Vacuum pump test/reading 85 300TDT

[shear2001]

I connected my mityvac directly to the connection that is located near the cruise control on a 85 30TDT. I got reading of 6". I know it should be 17-21. Is this an accurate test? If so what is the best plan of attack. New, rebuilt or salvage yard? Any input is appreciated. Thanks, Brian

[95300YDT-A]

Shear,

A first cheap and easy thing to do : check first all those small "restrictors"
in the vacuum lines. They show up as interconnections between two lines
but in fact there is a callibrated opening in them. The different color stands for the size of the opening. The brown ones have an orifice of only 0.6 mm inner diameter and clog up from time to time causing all kinds of problems.
Fortunately easely solved once you know were to look!
Good luck,

Danny

[shear2001]

Thanks for the input, however I'm only getting a reading of 6" from the main line to the pump. I'm assuming that it should be more?

[95300YDT-A]

Shear,

On top of this forum are two treads mentioned : do a search and the W 123
DIY pages. On this last one there is the next site :

http://207.210.95.34/~boostd/

You will find the answer on all your vacuum questions there!

Danny