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-Benz Forum > Mercedes-Benz Tech Information and Support > Tech Help

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 07-07-2000, 12:56 PM
ANIAGBOSO, OGE
Guest
 
Posts: n/a
For quite some time now the water level in the cooling system of my 300E drops gradually. I've been topping it with about 0.6 litres of water every 2-3 days. I've taken the car to a mechanic who, after thorough investigation, could not discover any leakage point - I've even poured some colorful coolant to see if that could help detect the leak point (if any) - but no success.
* What could be the possible causes of this problem and what solution shall I apply?
* Could water be evaporating from the cap - the temperature guage never gets above 90 degrees

Thanks in advance for your suggestions.

Oge.

300e 1986

Reply With Quote
  #2  
Old 07-07-2000, 01:58 PM
yal's Avatar
yal yal is offline
Benz-smart
 
Join Date: Oct 1999
Location: New York, Long Island
Posts: 2,707
Do you see oil in the coolant tank? Or white smoke coming from the exhaust? These would be symptons of a bad head gasket seal.

88 230E (W124)
Reply With Quote
  #3  
Old 07-08-2000, 11:14 AM
imran
Guest
 
Posts: n/a
Check your waterpump - mine had to be changed
Reply With Quote
  #4  
Old 07-08-2000, 11:54 PM
Registered User
 
Join Date: Jan 2000
Location: New Bedford, MA USA
Posts: 1,583
There may be a leak in the heater box which might show on the carpets or it might drain via the AC drains. Look under the car after it's been running for a while and is fully warmed up. The HVAC system in the 300E is very complicated and has a lot of potential leak points. Be persistent, you will find it. BTW if your head gasket was either going or gone, it would most likely cause an over pressure situation in the cooling system that would be pretty obvoius to you if it existed.

------------------
Jeff Lawrence
1987 300e
1989 300e
1987 BMW 325
Reply With Quote
  #5  
Old 07-09-2000, 12:21 AM
surfnvet
Guest
 
Posts: n/a
Pop your hood and listen (in a really quiet area) after driving... any hissing? Look at the hood pad...Any spray? Touch under the water pump...any wet greasy feel? If its your heater box you should smell it with the heater on. Look at the auxiliary water pump. Bend all the hoses...should find it..Pressure check the system, thats an easy one.
Reply With Quote
  #6  
Old 07-09-2000, 08:08 PM
Registered User
 
Join Date: Mar 1999
Location: Suwanee, GA, USA
Posts: 4,712
On occasion, we have to pressure test some cars over night to allow for expansion and contraction of the hoses and seals. If this persists, just have your mechanic pressure test all night.

------------------
Benzmac:
Donnie Drummonds
1991 GMC Syclone
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM
Reply With Quote
  #7  
Old 07-10-2000, 06:15 AM
Registered User
 
Join Date: May 1999
Location: So. Burlington, VT
Posts: 78
Oge,
This is just a "shot in the dark" because as previously stated, the cooling system is complicated. I had a similar problem awhile back and added some dye to the radiator that glows when subjected to UV light. No leaks could be seen. The dealer said I needed a new radiator and new water pump. I didn't jump at the chance to spend hundreds of bucks when I saw no leaks in either....
It turned out to be a 80 cent O-ring in what I believe is a heater hose. Pull the air cleaner and look on the left side of the engine very near the firewall. The hose comes thru the firewall and does a 90 degree turn into the engine block. There is a bracket held by two bolts and has an O-ring seal. It was leaking a very small amount but has not leaked in over a year and the radiator and water pump are still going strong.
Reply With Quote
  #8  
Old 07-10-2000, 12:04 PM
ANIAGBOSO, OGE
Guest
 
Posts: n/a
Imran, robi99, Benzmac, Surfnvet, Jeffsr,

Thanks a lot for all your suggestions, hope the mechanic will find out the cause this time around.

Yal,
I can't notice any oil in the reservouir, however every morning when I start the engine, I usually notice some white smoke and some water vapour coming out from the exhuast. This stops ( or rather it's unnoticable) as soon as the engine is fully warmed.


Regards,
Oge.
300e '86
Reply With Quote
  #9  
Old 07-10-2000, 06:07 PM
yal's Avatar
yal yal is offline
Benz-smart
 
Join Date: Oct 1999
Location: New York, Long Island
Posts: 2,707
Oge,
That sounds fine. The smoke is just condensation in the pipes. When my waterpump went the leaking antifreeze was burnt off before reaching the ground. No leak was visible when cool. It wasn't until it got really bad that I found the leak.
Do you smell the sweet coolant smell when you turn on your vents? As you can tell from all the above responses the nature of the cooling system makes for a tough diagnosis. Even the benz dealer was fooled with my waterpump!? Have it pressure tested. Failing that, check the whole system hoses and all particularly the heater core. There are some good suggestions above hope this all helps.

yal
88 230E (W124)
Reply With Quote
  #10  
Old 07-10-2000, 09:41 PM
Robert W. Roe's Avatar
Registered User
 
Join Date: May 1999
Location: Lehigh Valley PA
Posts: 1,330
Since getting my expansion valve replaced, I've noticed a faint smell of antifreeze when I switch the system from AC to Economy prior to shutting off the engine. Is there anything in particular that I should look for? Thanks,

------------------
Robert W. Roe
1984 300SD 170K mi
Reply With Quote
  #11  
Old 09-19-2000, 12:16 PM
mattsuzie
Guest
 
Posts: n/a
Could it be your freeze plugs?

------------------
'89 420 SEL
'90 300 SEL
'68 Olds 88 Convertible
'84 300 SD (sold it)
Reply With Quote
  #12  
Old 09-20-2000, 04:56 PM
AucklandGuy
Guest
 
Posts: n/a
Re. the dropping coolant leak, I had the same thing in my 280E for a couple of months. A mechanic traced it to a leaking water pump, which fixed 50% of the drop. But the leakage continued, at a slower pace, until the head gasket blew.

------------------
1977 W123 280E
286,000km

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Coolant RED vs. GREEN CJ Tech Help 79 05-23-2009 07:07 PM
MB says it's okay to use Prestone Wm. Lewallen Diesel Discussion 26 12-24-2008 09:32 PM
Corrosion/Coolin Sys. Q? Steve7 Tech Help 42 07-05-2007 02:01 PM
100% Antifreeze?? 300EVIL Tech Help 11 03-16-2002 03:58 PM
Water Wetter compatible? Chris Haney Tech Help 33 06-16-2001 08:35 PM



All times are GMT -4. The time now is 05:49 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page