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 > Vintage Mercedes Forum

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 11-25-2004, 05:51 PM
Registered User
 
Join Date: Jun 2004
Location: Sydney, Australia
Posts: 29
Exclamation My worst nightmare - possible heater core leak !

I've been reading all previous posts regarding heater issues with the w108 and I think I have to face up to my worst nightmare...

I discovered a small coolant leak coming from the heater unit dripping down on the transmission well !

While under the dash and the engine running(at its operating temp) I openned and closed the heater taps and noticed coolant dripping from them.
So as explained in the previous posts I replaced the gaskets after discovering that the heater taps on the Oz models are at a different place from the US models (they're down low near the transmission well rather than up behind the ash tray or radio). All went well and finished the job in less than an hour coz the taps were so acccessible and NO MORE LEAKS . . . from the taps anyway.

It only lasted for a few days and then started again and I checked the heater taps and they're 100% not leaking!

I had the radiator replaced a few months ago and had it pressure tested again and all checked out fine and no cooling issues.

I'm worried that since the pressure is being maintained in the cooling system the problem is actually moving from one place to the next weakest point so to speak.

Can you please advise if there are hoses that connect the heater core to the pipes that come through the firewall? The MB Star Classic CD is no help with diagrams - just as a last possibility for leaks other than the HEATER CORE.

Can you please advise on how best I can tackle this one.

Cheers,

Ysmael


ps - it's coming into summer here and I've thought about bypassing the heater but I'm just avoiding the issue again.


Last edited by yogiysh; 11-25-2004 at 09:19 PM.
Reply With Quote
  #2  
Old 11-26-2004, 12:37 PM
Registered User
 
Join Date: Aug 2004
Location: Western Washington
Posts: 504
I had the same problem

I replaced my core with a new core for a 1984 Mercury Marquis.
Raidiator Barn.com has the dimensions on the website, so I just matched them up. Cost was $35.00 dollars.
__________________
1970 280S M130 engine- good runner
1971 250 M130 engine- #2 rod bearing, gone
1971 280SE (blown engine,parts car)
1977 German 280S W116-only 33 years old
Reply With Quote
  #3  
Old 11-29-2004, 05:11 PM
Registered User
 
Join Date: Jun 2004
Location: Sydney, Australia
Posts: 29
Thanks MunichTaxi, I might have to take the replacement option. I just enquired about the price of a recore for the heater core and it comes out to be the same prices as when I did the radiator !! - and that's with me doing the estimated 14hrs (if I new what I was doing) taking it out of the car in the first place.

I'm just working up the courage to start taking out the dash to get to the heater unit as I still don't know if it's the heater core or the connecting hoses.

Cheers,

Ysmael
Reply With Quote
  #4  
Old 11-30-2004, 02:16 AM
Registered User
 
Join Date: Jul 2002
Location: Raleigh, NC currently residing in KL, Malaysia
Posts: 460
Hello,
I have no experience with heater cores, but would it be possible for you to look into the area of the leak with a mirror and torchlight?
That may help you pinpoint the leak. There may already be someone in there before you that has done some *modification* that could be leaking now.
Just my 0.2 cents
__________________
Nachi11744
Reply With Quote
  #5  
Old 11-30-2004, 06:00 PM
Registered User
 
Join Date: Jun 2004
Location: Sydney, Australia
Posts: 29
Thanks nachi11744, there is no visiblity into the heater box to see the heater core or lines, even through the bottom vents when they're open. I can't believe how well packed everything is under the dash for such a big car - I can now believe they say that MB designed the W108 car around the heater unit !! ... Still a brilliant product of engineering though.

As a last resort prior to pulling everything out, I'm going to remove the windshield wipers and cowl cover, and leaf filters today to see or reach any of the heater lines.

Cheers,

Ysmael
Reply With Quote
  #6  
Old 11-30-2004, 06:46 PM
dmorrison's Avatar
Registered User
 
Join Date: Dec 2002
Location: Colleyville, Texas
Posts: 2,695
A little advise, since I had to replace the evaporator in the 300TD. TAKE DIGITAL PICTURES EVERY STEP OF THE WAY. IF YOU DON'T HAVE A DIGITAL CAMERA ---BUY ONE--. you will be much happier when you realize you forgot how something was assembled and you have the digital pictures.
Use the highest resolution on the camera and save them to a CD. I have them for the W123 dash removal and reasembly, So If anyone needs them or I need it. I have it.

After completely rebuilding a 65 Mustang and doing extensive work on the 82 300TD I realize how important the digital camera is.

Dave

PS be ready to "rebuild some things while your in there". You dont' want to do this again so you might as well do the little things while you have it apart. "while I'm at it itis" is a terrible delayer of car rebuilds.
__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car
Reply With Quote
  #7  
Old 11-30-2004, 07:31 PM
Registered User
 
Join Date: Jun 2004
Location: Sydney, Australia
Posts: 29
Thank you Dave for this great advice - I will be taking lots of pictures.

Just assessing what else needs to be done but so far not much - the timbers in the dash are pretty good apart from fading.

I've got European Wallnut which faded to a lighter shade but I'm sure I'll come across something along the way.

I'll check the AC evaporator but at this stage the AC doesn't leak and the only issue I need to address with the AC system is the lubrication maintenance.


Cheers,

Ysmael
Reply With Quote
  #8  
Old 11-30-2004, 07:57 PM
Benzcrusher's Avatar
Registered User
 
Join Date: Jan 2004
Location: Upstate SC
Posts: 1,114
I am convinced that MB had child or liliputian labor OR a severly hungover designer when it came to the 108/ 109 dash. That Behr heater unit is a ***** to get at... The clamshell halves are secured by many tiny spring steel clips, remove them all or you will break something.
The 108 heater is as stupid and counter-intutive as that thumb screw which holds the speedo cluster in place!!!
__________________
"Shabby" 1978 240D with a 300D motor
1997 Volvo 960 wagon 245K
Reply With Quote
  #9  
Old 12-04-2004, 01:11 AM
Registered User
 
Join Date: Aug 1999
Location: Florida / N.H.
Posts: 8,804
Many a 108 has wound up in the scrap yard cuz of a leaky heater core or bad blower motor...
The Straw that breaks the Camels back.....
Reply With Quote
  #10  
Old 12-04-2004, 06:32 PM
Registered User
 
Join Date: Jun 2004
Location: Sydney, Australia
Posts: 29
Not to worry, I won't be letting this one go that easily !!!

It was suggested to me also that since cooling system is maintaining the pressure and the leak is minor, to add a small amount of radiator stop leak into the coolant and see if it stops the leak.....hmmm.

I don't know if its worth a try.
Reply With Quote
  #11  
Old 12-05-2004, 11:23 PM
Registered User
 
Join Date: Jul 2002
Location: Raleigh, NC currently residing in KL, Malaysia
Posts: 460
Quote:
It was suggested to me also that since cooling system is maintaining the pressure and the leak is minor, to add a small amount of radiator stop leak into the coolant and see if it stops the leak
FWIW, Land Rover V-8s and Range Rovers were filled with a product called BARSLEAKS from the factory to reduce coolant leakage complaints on NEW vehicles.
If you do use a stop leak, pour in only half first and drive with the heater on FULL for a few days to stop the leak. The less of this stuff used, the better.
Just my 2 cents.

__________________
Nachi11744
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 11:41 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2021, 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