Help: someone drilled a HOLE in fuel pump top

[KKRRSS]

Daughter bought a 77 Futura.
we are working on it.
there is a tiny hole in the mikuni fuel pump top half. Drilled by a drill bit, i can barely see light through it.

Was there a reason on these sleds that someone would do that.
with my understanding of the pumps operation it wont work, right?

 

[eddy]

Hole

JB Weld?

 

[Bocephus]

is it a diaphram pump like whats used on lawn mower engines? if so, they are supposed to have a hole in them

 

[KKRRSS]

It is a mikuni rectangle, one output, ont input, and one impulse line.
my old polaris uses the same pump, but no hole.

 

[TeamCassLake]

some diaphragm pumps have vent in them

 

[KKRRSS]

Using google I found that Rotax has a service bulletin suggesting using a mikuni pump with a weep hole, I learn something every day.
KRS

 

[Red Sketcher]

This is funny, I was priming my fuel system today, and I blew in the pulse hose, heard a leak, pulled the pump out and apart. Mine has 2 drilled dimples on the outside, with 2 directly opposite on the inside but only one pair actually breached through with just a tiny pin hole.