Latest boiler regs?

The advantage of a mechanical pump is that it will add a small amount of water over a period of time so keeping the boiler topped up as the level drops when steam is drawn off. A hand pump unles syou wnat to be constantly working it will tend to put in a large amount of water quite quickly which will lower the temperature of teh water in teh boiler so you will end up loosing pressure and having to wait for it to rise again. I would go with one mechanical and one hand. You only need to return teh bypass water from teh mech pump into the tender not the trailer.

Its not usual to feed water into the bottom of the boiler so I would go with teh extra bush. Probably cheaper than a tee piece anyway.

J

Hi J.

he wouldn't let me use a 'T' piece as that was my first thought. it had to be a totally seperate water feed doing a mechanical feed was a simple enough job. I did think about a second hand pump, but as you say. I'll be spending more time pumping instead of watching where I'd be going lol. And yes, making a mech pump was cheaper than buying another hand pump. + once that's going you can more or less forget about pumping, and play instead.

Dave

Jason and Dave,

I think you are right about having 1 mechanical and 1 hand pump. I think that's the way I'll go too

Alan

Just out of interest can the PYRTE tick over without driving the wheels or is the chain drive direct off the crank with no way to put it in neutral?

J

Hi J,

The drive to the axle is live from the crank, so as the crank rotates, so does the axle. The drive pins in the hubs are the disconnect so it means the mechanical water pump, whether axle or crank driven are live all the time as the crank rotates.

It looks, Dave and Alan, that you will also need an extra bush in the top of the boiler (as well as the bottom for the mechanical water feed) as the water gauge needs to be isolated from other fittings, so cannot be used as a steam feed...

George

Thanks George, I was not sure if you could run the pump while stationary. Removing the drive pins is a bit of a PITA but I suppose thats the price you pay for a simplified design with not gearing so you can't put it in neutral and just have the crank turning.

Pump size will need to be adjusted if running from crank or axle to allow for less strokes as the axle rotates less.

J

Hi J,

Yes, the pump has a 3/4" stroke with a 1/2" bore as it's running at 1/16th speed of the crank, so that should do the job nicely, plus because its a slower motion there should be a better pumping action than a conventional crank driven pump as the balls will have better seating.

And like this the pump just bolts on the outside of the tender and is driven by the existing wheel hub. It's an easy fit.

George