Air valve

Hi fellows,

I'm in the process of getting my 73' Mercedes 280se 4.5 back up and running.
I tested the air valve that was installed in the engine as well as a spare air valve I had on the shelf.
When testing both valves at 70 C hot water in a cup both air valves will close until about 2 to 3mm before being totally shut.
Is this acceptable or do they have to close fully? They both seemed to have acuated the same distance.
Much appreciated, greetings from western canada
Sven

Hi Sven,

I do not know how much time you gave them to close in 70°C hot water. They should fully close if you wait for some minutes. THis opening is rater romm temperature position.

Thank you for your reply doctor!

I tested both air valves again at 90C this time for 5 minutes and both valves close but still leave a 2 to 3mm opening.
I assume they are no good?
Cheers,
Sven

Hi Sven,

correct they are no good. Good news is that they can be repaired: jetronic.org/de/d-jetronic/zusatzluftschieber#Reparatur