think it's the first time I've seen these listed like that.
Appreciate it.

As it looks now I might purchase a refurbished pump from Mercedes Benz.
And as far as I know these are in stock.

I probably want to keep the old core for later use, since the core value is only about $111 as Harv mentioned. I believe I can keep the core if I want to?
Perhaps some clever mechanic can have it refurbished later.

UTn_boy

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Re: Mercedes 6.9: Water Pump Overhaul
« Reply #16 on: 06 October 2019, 02:38 PM »
I try to give part numbers out as often as I can.  They're extremely helpful!  Sadly, Mercedes has mandated a new policy to where dealerships can no longer give out part numbers.  Granted, it you have a close relationship with your parts guy that may not apply to you, but for most of us it will apply. 

And yes, you can keep the core.  You just won't get the $111 back they charge you up front.  And don't forget about seeing if Martin Werminhausen can rebuild the pump.  He's really good at what he does!  :)
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3l33ter

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Re: Mercedes 6.9: Water Pump Overhaul
« Reply #17 on: 06 October 2019, 04:22 PM »
I did a whole paper on this topic for the M100 Lodestar mag about 5 years ago............inc how to rebuild your own pump yourself....

I haven't had my 6.9 (nor known about the 6.9 specific communities) long enough to have that magazine. Any chance this paper / tutorial is somewhere online?



Timely topic for me - I am in the midst of reassembling my 6.9 engine after some major work. I was able to remove my water pump without removing the harmonic balancer by removing the pump with the housing attached. I can not figure out how to detach the pump from the housing! Anyone have any advice?

Once the pump is off by itself, I was going to attempt rebuilding it myself. I have done similar rebuilds before, though I am sure this will be the most delicate and difficult. If I can figure out how to do it and where to source the parts needed, I will share all of that info.
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jllgd

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Re: Mercedes 6.9: Water Pump Overhaul
« Reply #18 on: 06 October 2019, 11:40 PM »
Just found this vendor that seems to do 6.9 water pump repairs.
Based in Oregon.
Anyone here that have experience with them?

eBay link:
https://www.ebay.com/itm/1975-80-450-SL-SEL-6-9L-M100-Mercedes-Benz-Water-Pump-REPAIRING-Service-fix/362621699036?epid=1533929479&hash=item546df003dc:g:y6sAAOSwvzRXxM0p#viTabs_0

TJ 450

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Re: Mercedes 6.9: Water Pump Overhaul
« Reply #19 on: 07 October 2019, 04:49 PM »
Not sure about this eBay unit, it looks to be a different seller to previous ones. I have noticed Star Motors NY have the 6.3 pump listed. It would be worth enquiry as the price is good. https://www.ebay.com/itm/water-pump-for-Mercedes-300SEL-6-3-M100/302483228165?epid=16006939507&hash=item466d67c605:g:3SoAAOSwVgtZ3Ma7
1976 450SEL 6.9 1432
1969 300SEL 6.3 1394
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oversize

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Re: Mercedes 6.9: Water Pump Overhaul
« Reply #20 on: 10 October 2019, 09:27 PM »
Pumps are a common problem on the Benzes and it's mad parts are NLA for the M100.  Without going through the whole process which has been documented elsewhere, can the shaft be pressed out of the housing from the front, without having to remove the impeller?

If all else fails I'll have to get a new impeller made by CNC machine.
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TJ 450

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Re: Mercedes 6.9: Water Pump Overhaul
« Reply #21 on: 10 October 2019, 11:49 PM »
Nah, you've got to take the whole thing off and press it off from the impeller end (pull the impeller). It's definitely best left to someone who has done it before to save a lot of headaches.

Tim
1976 450SEL 6.9 1432
1969 300SEL 6.3 1394
2003 ML500

jllgd

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Re: Mercedes 6.9: Water Pump Overhaul
« Reply #22 on: 12 October 2019, 01:26 PM »
I wonder how Mercedes Benz does the core overhaul, when there are no pump parts available? Shaft, mech seal, impeller, bearing etc.
Do you guys think it's wise to keep the core and not hand it over to Mercedes Benz?
Thanks

arcijack

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Re: Mercedes 6.9: Water Pump Overhaul
« Reply #23 on: 12 October 2019, 06:51 PM »
 i purchased a rebuilt pump from a fella on Ebay, has done real well with no issues, i replaced the pump myself was fairly easy i know for a fact i did not remove balancer
« Last Edit: 12 October 2019, 06:57 PM by arcijack »

TJ 450

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Re: Mercedes 6.9: Water Pump Overhaul
« Reply #24 on: 14 October 2019, 12:53 PM »
Arcijack,

Was that the square base pump?

Regards,
Tim
1976 450SEL 6.9 1432
1969 300SEL 6.3 1394
2003 ML500

arcijack

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Re: Mercedes 6.9: Water Pump Overhaul
« Reply #25 on: 14 October 2019, 06:16 PM »
yes