Thanks for the post John.

1. First, if you're running it on an extension cord, try eliminating it and plugging directly into the outlet.
2. If you're running it in a very cold ambient temp (below 40 deg F), try starting it in a warmer environment.
3. Check the copper contacts on the Pressure Switch. Once you take the plastic cover off of the on/off pressure switch you'll see the contacts, they may be rusty or varnished, which can cause this to happen. If so, take some emery cloth and clean them up a bit.
4. Check the main Supply Tube for debris, this can cause the switch to trip.

5. You have a bad Start Capacitor, this is probably the problem, MOST likely. Take the Cover off of the Motor/Pump Assy and take the leads off of the capacitor; you'll want to take a voltage meter (or capacitor tester if you have one) and test the Capacitor...it may be that it's dead or dying, not giving it enough "juice" to be able to kick the motor on right away; this is very common.

The Capacitor is item# 80 on the diagram, just click on the below link to view it:
www.mastertoolrepair.com/bostitch-parts-...200-pump-p-3320.html
Just click on "Click here for Pump Parts" beneath the main diagram on this page and you'll see a breakdown of the pump/motor assembly.

Also, you can find out exactly how to test the Capacitor in our "How To" technical doc, just click on the below link to view this info:



Thanks again and feel free to reply once you've started tackling this, we'll get to the bottom of it.
- MTR