Still can't get any heat! Grrrrrrrrr

[Heavensup]

Still can't get heat!

We have a 1999 ford ranger 3.0L engine
2 wheel drive manual transmission.

We can't seem to get heat.
Here are the steps I've taken so far!

We have had no heat since last winter. It just stopped one day...

I have replaced the thermostat

I have replaced the water pump

I have replaced the heater control valve and it is in the open position

I have flushed the whole system

I have flushed the heater core separately using a garden hose and there was decent flow.

I have tested the blend door and it works. I was able to swivel the door with my hand when the actuator was removed.

I have tested blend door actuator and i can c it moving and took it apart and the gears are not stripped

Heater control is working as it moves the actuator when the switch is turned

The rop rad hose gets nice and hot i can hardly touch it. What the heck is the problem?? I have run out of ideas???????

 

[adsm08]

Do your heater hoses get as hot as the upper rad hose?

 

[kimcrwbr1]

Pull the heater hoses off of the engine and see if one or both of the fittings are plugged on the engine? Do you get good flow through the heater core with a garden hose going both directions?

 

[kimcrwbr1]

On my 2.8 the fitting on the thermostat housing was almost completely plugged with rust. I had to pull the waterpump and flush out the block in order to get the coolant green again.

 

[Heavensup]

Do your heater hoses get as hot as the upper rad hose?

No it dosen't and i have flushed it i used the garden hose do it. The stream was acceptable. I ran it till the water ran clear. Should i just replace that too??

 

[Heavensup]

Pull the heater hoses off of the engine and see if one or both of the fittings are plugged on the engine? Do you get good flow through the heater core with a garden hose going both directions?

When i flushed it i only went one way. But the flow was fine. I flushed with a garden hose.

 

[Heavensup]

On my 2.8 the fitting on the thermostat housing was almost completely plugged with rust. I had to pull the waterpump and flush out the block in order to get the coolant green again.

I flushed the whole system and replaced the thermostat and flushed the heater core separately. We have a new waterpump i installed that last week! We should have heat!!

 

[RonD]

When i flushed it i only went one way. But the flow was fine. I flushed with a garden hose.

The upper passage in the core can flow fine, but you won't get heat in the cab if just the upper passages are flowing.

Picture of heater core here: https://contentinfo.autozone.com/znetcs/product-info/en/US/prc/90010/image/2/

The middle and lower areas need good flow or there is no heat to transfer to the air blowing thru the core.

As said, after engine is warmed up, turn knob to cold and fan off
Feel both heater hoses at the firewall
Both should be same temp, IN hose may be slightly hotter than OUT hose

Now turn knob to HOT and Fan to High
OUT hose should now be getting cooler as heat is lost by the air flow thru the core.
If one hose isn't getting cooler then there is no heat transfer, no flow of coolant in middle or lower core

 

[Heavensup]

The upper passage in the core can flow fine, but you won't get heat in the cab if just the upper passages are flowing.

Picture of heater core here: https://contentinfo.autozone.com/znetcs/product-info/en/US/prc/90010/image/2/

The middle and lower areas need good flow or there is no heat to transfer to the air blowing thru the core.

As said, after engine is warmed up, turn knob to cold and fan off
Feel both heater hoses at the firewall
Both should be same temp, IN hose may be slightly hotter than OUT hose

Now turn knob to HOT and Fan to High
OUT hose should now be getting cooler as heat is lost by the air flow thru the core.
If one hose isn't getting cooler then there is no heat transfer, no flow of coolant in middle or lower core

Ok, i will check this out tomorrow and report back!! Thank u for helping me

 

[Heavensup]

Ok, i will check this out tomorrow and report back!! Thank u for helping me

Only one side of the heater hoses was warm and the other was cold. So ur correct, there is very limited flow... I will try back flushing tomorrow. I picked up what i need to do a better job flushing the heater core.... i also source a new heater core and have been looking up how to replace it, as if flushing doesn't work I will replace it! *sigh*