Hi guys, sorry about the lack of detail. It is a 2000 Ford XLT 2wd Ranger, 3.0L, 65,000 miles, auto.
The mechanic said he did a pressure check overnight and it was great. He replaced the cap, radiator and t-stat. Don't know what kind of t-stat yet, will call on Monday.

 

Just talked to my mechanic and he stated they DID NOT USE a Motorcraft t-stat. It was rated at 192 degrees and he doesn't know what kind it was. I am hoping this is all it needs.
Now i am thinking i will try and replace it myself. What do i do first? I think i know where it is, on top of the motor under the big hose, right?

 

Right. The housing is held in place with two bolts. Be sure to clean both surfaces and install with a new gasket.

Hope that solves your problem.

 

I am assuming i have to drain some anti-freeze from the bottom of the radiator til it drops below the top hose, right? Sorry for the noob questions but i never did this before. Also, today is freakin frigid here in SE Pa., gonna be numb when i am done this.

 

Hi Mayhem69,

Why don't you wait a day or two until it warms up outside. Your in the same cold weather pattern as I am. Its supposed to hit 25 degrees here today and even warmer tomorrow. I agree, it is still a miserable, cold job. Fortunately it shouldn't take too long.

According to the Ranger factory service manual modified:

1. Drain the coolant to below the thermostat opening. Use the drain at the bottom of the radiator. Catch as much of the coolant as you can in a pan and reuse it.

2. Disconnect the heater hose (the small one) from the thermostat housing. You can also disconnect the bigger hose that goes to the radiator, but it isn't necessary.

3. Remove the two bolts that retain the thermostat housing. Pull the housing away from the engine block.

4. Remove the thermostat, noting which end of it goes into the block.

5. Remove the gasket. Make sure both surfaces are clean.

Installation is the reverse of the removal.

Let's hope that solves the burping problem. If you need more help or directions, just ask. That's why we're here.

 

Ok, removed the old t-stat and noticed some silicone around the inside lip of the housing. I scraped everything clean, installed the new t-stat without silicone, gasket, and took her for a test run.
Same symptoms so far, fluctuating temp. needle, i did have some nice heat for a few minutes. Pulled up to my garage and popped the hood to have a look. I opened the resevoir tank and noticed a few bubbles in there. Went back inside the truck and it was blowing cold air again.
I parked her and went inside, this time the fluid did not push out the resevoir, so that is good.
May take some time to get the air out yet i guess?

 

With engine cold park on steep incline, remove rad cap ,turn heat on high start it up and run till fully warmed up. That should burp out your trapped air. Top off if necessary (level drops once trapped air escapes) replace cap and hopefully problem solved.

 

Your first sign that your mech was inept was the silicone on the thermostat. It is not needed, and can impede the stat from operating. Wonder if any got loose and wandered into the cooling system.
If you run the engine with the radiator cap removed, you may be surprised to see how much expansion can occur in just a few minutes. A possibly better way to 'burp' the system is to manipulate the large upper hose so as to force any bubbles of air into the radiator top tank. Do this by pushing the hose, near the thermostat, down, so the bubbles will want to go 'up' into the tank. Work your way forward towards the tank, each time making sure the bubbles will stay 'trapped' by keeping a depression on the hose. When you can squeeze the top hose, and see the coolant level in the tank go up and down as you squeeze and release, WITHOUT any gurgling of bubbles, you know you have pretty well gotten the air out of that part. To get the air out of the heater core hoses is more difficult. I used a Prestone flushing tee, using the garden hose adapter cap as a release point for any trapped air. Again, I worked the hoses so that any bubbles of air would want to go to the highest point, which I made the adapter become by raising it as much as I could. Then open the cap, and let the bubble out. If you can't do this, you can do similar by loosening one end of a heater core hose, and make it the high point for air to escape, then, when it is full of coolant, re-install it.
tom

 

Yes, i did try before taking off the cap to get the air out, but the coolant rises up too much, i couldn't do that. I will try what you suggest with the top hose. Thanks.

 

You do realize the cap has two positions right? It has a position where is is on, but loose. That on but loose position is designed to help burp the system.

 

I learn something everyday.....I obviously knew it had 2 potions but did not know that the loose one would help with burping

 

I have a 99 ranger and I had a few of the problems that you are describing. I had a blown intake gasket and it was causing a over pressure problem to. Pushing everything right back into the overflow tank.

 

I didn't know this, thanks i will try to get the air out in that position. This morning i was running around. It did the usual temp. fluctuation just a little bit, and then i had heat without losing it. We'll see i guess, hope it isn't the intake gasket like described abov. Thanks for everyone's help!

 

Did your mechanic ever do a compression check? Or pull the spark plugs for a visual inspection?