Sunday, 20 March 2016

First Urmston visit for five weeks

A combination of several Sundays as signalman in Consall box, and Mothers' Day, meant I was not able to get to the Urmston & District Model Engineering Society's running track in Abbotsfield Park until today, five weeks since my last visit. But high pressure is still defining our weather and today was lovely - warm, sunny, and virtually no wind.

Soon after the last time I ran 'Alfred' I replaced the troublesome right hand injector, which has never worked properly, with a new one. Knowing I would not be able to attend Urmston for several weeks I had intended to steam 'Alfred' at home on rollers to check if the replacement injector had cured the problem, but the horrid cold weather meant I never got round to doing that. I was particularly interested today, therefore, to see how the new injector performed.

Once I had 'Alfred' blowing off (full boiler pressure) I let the boiler water level drop to about half a glass on the gauge glass as the steam escaped through the safety valve, then tried the left injector, to ensure it still worked (it did).

Time to try the new, right hand one. I turned the water supply for the injector on and immediately saw an improvement - with the old injector the water had merely dribbled out of the injector drain, now it poured out as it always had with the left injector. I turned on the steam supply to the injector and it immediately 'picked up'. I didn't even need to trim back the water supply as is usual with injectors before the 'pick up' - this one just worked! This boded well for hassle-free operation on the track; it can be quite busy on 'Alfred's footplate when running so an injector that reliably 'picks up' without needing to fine tune the water supply is a bonus. It transpires there was never anything wrong with the clack valve after all despite my earlier fears that that was the cause of the trouble rather than the injector itself.

Furthermore, this injector delivers water at a high rate for a small loco like 'Alfred' which adds to the options for the driver for topping up the boiler water level; the slow-feed left injector, the fast-feed right injector, and finally the tender hand pump.

So now 'Alfred' is 100% operational for the first time in my ownership. It is much more relaxing driving him knowing one has two reliable injectors and the hand pump and I had great fun doing so today. One of the club's more experienced drivers (and the youngest) drove him while I had my lunchtime sandwiches, and said he was a delight to drive.

The new right hand injector in place below the footplate (it's the black tube with three brass pipes and a plastic drain pipe attached). Note that on the trolley, 'Alfred' sits on rollers so the wheel tyres rather than the flanges carry his weight. These rollers can also be used when steaming the locomotive where no track is available, as can be seen in the video in the blog entry for 21st October 2015 when I steamed 'Alfred' at home.

The original faulty injector removed from 'Alfred', together with the data sheet that came with the new one. This shows it will deliver 25 fluid ounces (1.25 pints) of feed water per minute into the boiler, which is a lot for a small locomotive such as 'Alfred'. The data sheet shows that the injector has been tested and will 'pick up' at any boiler pressure between 42 psi and 120 psi. Once engaged, it can remain so at boiler pressures down to 23 psi. The old injector is wearing the shiny new brass pipe connectors that came with the new injector but are not required when fitting to an existing pipework system.

'Alfred' tonight back in the garage on his trolley. The tool kit that goes to site with him resides on the bottom shelf , with sundries such as water and pneumatic hoses and latex gloves on the centre shelf. The tender sits on the garage floor! The new injector can be seen under the footplate beneath the cab floor.

The trolley from behind. It's on wheels so can be wheeled out to the car, minimising the distance I have to carry the loco.


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