Hi,

Our '97 C280, c202 M104:

On dip-stick tube, about 1cm below the rim, is a small (1-2mm dia.) hole.

Quite sure it has always been there but this is first I notice.

Anyone know why a hole is put there by MB?

Thks in advance.

I think it's just a vent hole so pressure doesn't build up between the O-ring and cap and unseat the dipstick.

Duke

Makes perfect sense to me.
Looking closer, the hole seems to sit just below the o-ring on the stick platic cap/handle.

Thks.

cf

The hole on my dip stick tube is just below the plastic seat of the stick which places it well above the O-ring when the stick is seated.

If the hole was below the O-ring the crankcase would be vented to the atmosphere, which would violate emissions laws that have been in place since 1963 in the US, 1961 in CA.

Duke

Thank you very much, Duke.

Time to lift the bonnet again this weekend to quench my curiosity & get better acquianted with the little hole.

Cheers.

cf