I noticed that my car was leaking a lot of oil. After inspection I found a piece of metal that broke off the bottom of the fuel pump. The picture shows the bottom of the fuel pump reflected in the mirror. I started the car and realized that oil is coming out of the hole. Just found this to be an interesting problem, which I wanted to share.

A closer photo

Very interesting---I have never come across that problem before. When you replace the pump be aware that the 500 and 126 pumps are slightly different in shape. If you have an alternator on your engine you will need to fit a later 126 pump---it has a sloping base which makes it a lot easier to remove/fit. You can fit a late 126 pump onto anything, but you will find it very difficult to fit a 500 fuel-pump onto an engine with an alternator.
When you do replace the pump, check that the operating pin, which comes across from the camshaft is protruding out the correct amount. Inclusive of gasket thickness (which you add or remove as required) the pin should protrude 1-1.5mm when fully out. Don't forget that you will have to turn the engine over TWICE to get the full range of the pin's movement (it is operatedby the camshaft which turns at 1/2 engine speed)

Quick correction if my memory serves me well. The 1-1.5mm protrusion is the minimum for the pump actuating rod with a 4mm max. Normal gasket sets have a thick and a thin gasket. The thick one should go under the fuel pump spacer against the crankcase , thin under fuel pump to avoid the risk of deforming the fuel pump mounting flange.
Getting very warm here in NZ by the way [emoji3]

You are quite correct David---the thick gasket goes on 1st, followed by the spacer and then the thin gasket. The 1-1.5mm projection of the pump-rod (when it has gone through the gaskets and the spacer) is at the START of the actuation, NOT the end. I stand corrected and suitably chastised---teach me to think when I am reading!