WCME & CME 2025

Maybe it would if it was running solo

 

Hi Al
I think this is a commonly held myth - in fact 34092 acquired the nickname “The Volcano” before the Giesl ejector was fitted in 1986, some way into its 1981-1988 period of main line operation. If anything, the Giesl elector may have mitigated the exhaust position slightly with the crisper blast.
Best wishes
Julian

 

My recollection from standing at Dulwich cricket ground all those years ago is that the 73A common user locos which included 34066-70 were all prone to filthy exhaust when working hard going up the 1 in 100, whereas the two Brits and the Arthurs were comparatively clean.

 

Just a hunch: Most of the coal in circulation at the moment is high in volatiles, which causes smoke. Normally you would control that by adjusting the firehole doors to get the right amount of secondary air.

On a Bulleid, the design of the doors means you don’t have much control - basically you have “shut”, “wide open” and only I think two other positions in between. So it is hard to adjust the doors to a position that is “just right”; the likelihood is that you have too much secondary air (which cools the firebox and reduces steaming) or too little (which causes smoke). In the circumstances I suspect most firemen would err on too little, with the resulting smoke. The adjustment is not helped by virtue of the fact that the doors are also heavy to move, which discourages trying to find a good adjustment.

By contrast, on a Britannia with sliding doors, essentially you have infinite control of the secondary air so it is easier to find the spot where you just get a haze at the chimney, even with coal with a lot of volatiles.

Tom