vaccuum brakes

[hoppercar]

I decided to give vaccuum brakes a try, just on the tender of my new locomotive. I have never used vaccuum brakes,, and have no experience with them. when testing the vaccuum ejector, blowing compressed air thru it, I could feel it suck pretty good on the end of my finger. when hooked up to the tender system, and blowing air thru it, it very easily moves the vaccuum diaphragms and tightened up the brake shoes very well. I thought, wow, this might work pretty good for just trying it out on tender brakes. ....but when running steam thru it..NOTHING...it doesn't even try to pull a vaccuum or move the diaphragms. ...does anyone have any ideas what's wrong ?

[Fred_V]

Do you have a shutoff supply valve going to your brake valve? If so try throttling the steam. I found that I have to do that and I hooked a vacuum gauge to the ejector to find the sweet spot.