I have a vaccum gauge but I don't know how to use it on a rotary engine. Does anyone know? Also fluctuations in the readings, like differing readings, what do they mean in a rotary engine. I ask because in piston engines certain readings could mean sticking valves and stuff like that. Is there a chart somewhere similar to the one in this link for rotary engines?




http://www.iwemalpg.com/Vacuum_gauge.htm

 

I don't personally know of a chart or anything.. .but. .vaccum is vaccum.. If you need to test vaccum, just hook into the current vaccum system.. Throw a T in there somewhere, throw your guage on there.. But, depending on what you want to test... you would need to put it somewhere specific.. such as the 5-6port actuators, or what not. But a good place to tap in is the brake booster... I'm sure there is a better place, but thats the only easily accessable one I can think of right now.

 

There's not much to it really. You should see 25" on decel with the throttle closed from 3K or more RPM, about 17" at idle, 15-20" during cruise, atmospheric at WOT. These are going to vary somewhat depending on the condition of your engine. Once you get used to the kind of vacuum your engine draws under various situations you can then judge if something is wrong based on how that vacuum changes.