After 2 New Shop Vacs in two years, which as you say burned up and were loud... Went to the Goodwill and found a small portable vac for 4 bucks.

Ran a Tube plug with a 1/2 hole in the center into the vac hose and 4 feet of 3/4 - 1/2" hose to the nose cone.

6 years and still running.

UncleSteve,

What we used to do was to drill a couple of 1/4 holes into the top part of the hose of the vacuum this allowed for some cooling air and did not reduce the suction.