Vaše rešenje, "otvor za curenje", dobro je, ali bi bolje reći "otvor za kontrolu curenja (zaptivenosti) jer u normalnoj situaciji kroz otvor ništa ne curi. Evo i objašnjenja sa date Internet reference:

Previous pump seal assemblies have typically used one or two neoprene seals
that are press-fit into an aperture in a housing wall. Different types of
fluid are thereby isolated across opposed faces of the wall. In the case
where two neoprene seals are utilized, these may be spaced apart along the
length of the shaft to define a cavity therebetween, and the housing wall
may have a vent opening that communicates between the outside atmosphere
and the cavity. This vent opening is also known as a weep hole, because it
is possible to see liquid pouring out of the hole after one of the seals
has failed. In the dual-deal system, one of the seals may prevent fuel
from communicating with the vent hole, and the other seal may prevent
lubricating oil from and accessory drive mechanism from communicating with
the vent hole. It is typically assumed that the seal assembly is
completely intact unless liquid is visibly present at the exterior weep
hole, since the pumps typically operate with fuel circulated in contact
with the seal for cooling purposes at positive internal pressures ranging
between about 3 to 5 psig.