D.Maggs - workshop engine

[Jasonb]

Water in at the bottom and out the end.

You might wantto try loosening the top cap while it is running incase there is some trapped air. Or prime it by filling with water.

The good old suck and blow test should show if the valves are sealing. You should be able to blow through from the bottom or suck from the outlet but not the other way round.

[Michael S.]

The problem could be the air chamber.
You need to vent the pump a little at the top.

I've installed a vent screw at this location on two self-built pumps, as shown in the original blueprints.

Michael

[Sanjay F]

Thanks Jason/Michael

I'll give both your ideas a go, you can see it's trying, but very weak

[Charles Lamont]

If you lapped the valves to their seats it would probably pump air and prime itself. If not then priming it by filling from the top may well work as others have advised. To be authentic, the air chamber should have a plug at the top and one at the bottom (in the side). In time the cushion air dissolves in the water and the chamber fills up. A regular maintenance task is to remove both plugs to drain the chamber.

[Sanjay F]

I took the pump apart as the valves were catching, cleaned them up and they are moving freely. I tried the suck/blow test and its working, but not getting a 100% seal .......I'll try lapping the seats and the filling technique and see if things improve ...... just a little squirt is all I'm after, not a fireman's hose 

[PaulR]

Try squeezing the (upper) outlet pipe, you might get a clue from the back pressure.

[Jasonb]

A smaller dia lift tube may also help as the capillary action can help to stop the water dropping back down between strokes particularly until the pump is filled with water

[Sanjay F]

So much to learn about pumps, thanks. I haven’t got the right fitting to fit the bottom inlet so will probably end up making one.

[Sanjay F]

Gentlemen, we are pumping! 

I made a hole in the top of the air reservoir and reduced the size of the inlet pipe and hey presto we have water. The pump and mechanism have 'aged' somewhat since you last saw them...........strange.

https://youtube.com/shorts/7BjLwStSXmc?feature=share

Well that's another one done and thank goodness it was taking up a lot of workshop space. Thanks all once again for your help and guidance.

.....right what's next?

[crueby]

.....right what's next?

A larger pumping engine?   

[PaulR]

  Good to see you got it working in the end, it would've been annoying otherwise.