Chevrolet Repair: water pump problems, cylinder head gasket, blazer s10

Question
replaced the water pump in my 1983 chevy blazer s10. when we started it, it was hard to start and idle only if you have foot on gas.  drove it  a little ways and now white smoke pours out the tail pipe, but there is no sign of water in the oil.  what could be the possible problem

Answer
HI JANELLA, WELL THE NEWS IS NOT GOOD, DID THIS ENGINE OVER HEAT RECENTLY ?? OR HAVE YOU BEEN ADDING COOLANT TO THE SYSTEM OFTEN ??? WHEN YOU FILLED THE SYSTEM AFTER INSTALLING THE PUMP AND PUSHED COOLANT INTO THE COMBUSTION CHAMBER. [[THE WATERPUMP HAD NOTHING TO DO WITH THIS]] THIS IS A CLASSIC SIGN OF A INTERNAL COOLANT LEAK. DOES THIS WHITE SMOKE SMELL LIKE OLD FISH BY CHANCE ?? MORE THEN LIKELY THE CYLINDER HEAD GASKET OR GASKETS ARE BAD CAUSING THE COOLANT TO GET SUCKED INTO THE CUMBUSTION CHAMBER AND OUT THE EXHAUST SYSTEM..THIS WILL ALSO CAUSE THE ENG TO RUN BAD AND STALL.. THIS WILL NEED TO GET REPAIRED ASAP. YOU DO NOT WANT COOLANT IN THE ENGINE OIL,COOLANT AND ROD AND MAIN BEARINGS TO NOT GET ALONG TOGETHER...LET ME KNOW IF YOU NEED MORE INFO ON THIS,PLEASE WHEN YOU LEAVE THIS SITE WOULD YOU MIND RATING THIS ANSWER. THANK YOU,,, TOM..