I have a 92 W250 and when I start it first thing in the morning it shakes and blows white smoke out for about 30 seconds until the engine gets a little internal temp. I Figured the KSB. I checked the voltage at the KSB wire with a cold manifold (Cold meaning about 60F) and I got 11. 6 volts so the sensor is good and the KSB should click in. I started the truck with the KSB unplugged and it shakes and smokes the same amount. After warm up I made a jumper from battery positive to the KSB and tested it. There is no change in engine speed/sound with it connected. I am fairly certain I have a bad KSB solenoid. So how do I change it? Can I just unscrew it and screw a new one in or so I have to bleed the pump? What should I apply to the threads? Any info would help.