Brrrrrrrrrrrr. My heat sucks! Opinions needed!

[Ghetto]

So....I have an 82 shortbox 2wd 250ci 6 cylinder. Last year I froze my ass off all winter. Since last winter the following have been replaced:

Heater Core
Heater Hoses
Upper Radiator Hose
Thermostat (192)
Heater Control Panel
Water Pump.

Now if you let the truck sit there and idle with the heat on it will warm up a little bit. The temp of the heat coming out is luke warm at best. When I first replaced all those parts it had decent temp blowing out. when you start driving the temp of the air coming out drops way down to barely warmer then the air inside the cab itself. Heater hoses are hot going into the core. No blockages anywhere. Lower radiator hose is usually always cold along with that entire side of the radiator as well.

Any ideas? I don't have any carpets or insulation. I assume adding that would help out a little but it's not going to change the air temp coming from the heater. Is it just old technology and parts so I should just bundle up and deal with it? I am ready to buy a modern 4wd truck for the winter months and hot summer days (no AC and vinyl bench is unbareable..)

Help!!!!!

 

[yevgenievich]

Hot/cold door and outside vs inside vacuum controlled doors might be at fault. What is your engine temp? There is a sticky with a lot of info nd pictures in this section

 

[Georgeb]

What does your temp gauge say? Does it stay up to operating temperature?

 

[crazy4offroad]

Has the block been flushed? Water/coolant ratio correct? Good door seals?

 

[Ghetto]

The engine runs at normal operating temps. Door seals are in good shape. There is a small draft towards the rear of the drivers door but can only be felt between the door and the seat. Regardless that doesn't effect the temp of the heat coming out. Its borderline cold blowing out.

As far as vacuum operated doors etc I do not have any vacuum operated anything in my heater box. Period.

 

[Ghetto]

Block has been flushed and correct ratio and amount of coolant present.

 

[bucket]

Something isn't right. Maybe a loose blend door and air movement going down the road makes it open up?

I had a heat-only '79 with the 250, it was one of the best heaters I've had in a truck.

 

[Georgeb]

I wonder if the blend door in the heater is fuctioning proprly.

 

[bucket]

And do the lower side vents fully close?

 

[Ghetto]

Lower side vents do fully close..nothing coming from there. When I had the heater box out to do the heater core I made sure everything was in working order and as far as I could tell everything was in fact functional. When you move the heater control to cold the air temp gets ice cold and warms up a little to luke warm when you move it to full hot.

 

[crazy4offroad]

When the truck is fully warm, feel the heater hoses. If they are hot or not will point you where to look, inside the cab or inside the engine. It seems like it may need a hotter thermostat or lean out the idle air to put some heat in it. Should be able to pull the idle down just 50-150 rpm using idle air adjustment to lean out the carb a little, then bump the idle back up. It will make the plugs run cleaner.

 

[Mr Clean]

Do you have both of your heater hoses running to the correct locations? IE the lower one to the radiator, and the upper one running to the block, and not the water pump? Sounds like to me, your truck is running fine, you just aren't getting the hot water into the cab.

 

[Ghetto]

Hoses are hooked up correctly and hot. Triple checking that the blend door is operating as it should be in a few mins. 98% sure it is

 

[89Suburban]

Block off 3/4 of the grille surface with a piece of cardboard or plastic and see what happens. I have a piece of clear plexiglass I use. Every winter I put that on and tape the door vent's shut in the bottoms of the doors and it helps alot.

 

[Georgeb]

Block off 3/4 of the grille surface with a piece of cardboard or plastic and see what happens. I have a piece of clear plexiglass I use. Every winter I put that on and tape the door vent's shut in the bottoms of the doors and it helps alot.

This is good advice. I deleted the door vents in mine. I also use cardboard as a radiator cover when its really cold. My ecperience with straight sixes is that they don't heat real well to begin with.