Thermostat replacement and not enough heat

[jojomanigbas]

My mechanic told me that my thermostat needs to be replaced.
The temperature always show cold even after the car has been running for hours. I know I need to get this fixed.
My question, could this be the reason why the car is blowing warm air instead of hot even when the dial is turned all the way to hot?
Does the two related in some way?

95 XLT 4.0L

Any advice is greatly appriciated.

-Jojo

 

[dmac0923]

he didnt fully "burp" the coolant system. you have a huge air pocket in the heater core and probably in the intake preventing the coolant temp senser from reading the coolant temp


just take the radiator cap off (WITH ENGINE COLD) and run the engine up to operating temp when the thermostat should open....

stand back cause coolant will be burping and shoot out all over

 

[toypaseo]

I am no mechanic, but I believe so.

When my parent's had my Explorer, I remember my Mom complaining how the heat never got hot during the last winter they had it. She also mentioned on how the temperature gauge never got above ¼.

Right before I got it, I had the thermostat replaced, along with a flush and fill of the radiator. Plenty of heat after that.

 

[dmac0923]

my mistake, i thought he replaced the thermostat and now you have the problems.

 

[dmac0923]

even with a thermostat stuck in the open postion the engine will eventually get to operating temp. you wont have heat for a long time, but the engine will get hot

 

[glfredrick]

I'd suggest looking in a couple of places...

1. The thermostat. It could be bad, and changing a thermostat is no big deal. Just a couple of bolts a gasket and a new thermostat. You don't really have to drain down the entire system to do the job. You won't loose all that much anti-freeze. Just remember to re-fill properly (engine running and up to operating temp).

2. A bubble as has already been suggested. The true cure for bubbles in the cooling system is to use a vacuum filler, but a lot of people don't have access to one of them. You might try parking your truck with the nose facing uphill so it can burp.

3. The valve that lets heat into the heater core, which can stick.

 

[jojomanigbas]

Thanks.... I will try the "burp" method before replacing the thermostat.

 

[glfredrick]

Thanks.... I will try the "burp" method before replacing the thermostat.

That's fine, but for the low cost of a new thermostat, I'd just replace it... They're under $10 at any parts store and as I said, you don't even have to drain your system. I clamp off the upper hose and swap it out when I do it. You'll generally loose less than a quart or so, and it will show you if there is actually anti-freeze in the engine block.


Oh, and don't fall into the trap of trying a cooler thermostat on the Explorer engine -- that will kill its performance in a big hurry... They need to run 195.

 

[BrooklynBay]

Check the heater core hoses. Both of them should be around the same temperature. Don't expect both of them to be exactly the same temperature. You lose a little heat because the heater core, and hoses release excess heat even without the blower motor being turned on.

 

[Explorer Buff]

My mechanic told me that my thermostat needs to be replaced.
The temperature always show cold even after the car has been running for hours. I know I need to get this fixed.
My question, could this be the reason why the car is blowing warm air instead of hot even when the dial is turned all the way to hot?
Does the two related in some way?

95 XLT 4.0L

Any advice is greatly appriciated.

-Jojo

So my issue where the gauge shows normal temperature but the air warms up normally to warm, then eventually gets cold shouldn't be an issue with the T-Stat or Heater Core (the hoses are hot)?

 

[BrooklynBay]

It can't be the heater core if it gets warm. It's probably the thermostat if it cools down too fast.