Dropped safety pin head into oil galley

INTOSILENCE1

MEMBER
2000 CHEVROLET S-10
2.2L
4 CYL
2WD
AUTOMATIC
130,000 MILES

I am changing out a broken timing chain. Behind the cam sprocket there is a small hole from which oil comes out to lubricate the timing chain. This hole, which is approximately one quarter inch in diameter, is plugged with a small metal cap which fits in pretty snug. The cap has a tiny hole right in the middle, about 1mm in diameter, for oil to leak out. Since it is recommended to change out this plug along with the chain and sprockets, I drilled through the little hole to make it bigger and then used a pick to try to hook it and pull it out. On one of my final attempts, I straightened a small safety pin to use the head of it as a hook. The head of the safety pin broke right off and went flying into the hole. I tried to pull it with several things but nothing comes out. What could happen if I just let it be? How can I take it out? Where does this oil galley lead? Any tips are appreciated. Thanks.

The hole I am talking about is in the center of the picture, the one that has four lines around it like a bulls-eye.

Image (Click to make bigger)

1 Reply

STEVE W.

MECHANIC
12,963 POSTS

That plug will not pull out until you remove the four staked areas (bulls eye) that retain it. Once you use a small tool like a dremel or die grinder to remove those then drill the hole a bit larger and screw a larger sheet metal screw into it and pry it out.
Behind it you will see the oil gallery and can retrieve the metal piece. The reason you do not want to leave it in there is that it will be pushed toward the hole by the oil pressure and then will likely end up in the chain.