Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help




Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 09-24-2017, 12:10 PM
Registered User
 
Join Date: Oct 2011
Location: NJ
Posts: 35
1987 420SEL Water Pump Replacement Questions

I woke up to a nice sized puddle of coolant under the front of my 1987 420SEL this morning. Coolant is definitely leaking from the front of the engine, i can't see exactly from where but by running my hand under the pump reveals its wet, so I'm guessing the leak is from the Water Pump.

I looked up the PeachParts DIY water pump replacement article and have a few questions:
  1. is there something other than the water pump in the front of the engine that could be leaking coolant?
  2. Assuming it is the water pump, what one should i buy? I'm not rich...the prices range from $441 to $84?
  3. What else besides the pump should i replace? thermostat, fan clutch, belts, hoses? the belts are 5yrs old and in good shape. hoses look fine.
  4. Why do i need to remove the radiator? there appears to be plenty of room to remove the fan, then pull the pump.
  5. What else do i need to consider when doing this job?

Thanks, any help is appreciated.
__________________
1987 420 SEL | 87k miles
Image Gallery
Reply With Quote
  #2  
Old 09-24-2017, 01:03 PM
sixto's Avatar
smoke gets in your eyes
 
Join Date: Jun 2000
Location: SF Bay Area
Posts: 20,115
Have you been losing coolant? Is there axial or radial play in the pump pulley?

Sixto
98 E320s sedan and wagon
Reply With Quote
  #3  
Old 09-26-2017, 03:09 PM
Registered User
 
Join Date: Oct 2011
Location: NJ
Posts: 35
Quote:
Originally Posted by sixto View Post
Have you been losing coolant? Is there axial or radial play in the pump pulley?

Sixto
about 3 weeks ago my coolant level light came on and it was low so i added 1 qt. couldn't see any leaks. then last week it came on again. i parked the car, came out and saw the fluid on the ground. again, about 1qt. Its hard to check for play in the WP with 5belts on there so I'm going to go ahead and just replace the pump and thermostat.
__________________
1987 420 SEL | 87k miles
Image Gallery
Reply With Quote
  #4  
Old 09-27-2017, 06:39 AM
Registered User
 
Join Date: Aug 2002
Location: Southeastern PA
Posts: 2,969
metaprinter, buy a remanufactured water pump from your local MB dealer. You will need to pay a core charge if you do not give them the old water pump. Check the condition of the coolant hoses and drive belts before automatically replacing them. It would be a good idea to replace the thermostat. You should not need to remove the radiator, although I have never worked on a 126 vehicle with a V8 engine. Make sure the O-ring that seals the water pump at the block remains in place during the installation.
__________________
Fred Hoelzle
Reply With Quote
  #5  
Old 03-18-2018, 11:25 AM
Registered User
 
Join Date: Oct 2011
Location: NJ
Posts: 35
UPDATE: In order to replace the water pump on a 420SEL you do indeed need to remove the radiator as well as the distributor and the harmonic balancer...i kid you not. While i was in there i changed all the belts, hoses, thermostat.
__________________
1987 420 SEL | 87k miles
Image Gallery
Reply With Quote
  #6  
Old 03-19-2018, 09:53 AM
Registered User
 
Join Date: Aug 2002
Location: Southeastern PA
Posts: 2,969
metaprinter, it's surprising that MB would design a vehicle that required that much disassembly to replace the water pump ... another reason to avoid buying a MB with an 8-cylinder engine, or at least that vintage MB with an 8-cylinder engine.
__________________
Fred Hoelzle
Reply With Quote
  #7  
Old 03-19-2018, 01:01 PM
Hit Man X's Avatar
I LOVE BRUNETTES
 
Join Date: Sep 2004
Location: FUNKYTOWN
Posts: 8,958
Thumbs up

I left the dizzy in the 560 when I did the water pump. Somewhere I reported this could be just due to the deck height differences between the M116 and M117. So try doing this without pulling it. Maybe you just need to pop the cap.

Balancer removal IS required. But, while that far in, you should replace the front main too. Thermostat 100%. If your rad hoses are original, swap them. Keep the old two for roadside repair in your trunk tool kit.

Why avoid a V8 MB? The original pump lasted 30 YEARS. I replaced mine when I rebuilt the intake manifold and fixed many oil leaks. Figured prudent while in there.

It sounds much more difficult than it really is to do to this. The balancer is not pressed on, it just bolts to the hub.
__________________
I'm not a doctor, but I'll have a look.

'85 300SD 243k
'87 300SDL 251k
'90 300SEL 322k
'91 560SEL 183k

Eight others from IH, BMW, GM, Ford, and Volvo.

Liberty will not descend to a people; a people must raise themselves to liberty.
[/IMG]
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 11:09 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page