Leaky Axle Box Gasket

Each of Sentinel 7109's axle boxes supports its corner of the loco on a plain bearing and has an oil bath in the bottom. A large sprung pad sits in the oil bath and is spring loaded against the lower surface of the axle bearing. The pad acts as a wick to lift the oil to the lower bearing surface. As the axle rotates, oil is carried round from the pad to the weight carrying upper surface.

Some time ago, I'd noticed that one of the axle boxes seemed to be retaining its oil level much better than the other three.

I checked whether there was any water under the oil in the offending box using an oversized horse-syringe (for want of a better name).

One of these

There was a lot of water!

On removing the covers from the two right hand side axle boxes, the oil retaining one showed signs that its gasket was split at the top. On further inspection, both the right hand side gaskets were in poor condition and weren't helped by being disturbed.

New gaskets were made for both of them. (As no problem has been apparent with the LHS boxes, they have been left alone).

Front RHS gasket of 1.5mm Rubberised Cork

With the cover on, the axle boxes look like this.

Assembled (complete with missing stud!)

The missing stud will be replaced, of course (and the wheels will be painted).

Note: These photos have been cropped. If there are any modellers wishing to copy the axle box detail, leave me a comment below. I have other photos with more detail that I can supply on request.