vacuum engine running issues

[chizz]

Hi all

i recently built a vacuum engine and have had it running but it only runs for 30 seconds or so off the burner i have made it seems to be running fine then just seems to slow down and stop.

and advise would be much appreciated

thanks Chizz

 

[ghart3]

A possible problem might be the cylinder is getting too hot. If the flame is impinging on the cylinder and there is no heat sink the cylinder can get too warm and not enough cooling from the cylinder to form enough vaccum.

Have a little Duclos flame eater engine that when mounted to a large heat sink (brass ash tray) will run for hours if it don't carbon up in the cylinder from the flame.

Is it stiff and not easy turning after running and quits. If so your flame may be dirty (yellow flame) and the soot inhaled into the cylinder closes the clearance gap between piston and cylinder. Gary

 

[chizz]

thanks for the reply ghart3

it does have a heat sink as is bolted to an aliminum plate and the plate gets hot and the cylinder gets hot but you may be right if there is not enough difference between the flame and cylinder.

will look into that many thanks

Chizz