Hi I had Conway running this evening and I have a problem with the engine blower (not the steam blower). It's so fierce that even when running I'm constantly blowing the safety valve. Also I constantly have a shower of sparks. This is enough to draw the fire into the bottom of the smokebox. The chimney top is getting so hot, it's gone a purple colour. Do I increase the jet size or reduce it to reduce the draught from the engine? Thanks for any assistance on this problem. Cheers Ken MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.