I recently bought a 1995 Chevy K2500, 7.4L and drove to work. there was no heat coming out of the heater till i was on the highway doing 70 and as soon as I slowed down in town it got cold again. the temp gage stayed at about 190 the whole time. The water pump looks like it was replaced not long ago. I am wondering if the hoses are routed wrong. They currently go from the engine intake to the heater core then to the radiator. Is this wright or wrong? Any info would be helpfull.

 

Yes that's correct.
With the truck COLD. Start the truck and let it start to warm up with the rad cap off.
See if the new water pump is circulating. This also will confirm if the thermostat is stuck open.

Welcome to Truck Forums

 

Once the truck is up to running temp, put your hand on the heater hose and see if they are both hot and about the same temp.Than report back.

 

I'm voting thermostat here.

 

Sounds like the hoses are routed correctly. Do you hear the coolant rush into the heater core after you start it in the morning? My guess is plugged heater core.

Do what ItBeMe said - check the temperature of the heater hoses. They should have roughly the same temperature.

 

Well I am guessing Digger59 froze to death in his truck, that why he never got back to us.

 

 

Watched radiator and water did not circulate until it was hot. I'm going to pull the thermostat and see if it is the right one. Thank you for your help, sorry it took me so long to get back.

 

It wont circulate until the thermostat opens at temp.

Did you check the heater hoses at running temp.

 

Sounds like your thermostat is good and doing it's job.
If your not getting heat in the cab until your doing 70 ? It could be your water pump. It seems to circulate better at higher rpm