hi

im currently in collage going to school for automotive and im doing engines, well i have an 87 t2 rx7 that will not idle due to an vaccume leak that i can't seem to find. On pistion engines we use something called a cylinder leakdown test to find out where its lousing compression / vaccume is this a safe test to use on a rotary engine just wondering??? thanks

 

Just spray brake cleaner while the engine's running. When the spray gets on the area of the vacuum leak, the idle will sputter. That's the area you wanna look at more closely.

 

there is not idle at all. it will start just to like jump to where its spost to idle @ and than stall shut off when its cold and than if i hold of foot on the gas for like 5mins and hold it ay 2000rpm's (let it worm up) it will idle @ 1krpms for like 2-3 minits than stall out agin. ive replaced all my vaccume lines with new silicone hosees and its make no differance what so ever. but if i adjust the throttle stop screw i can make the screw hold the throttle open at 2k rpms. is there anyother way to find a vaccume leak???

 

are you sure it is a vaccuum leak?

 

You can do a cylinder leakdown test, but it won't get you much of anything useful. I actually wouldn't expect the rotor chambers to hold much pressure for long, just due to the inefficiencies of sealing a rectangle.

-=Russ=-

 

Does your shop class have a smoke machine? That will tell you where your leaks are.