i have an 87 toyota pickup, been having a few problems with heating, goes up to very top white line before hot then drops down to normal temp, and stays. replaced radiator cap and thermostat. no change. smokes thick white smoke on startup and for about 10 minutes and then stops, doesn't smell like anti freeze and inside pipe is dry. and water circulates through radiator properly sometimes, but others doesn't move at all, no matter what temp. and one heater hose is hot but the other stays just warm. it also blows water out of radiator and resivor, and into a jug thats rigged to the overflow hose. some say heater coil some say it may be head gasket seeping? dont know, runs smooth as heck and exhaust pipe is dry, what is wrong with this thing???

 

You might check the radiator hoses to see if they are collapsing or the water pump might be defective.

 

hoses are fine, and look practically brand new (got truck about 2 weeks ago). and was thinking about that, but were gone flush everything this weekend to see if its stopped up somewhere

 

The temp overshoot is the thermostat...you need an OEM two-stage unit. Also keep in mind that the water will not circulate when the thermostat is closed.

I would start by doing compression and leakdown tests.