Vacuum line size

[Park]

I replaced mine with 5/32 because that seemed to be the closed to the size I was taking off of the manifold and engine. They went on, and seemed snug, but in no time at all they were loose. I wrapped electrical tape around a couple metal nipples to tighten them up, and that helped, but only those.

 

Use the 7/64" vacuum lines. They are a bit more difficult to put on, but they aren't going to leak.