How to: Replace a thermostat on a 1996 4.0L OHV V6.

[GRNMACHINE]

Just removed thermostat. The "Superstat" doesnt look right. It doesnt have a "bleeder" hole either. Went to stant website and it lists different part no. as well. Going to purchase a Motorcraft from Ford tomorrow. Lasted 13 years so going to spend the extra money and get a Motorcraft. Original was made in Germany.

 

[GRNMACHINE]

Great writeup, replaced it with OEM Ford T-stat. Went great. Also used Peak Global Lifetime anti freeze.

 

[96eb96]

Great writeup, replaced it with OEM Ford T-stat. Went great. Also used Peak Global Lifetime anti freeze.

The Motorcraft one is worth the money here. You can find it online and save a few bucks, worth even the $20 or so at the dealer. I was told it was specifically engineered for the 4.0L OHV making it very difficult to completely stick closed due to the ball valve and other features. The vast majority of failures are that of an open nature, with no damage to the engine.

 

[Gator Jeff]

This was my first ever repair to my Explorer and how I found the forum. The biggest PITA is recovering and disposing of the old coolant. Mine stuck closed by the way. I'll also say that the paper gasket and RTV is the way I went I'm still trouble free..

 

[GRNMACHINE]

Couldnt agree more. I think the OEM is like $30 at the dealer, I think I paid $23. May be a little cheaper online but with $7 shipping might as well go to the dealer. Call around some discount parts and some do not. Not something I would want to do often even though it was fairly easy, OEM was the way to go for me. OEM t-stat was made in Germany also.

 

[96eb96]

This was my first ever repair to my Explorer and how I found the forum. The biggest PITA is recovering and disposing of the old coolant. Mine stuck closed by the way. I'll also say that the paper gasket and RTV is the way I went I'm still trouble free..

I was told by a ford field service engineer that a stuck factory stat on the OHV will allow enough coolant to flow thru the hole at low RPMs to keep the engine reasonably cool so you can limp home. If you use one without a hole, it will overheat at any rpm if it gets stuck. I don't know if this is true, but it seems to make sense.

 

[sethpdx]

Nice one!

 

[sethpdx]

Nice write up. What year/series is the bimmer?

 

[SubieHo]

Before you start, drain all of your coolant out of the car. This will make your life a lot easier down the road.

Unless you're also replacing the coolant, there's no need to drain it all out. If you're reusing the coolant, you need drain only 2 quarts (max. 4 quarts if you want to play it safe) or so to get the level below the thermostat and you're good to go.

But yes, it's a very simple job and very easy to do yourself.

BTW, I've used the rubber seal on many cars without any problems. I've never had one leak and there's no gasket material to clean off the sealing surfaces if you should ever need to replace it again.

 

[Charlie]

Nice write up. What year/series is the bimmer?

2000 540i6

 

[sethpdx]

2000 540i6

Very nice! I like the size of the 540

 

[beach]

Although I don't have a ohv V6 (V8) did you have any problems removing the t-stat bolts? I cannot get them to budge on the 5.0

 

[SpringRubber]

Thanks! Very helpful pics. I followed them for replacing the thermostat in my '98 XLT with the 4.0 OHV engine. A few things to note with that:

After you pry out the old t-stat, note the rectangular notch at the TOP of the recess in which the t-stat was sitting.

If the new thermostat has a bleed hole, it goes on top (that recess apparently allows movement of the bleed pin). Makes sense (to me) that a hole to bleed air would be on top.

Make sure you get the rubber "seal" that fits around the flange of the thermostat, which you then set together into the recess. There is no fiber gasket.

I bought my thermostat at Carquest, their model #32049 (it's manufactured by Stant), with the rubber seal and total was less than $9. First went to Advance Auto Parts and their book also recommended a higher quality Stant thermostat that didn't have a bleed hole, so maybe the alignment with that one doesn't matter. But that's just my guess.

 

[Ck_asdf]

Hello, not sure if this is the right thermostat, but would these instructions help me in getting my A/C working properly again? Currently, when A/C is turned on, the compressor cycles on, off, on, off ... every few seconds. My friend had checked my truck out and he said it likely needs a new thermostat.

My Explorer is a '95 XL, though I'm not sure if it's OHV or SOHC - how might I know? What do the acronyms mean?

My friend noticed that when he puts a wire between the positive lead of the battery and a wire on the compressor, the A/C starts working again, with the compressor being forced to stay on.

If this isn't the right thermostat or direction I should be heading, might you be able to point me the right way?

He had some thoughts of rigging it so that he would attach a wire from the ignition power, to a switch in the cabin, to the compressor, that way I can turn the compressor on or off when I want A/C, and in case I forget to turn it off when I leave the truck, it would turn itself off since it's controlled by the ignition power (and not directly via the battery).

 

[jrp267]

The ac is probably doing that because it is low on refrigerant. There is a pressure sensor and if the system is just low enough it will kick the compressor on but then the pressure drop from that cycle results in a kick out of the switch. Replace the stat and for those without the hole I just drill a 1/8 in hole been doin it for years with my other vehicles.The hole allows air to bleed through and enough coolant that if you get slush it will melt it instead of keep the stat closed until a hose blows off.

 

[Ck_asdf]

The ac is probably doing that because it is low on refrigerant.

You were right, it was just simply low on refrigerant. To get it to "charge," we had to hot-wire it like I mentioned earlier, pump in the freon, and then let go of the wire, and ta-da! I had working A/C! That was a month or so ago, and it's been working great!

I'm not sure what your note about drilling holes is about, but I don't think that applies here.

 

[jrp267]

Drilling a hole in the thermostat when they don't have the bleed hole. I think thermostats where the original topic of the thread.

 

[jpablogc]

failure safe Tstat

I got my tstat from Autozone, they had 2 different , so i bought the "failure safe" one: it will always stuck OPEN when broke. I installed a week ago, and its doing ok so far, and solved my low temp/lazy gauge issue. The tstat is made in israel,bi-metallic and doesnt look cheap.Price was OK.

 

[duggyd123]

guys i just replaced my tstat and now my truck blows cold air when the heat is on any ideas why

 

[MatthewAlan8]

guys i just replaced my tstat and now my truck blows cold air when the heat is on any ideas why

Is it stuck open?