Paul Dietrich 19 #1 Posted August 3, 2021 Today I removed the air filter base on my 1996 520 H just to clean. I noticed a small rubber hose that is connected to a hose barb on the base of the filter. This hose was not connected to anything on the other end. Question:...What purpose is this hose for ???..It does allow unfiltered air to be drawn in to the carburetor..Many years ago I had a 1989 520 H and I don't recall it having one of these hoses. Thanks in advance.... Share this post Link to post Share on other sites
Ed Kennell 42,139 #2 Posted August 3, 2021 The hose should be connected to the dirty air filter sensor behind the dash. Most connectors are broken off. Share this post Link to post Share on other sites
lynnmor 7,856 #3 Posted August 3, 2021 The switch is a World Magnetics PSF101 8111-150 if you need one. I bought from here some years ago. Often the switch has the nipple broken off and are difficult to repair, but I have done a couple. Share this post Link to post Share on other sites