Author Topic: VDO Water Temperature Sending Unit  (Read 4730 times)

smiledoc

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VDO Water Temperature Sending Unit
« on: November 01, 2014, 14:31:24 »
I'm having difficulty finding a part I need.  The Mercedes Restoration Center parts dept. says it's no longer available.   I find that hard to believe.    My car is a USA version 280SL 1970 (manufactured in Sept. 1969)    Here's the info on the unit I can make out.     VD 9.69, then 6   24v 3w, then 17 +-3 deg c, then 20 deg c, then 11/20/01.

If you can help, please let me know.   There may be substitute parts that work just as perfectly as the OEM.    The MB Restoration Center is obviously restoring w113s, so they are using "something" if indeed this part is unavailable.   


Jonny B

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Re: VDO Water Temperature Sending Unit
« Reply #1 on: November 01, 2014, 16:01:57 »
This is part of the rudimentary emissions set up on the car. The part is NLA, but the replacement is 006 545 14 24. I have attached a picture of one that I purchased a couple of years ago. I just glued the one in the car (as in your picture) together so it looks alright. It is not really necessary. This replacement unit is about 5 cm/2" long.

I found one reference from jeff280SL:

"The temperature switch on top the thermostat is known as the 100 degree C or 212 degree F switch.  On the later USA versions this switch is part of the emissions system. When the temperature exceeds 212 this switch activates the two way valve and ignition timing advances.  This causes the idle speed to increase and I imagine fuel is burned more completely and emissions are reduced.  You can use this switch to turn on an aux fan although the temperature is a liitle high.  I suggest you consider a separate adjustable thermostat from the after market.  Weather is getting better so the overheating issue will become active again.  You may want to consider a heater hose bypass.  Search on the topic for details."
Jonny B
1967 250 SL Auto, DB 568
1970 280 SL Auto, DB 904
1966 Morris Mini Minor

smiledoc

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Re: VDO Water Temperature Sending Unit
« Reply #2 on: November 01, 2014, 16:32:15 »
This part is definitely a water part.    Not emissions.   Thanks for the response but I don't think we are on the same page. 

69280sl

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Re: VDO Water Temperature Sending Unit
« Reply #3 on: November 02, 2014, 01:34:33 »
Doc

I think you misread or misunderstood Jonny B's info.

Gus
Gus

68 280sl, signal red/ beige/black softtop. Car # 1084

smiledoc

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Re: VDO Water Temperature Sending Unit
« Reply #4 on: November 02, 2014, 14:48:53 »
Thanks everyone.   I was able to find the exact part I needed for sale on eBay by a store in Marin Co., CA.   They had a few of these NOS in stock and are shipping it to me Monday am.   I still find it hard to believe that the Mercedes Classic Center could not get with VDO and stock this item!   Seem ridiculous to me that they of all people did not have it to sell.   

Naj ✝︎

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Re: VDO Water Temperature Sending Unit
« Reply #5 on: November 02, 2014, 18:42:41 »
This is part of the rudimentary emissions set up on the car. The part is NLA, but the replacement is 006 545 14 24. I have attached a picture of one that I purchased a couple of years ago. I just glued the one in the car (as in your picture) together so it looks alright. It is not really necessary. This replacement unit is about 5 cm/2" long.

I found one reference from jeff280SL:

"The temperature switch on top the thermostat is known as the 100 degree C or 212 degree F switch.  On the later USA versions this switch is part of the emissions system. When the temperature exceeds 212 this switch activates the two way valve and ignition timing advances.  This causes the idle speed to increase and I imagine fuel is burned more completely and emissions are reduced.  You can use this switch to turn on an aux fan although the temperature is a liitle high.  I suggest you consider a separate adjustable thermostat from the after market.  Weather is getting better so the overheating issue will become active again.  You may want to consider a heater hose bypass.  Search on the topic for details."

JB,

From the figures quoted, it would seem that the switch he is looking for is the 17°C switch which fits on the left of the engine block (1970/71 US cars only) and not the 100°C switch on the t/stat housing. Smiledoc please confirm location...
This one is also emissions related as jeff said.
68 280SL