Oil reservoir and plunger

[nicky]

   Hello all,
 I have a Lister ST2 with 2 plungers that go thru the air shroud and screw into the intake manifold. I can find no reference to them in the Service manual. They are shown in the parts manual and just called an "oil reservoir and plunger".They look like they are closed on the bottom [ no orifice]. Are they for some kind of a starting aid or a pre-lube for the upper part of the cylinder before startup?

[dieselgman]

The oil reservoir has a small hole in its bottom to allow for oil injection into the inlet port to boost compression for cold starts.

dieselgman