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 > Diesel Discussion

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 01-04-2007, 02:29 PM
ncof300d
Guest
 
Posts: n/a
617 Engine Temperatures

Around August of 2006 I replaced the thermostat on my beloved 1985 300D. After the new thermostat the temperature gage would stay just below 90C.

At the end of December I replaced the radiator and thermostat on my 1981 300D. The radiator that I installed was not new, however, the core was very clean on the outside and as much as can be seen on the inside was as good as a re-core. The day after I drove this car on a local bypass and I kept the speed at 70-75 for about 30 minutes. The temperature ran around 95C. The next day I was on an interstate at the same speeds the temperature was again around 95C. (When I filled the mpg was 27.0!) In my day to day driving (25-55 zones) I have noticed that the temperature is 90-95C. These engine temperatures are in ambient temperatures of 30-45F. My concern is if I am likely to have engine temperature problems when it gets warmer.

Any thoughts, experience, or words of wisdom would be appreciated.
Reply With Quote
  #2  
Old 01-04-2007, 02:52 PM
Registered User
 
Join Date: May 2001
Location: Michigan
Posts: 1,373
I used to take my temp guage very seriously.

Now that I've had several of these cars and read tons of posts, I just allow for the guages to be off. I've never had one overheat and I've had guages reading well into the danger zones.

15, 123's later, I just don't trust the guage, but I do trust the indestructible 617's

diesel don
__________________
DAILY DRIVERS:
'84 300DT 298k (Aubrey's)
'99.5 Jetta TDI IV 251k (Julie's)
'97 Jetta TDI 127k (Amber's)
'97 Jetta TDI 186k (Matt's)
'96 Passat TDI 237k (Don's
'84 300D 211k Mint (Arne- Undergoing Greasecar Conversion)

SOLD:
'82 240D 229k (Matt's - Converted-300DT w/ 4 speed
Reply With Quote
  #3  
Old 01-04-2007, 03:08 PM
dieseldan44's Avatar
Registered User
 
Join Date: Nov 2006
Location: Boston
Posts: 2,018
my 617 right now stays around 100C no matter what and I tend not to believe it either...FWIW I have a new thermostat in hand and am waiting to replace it.

is there a definitive way to test that temp readout?
__________________
-------------------------------
'85 300D, 'Lance',250k, ... winter beater (100k on franken-Frybrid 3 Valve Kit)
'82 300D, 'Tex', 228k body / 170k engine ... summer car
'83 300TD Cali Wagon 210k, wife's car
Reply With Quote
  #4  
Old 01-04-2007, 03:12 PM
lutzTD's Avatar
Registered User
 
Join Date: Oct 2006
Location: Lutz, Florida (N of Tampa)
Posts: 2,458
I bought a cheap meat thermometer from Wal-Mart I stick in the fins of the radiator..... or you could try something more modern like an IR laser reader. these are pretty cheap now. I saw one on the counter at Pep Boys for around $40.
__________________

1982 300CD Turbo (Otis, "ups & downs") parts for sale
2003 TJ with Hemi (to go anywhere, quickly) sold
2001 Excursion Powerstroke (to go dependably)
1970 Mustang 428SCJ (to go fast)
1962 Corvette LS1 (to go in style)
2001 Schwinn Grape Krate 10spd (if all else fails)
Reply With Quote
  #5  
Old 01-04-2007, 03:30 PM
dieseldan44's Avatar
Registered User
 
Join Date: Nov 2006
Location: Boston
Posts: 2,018
is the temperature taken from somewhere on/in the radiator? Would it be fair to stick a thermocouple between the fins?
__________________
-------------------------------
'85 300D, 'Lance',250k, ... winter beater (100k on franken-Frybrid 3 Valve Kit)
'82 300D, 'Tex', 228k body / 170k engine ... summer car
'83 300TD Cali Wagon 210k, wife's car
Reply With Quote
  #6  
Old 01-04-2007, 03:39 PM
NoCalMer's Avatar
Registered User
 
Join Date: Nov 2005
Location: California
Posts: 211
The most accurate way I know of is to replace the factory sending unit which is in the block and has contact with flowing coolant with an aftermarket one which is calibrated. Sometimes they come with adapters and you can make everything fit with out much modification. A good temp. aftermarket guage with sender is not very expensive and will give you a absolute temperature within a few degrees.
__________________
85 300D Turbo

Last edited by NoCalMer; 01-04-2007 at 03:46 PM.
Reply With Quote
  #7  
Old 01-04-2007, 03:43 PM
ncof300d
Guest
 
Posts: n/a
One thing that is good about the 'new' temps. on my 1981 is the MPG at highway speed.
Reply With Quote
  #8  
Old 01-04-2007, 03:43 PM
NoCalMer's Avatar
Registered User
 
Join Date: Nov 2005
Location: California
Posts: 211
Quote:
Originally Posted by dieseldan44 View Post
is the temperature taken from somewhere on/in the radiator? Would it be fair to stick a thermocouple between the fins?
It would be close in the fins of the radiator but the best place is in the block and in the coolant. That is where you really care about the temperature so you can pull over before engine damage occurs.

Mine reads around 90 C usually but has gone up to 110 C on a hot day.
__________________
85 300D Turbo
Reply With Quote
  #9  
Old 01-04-2007, 03:55 PM
Registered User
 
Join Date: Jan 2006
Posts: 138
replaced the leaking rad and temps rose 10C
replaced the encrusted temp sender and they dropped 10
??
__________________
Bill

'82 300SD 195K
'84 300SD 199K
Reply With Quote
  #10  
Old 01-05-2007, 12:37 AM
Gurkha's Avatar
Satyameva Jayate Ad vitam
 
Join Date: Jun 2003
Location: Boondocks
Posts: 1,026
Just for your peace of mind, try changing the VDO temp sender and also check the earth of the vehicle, these two have been known to give heartburns on these vehicles from time to time.
__________________
99 Gurkha with OM616 IDI turbo

2015 Gurkha with OM616 DI turbo

2014 Rexton W with OM612 VGT
Reply With Quote
  #11  
Old 01-05-2007, 07:26 AM
Shorebilly's Avatar
Marine Engineer (retired)
 
Join Date: Aug 2006
Location: West Virginia
Posts: 1,268
Thermostat

Quote:
Originally Posted by Gurkha View Post
Just for your peace of mind, try changing the VDO temp sender and also check the earth of the vehicle, these two have been known to give heartburns on these vehicles from time to time.
For you folks who are unfamiliar with British English......Earth is Ground in American English.......makes sense though, block ground would have an effect on the reading of the Temperature sensor.....

I just changed my Thermostat a couple of days ago......because I had begun to notice that my temperatures were increasing from a base of 95 C about 4-5 degrees or so when going up a long hill.......I paid high dollar for an official MB part from the dealership, because I wanted to know, absolutely that my thermostat would be operating in it's proper temperature range......now car runs at 90 C, but still fluctuates when going up a long hill.....

SB
__________________

Diesels:
'85 300D, "Max, Blue Benz", 155K, 27.0 MPG
'84 190D 2.2, "Eva, Brown Benz", 142K, 40.2 MPG
'77 240D (parts car)
'67 Eicher ES 202 Tractor "Otto" (2cyl, Air Cooled, 30HP)
Gassers:
'94 Ford F-150, "Henry", 170K (300 Six) 17.5 MPG
'85 190E 2.3, 148K....Parts Car
'58 Dodge W300M Powerwagon (Flat Fenders) Less than 10 MPG
Reply With Quote
  #12  
Old 01-05-2007, 07:34 AM
Shorebilly's Avatar
Marine Engineer (retired)
 
Join Date: Aug 2006
Location: West Virginia
Posts: 1,268
Changing out thermostat

Quote:
Originally Posted by dieseldan44 View Post
my 617 right now stays around 100C no matter what and I tend not to believe it either...FWIW I have a new thermostat in hand and am waiting to replace it.

is there a definitive way to test that temp readout?
Just in case you haven't access to MB shop manuals......and if you have a factory thermostat......there is a little arrow stamped into the thermostat, around the edge.......this arrow points up......

The Thermostat that I removed was manufactured by MotoRad of West Germany.....and it did/does not have the arrow.......

The new one is part # A 617 200 18 15.....and it does have the arrow......

SB
__________________

Diesels:
'85 300D, "Max, Blue Benz", 155K, 27.0 MPG
'84 190D 2.2, "Eva, Brown Benz", 142K, 40.2 MPG
'77 240D (parts car)
'67 Eicher ES 202 Tractor "Otto" (2cyl, Air Cooled, 30HP)
Gassers:
'94 Ford F-150, "Henry", 170K (300 Six) 17.5 MPG
'85 190E 2.3, 148K....Parts Car
'58 Dodge W300M Powerwagon (Flat Fenders) Less than 10 MPG
Reply With Quote
  #13  
Old 01-05-2007, 08:16 AM
dieseldan44's Avatar
Registered User
 
Join Date: Nov 2006
Location: Boston
Posts: 2,018
Quote:
Originally Posted by Gurkha View Post
Just for your peace of mind, try changing the VDO temp sender and also check the earth of the vehicle, these two have been known to give heartburns on these vehicles from time to time.
This makes a lot of sense. I think my car has some funky electrical issues anyway. Will do this. Thank you. Does the speedo work electrically as well, or is it purely mechanical?

Shorebilly - Thank you for the tip. I got the Behr tstat from Phil. is that what you got from MB as OE?

dd
__________________
-------------------------------
'85 300D, 'Lance',250k, ... winter beater (100k on franken-Frybrid 3 Valve Kit)
'82 300D, 'Tex', 228k body / 170k engine ... summer car
'83 300TD Cali Wagon 210k, wife's car
Reply With Quote
  #14  
Old 01-05-2007, 08:48 AM
Shorebilly's Avatar
Marine Engineer (retired)
 
Join Date: Aug 2006
Location: West Virginia
Posts: 1,268
Don't know for sure.....

Quote:
Originally Posted by dieseldan44 View Post
Shorebilly - Thank you for the tip. I got the Behr tstat from Phil. is that what you got from MB as OE?

dd
The OEM part had a BBE (I think) mark on it......bid not say Behr or any other company that I am familiar with......did have the star and the part number stamped into it......cost me $25.00 and because I decided to do this project to the MB spec....I also paid $19.50/gallon for MB antifreeze.....have not added the new antifreeze....yet.....am still flushing the old, improper, green stuff from the system......need to run over to the dealership and get a new radiator drain plug, today......old one broke, partially......it's plastic with an "O" ring.......still works, but I want to feel secure......so I have filled, run the car, and drained the radiator 2 x so far.....when I do refill with the proper antifreeze, I will use distilled water to top up.....my well water has a good bit of calcium in it, and is mildly alkaline......

SB
__________________

Diesels:
'85 300D, "Max, Blue Benz", 155K, 27.0 MPG
'84 190D 2.2, "Eva, Brown Benz", 142K, 40.2 MPG
'77 240D (parts car)
'67 Eicher ES 202 Tractor "Otto" (2cyl, Air Cooled, 30HP)
Gassers:
'94 Ford F-150, "Henry", 170K (300 Six) 17.5 MPG
'85 190E 2.3, 148K....Parts Car
'58 Dodge W300M Powerwagon (Flat Fenders) Less than 10 MPG
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 07:33 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2011 Pelican Parts - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page