radiator cap pressure question
 

I have a question, i see some of my friends cars have different radiator caps, some say 100 some say 120 and most say 140.
What is pressure for w116 with a turbo 617 engine?
What is pressure for a w123 non turbo with a 617 engine?
What is pressure for a w124 with a 603 turbo engine?

Thanks in advance

I think they just started raising the pressure over time with replacement caps. At some point they decided 1.4bar was best and started using those.

O'Reilly Auto Part temp fix
 

I noticed when I squeeze the upper radiator hose coolant goes right out the tank overflow line! My cap is not holding any pressure at all.

Since this isn't a "drive it while you wait for the part to come in" kind of issue, I checked the local boxes. My first stop, O'Reilly Auto Parts, had a 20 PSI cap on their shelf and even had the part number linked to my S350D in their computer. 1.4 bars is 20.33 psi, close enough for me. It was under $5, plus tax.

That will hold me until I can get an OEM or Mercedes cap.

Murrey Ultra, 7020, Ultra Radiator Cap, Made in Isreal, 1187tw, SKU 7 99304 07020 7

Felt like it was made out of thinner metal. Fit right on. Still might replace with OEM/MB cap, but will keep as a spare.

Jim

I got my new MB radiator cap from the dealer a week or so ago. It is built much better than the auto part store cap. $12 bucks or so. The "old" one is in the trunk as a spare.

Jim