The stock temp gauge ushally sits right in the middle, but 2 weeks ago it started sumthing funny and would fluxuate to about 80 percent up instead of like 50 and would sum times suddenly drop back to normal. Since its florida it wasnt cold at the time, then it got cold I tried to turn on the heat and it would not get hot. So I thought it was the heater vale the hose on the way to the heater core, I replaced it and still no heat the valve is working correctly. And the heater core is not leaking or clogged. All vaccum control lines are intact and i still have no heat anybody ever experience this?

 

Sound like your thermostat might be getting stuck

 

Sorry Forgot to mention this before, I just replaced it about 2 months ago.

 

Well.. it's either the t-stat or air thats trapped in the system.

Rich

 

could also be the water pump.

 

How would I go about getting all the air out of the system?

 

Why did you replace the T-stat 2 months ago? What kind of symptoms were you having then?

 

When I replaced it was sticking and the truck was overheating.

 

take the cap off (WHEN THE TRUCK IS COLD) and let it run. you can hold it at high idle for a second if you want (about 2000-3000rpm).
keep adding fluid as the air comes out.
it is normal that it will spew some out when the air comes out, so have a drain pan ready.

 

So the overflow resivor dosent at as a T-line to bleed the air out?

 

No Danial I'm afraid that's not true. If the impeller lost it's press fit to the bearing shaft it would stop all together.

(I was a water pump engineer for 5 years (no joke))

Rich

 

Thats a relief could the new thermostat be malfuncting or a clogged hose?

 

Who replaced the t-stat? Could the "new" one have been put in facing the wrong way?

Purging all the air out of the cooling system can take a while, but following the directions that have been given you should be able to do it.

Regarding waterpumps, IMO you can't really ever completely rule them out either (although I also doubt it's the WP in this case). For example, the '96-'99 Taurus 3.0L vulcan was prone to a condition called "brown coolant" which would often just eat away at the impeller fins.

 

i didn't say it was, i said it could be.

but i think its acting the way it is due to having air in the system.
i have seen a few people do work on cars and not bleed the coolant system.

 

I'm not trying to make you look bad but this sounds to me like the thermostadt might not be installed correctly and the sending unit is either bad or malfunctioning because of the thermostadt. I would recommend taking the thermo out again and double checking to make sure it's in there right and I only say that because I put mine in wrong even after looking at the instructions over and over. I realized I messed it up at the last second before I was about to drive it, then took it apart and put it in right. It almost sounds like the thermostadt is blocking the water flow and not allowing it to circulate to the heater core. This is just the idea I get from seeing what you posted.

 

I'm 100% positive the t-stat is in right its was over 3 months ago I changed it and this is a new problem. Also when i took it out it went back in facing exactly the same way as the old one so I think its fine.