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Radiator - petcock location
Sent to Car Experts September 03 05:58 PM

I want to drain the radiator (and flush) on my 1979 Mercedes 300 D but cannot see the petcock. There are two other heavy lines, in addition to the regular hose, running into the bottom of the radiator but no petcock. Can you tell me what to do or how I go about draining the radiator? Thanks for your help.

 

Optional Information:
Pre-1981 Mercedes-Benz 300 D diesel

Already Tried:
Just looking underneath the radiator where most petcocks are located.

Customer (name blocked for privacy)
Status:  Closed   Value: $8
Answer
September 3 6:21 PM (23 minutes and 9 seconds later)
         
ACCEPTEDCheck Mark

To be perfectly honest with you sir, the best option for draining your radiator (and engine) is to take off the bottom radiator hose at the bottom of the engine and drain it from there.

The reasons for this is 1: you can get more of the antifreeze out of the radiator and engine.

2: Petcocks often break or strip out when you try to open them, and when you do this, the only way to repair it (in most cases) is to buy a new radiator.

3: many cars do not even have a petcock.

One note: Please make sure you bleed the air out of the motor when you're filling the radiator with antifreeze.(many people have fried there motors because there were air pockets in their motors.

Russ



Russell S Wydra
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Wydranator -- Auto Mechanic100% Positive Feedback on 82 Car Accepts
30 years experience in automotive, motorcycle and small engine repair.
Reply
September 3 6:25 PM (3 minutes and 57 seconds later)
         
Reply to Wydranator's Post: How do I bleed theair out of the motor?
Customer (name blocked for privacy)
Answer
September 3 6:41 PM (15 minutes and 11 seconds later)
         
REPLIEDCheck Mark

Look around the thermostat housing. There is sometimes a little bleeder valve, or small bolt that you can take out.

You would fill the radiator until antifreeze starts to come out of this hole and then either close the bleeder valve, or put the bolt back in.

If you cant find a bleeder source, you can change your thermostat (which would be a good idea anyway) and leave the housing loose until antifreeze comes out of there.

Get back to me if you need any further assistance OK?

Russ



Russell S Wydra
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Wydranator -- Auto Mechanic100% Positive Feedback on 82 Car Accepts
30 years experience in automotive, motorcycle and small engine repair.
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September 3 8:17 PM (1 hour and 36 minutes and 17 seconds later)
         
Reply to Wydranator's Post: GOT IT RUSS! Thanks for your help.
Customer (name blocked for privacy)
Answer
September 3 8:23 PM (6 minutes and 30 seconds later)
         
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30 years experience in automotive, motorcycle and small engine repair.
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