No heat, I've done everything

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curleywon

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I have no heat front or rear. Today I back flushed the entire cooling system with the kit which I installed in 2013 when I replaced the front heater core and radiator. I saw some rusted metal coming out but not enough to indicate a major blockage. I cut a hole behind the glove box to insure that the blend door is functioning properly. After filling the system, I still have no heat. Neither of the hoses going to the core are even warm and neither is the core itself when I touch it from the inside through the hole that I cut. I replaced the thermostat also. What am I missing? I also used a shop vac to blow as much water out of the system as possible before refilling. It only took 3 quarts to fill. I need help. I need heat.
 

Russell Lewis

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Get ones of these

OEMTOOLS 24506 Cooling System Back Flush Tool

Or similar.

There is a block on the heater core. You can flush then back flush if there is no heat on inlet then there is a block not allowing water to pass threw the core

Do both hoes get warm top and bottom of your radiator hoses showing Coolent circulating in radiator ?
 
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curleywon

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engine temps normal? did u have heat at any point?
Engine temperature is normal. Truck was overheating at idle until I changed the thermostat. Has good heat front and rear last winter and into the spring on a few chilly days. No white smoke or antifreeze smell from the exhaust to indicate a blown head gasket. I can't get the quick connects off to do a direct heater core flush.
 

98eb5.4

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should be able to flush the core just cutting the lines ~ 5-6" back?

u can also buy/rent/borrow the special tool but i found that a pia,

saw a good u tube vid showing back-flushing that seemed the better way to go

think i read where a worn water pump wasn't pumping enuff to get heat but otherwise was ok
 

Russell Lewis

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Might need a water pump.

Parts places rent “ fan tool “
I used 1 1/2 wrench and the belt to hold tight. In a pinch quick fix. Check amazon with a few brands compare to rock auto for price winner is the cheapest.
 

muskytom

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I have the same problem as curleywon - little to no heat front or rear and engine temp gauge normal/rises to and stays at the same position once warmed up. No overheat problem summer or winter. Was better last winter when I had a cooling system flush, but when temp got into low 20's and below, I started to notice it. At near and below zero, had to wear coveralls when -1 degrees driving from Chicago to Green Bay last week! Thermostat OK, coolant level OK, but heater core leak recently and "patched" with stop leak successfully. No change in heat but stopped the leak. Duct controls working OK. Any thoughts about heater control valve (can't seem to locate)?

At my wit's end. A friend mentioned to me that when he was a mechanic back in the early `70's, he encountered a no heat problem on a V-8 and referred to it as an "air-block" problem: air in the cooling system (but doesn't recall how he resolved it.)

Any ideas Group?
 

Adieu

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I have the same problem as curleywon - little to no heat front or rear and engine temp gauge normal/rises to and stays at the same position once warmed up. No overheat problem summer or winter. Was better last winter when I had a cooling system flush, but when temp got into low 20's and below, I started to notice it. At near and below zero, had to wear coveralls when -1 degrees driving from Chicago to Green Bay last week! Thermostat OK, coolant level OK, but heater core leak recently and "patched" with stop leak successfully. No change in heat but stopped the leak. Duct controls working OK. Any thoughts about heater control valve (can't seem to locate)?

At my wit's end. A friend mentioned to me that when he was a mechanic back in the early `70's, he encountered a no heat problem on a V-8 and referred to it as an "air-block" problem: air in the cooling system (but doesn't recall how he resolved it.)

Any ideas Group?

Yeah you have idle the engine with the radiator cap off for a while, multiple times, and top off the coolant.

You can have several liters' worth of air bubbles.

Also....are you sure your temperature control isn't messed up? I mean the dials/buttons themselves
 

muskytom

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The level in the fill bucket/overflow rises and lowers between hot & cold fill lines appropriately. I did have to add coolant, but don't recall if the engine was running - good point; I'll try that again.

Controls work fine: vent controls, fan speed and temperature runs the whole range from hot to cold - I feel it. Tried that almost immediately to rule out any binding or vacuum problems.
 

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