Heater core/ water pump issue?

[bcnsucks]

to start off its a 94 B3000 5sp 4x4 with 126,000k on it. about 4 weeks ago i flushed the heater core and radiator because it was not producing any heat, it was real nasty, rust dirt etc. and the heat worked for about 2 days only sometimes... then stopped all together again. then about a week later the temps started fluctuating alot, going from ice cold to hot almost instantly after 10 or so mins of driving. last night however when driving home it blew the hose coming out the top of the water punp to the heater core.. so i gues i need a lil help where to start? is it easy to replace the thermostat on the 3.0? (ive only had it for about 4 mos). or where should i start.. im pickin up a manual tonight, i just need an idea where to start. any help id greatly appreciated

 

[trail B2]

Whats your temp gauge doing during this is it fluctuating.It kinda sounds like you got shit moving and catching in your heater core.Is the hose coming apart on the inside and plugging the heater core?That would explain why it failed is it all hard and brittle.I would flush it to make sure you get water through the heater core put new hoses where there worn.Start the motor watch the temp gauge and feel the heat to try to determine if they work together when it makes heat.You know another problem that will cause your symptoms is low on water and air pockets going through the heater core so make sure your water is staying topped off before you make the heat check.