This is what my thermostat looked like when I replaced it.

[rizzjc]

Well, I should know better, but after 10 years, 136,000 miles, and an P0125 code, I decided it was finally time to replace my thermostat on my Explorer. This is what it looked like:

There was a time when I thought I was pretty good about maintenance on my truck. Now I shame myself for not doing the simple stuff sooner. I promise to be better.

 

[snocross1985]

Don't apologize to us, apologize to your poor truck.

 

[rizzjc]

She's payed me back with many a cracked nuckle over the years.

 

[BrooklynBay]

Just out of curiosity, did your old thermostat have a weep hole, or maybe it's called a bleeder hole?

 

[rizzjc]

Ummm, I'd have to say yes. Not sure, but I noticed this little piece mounted in the side of it which looked like it had a ball bearing in it. Would that be it? The new one did not have this. Why?

 

[BrooklynBay]

The ball is a spring loaded check ball. Did it have a spring?

 

[rizzjc]

Ummm, no. Now you're getting me worried. What's it "checking"?

 

[BrooklynBay]

It's nothing to worry about. Some thermostats have that hole to allow extra coolant to flow while its in the closed position. The ball is there to allow coolant to flow in one direction, and block any reverse flow.

 

[BrooklynBay]

Check this thread: http://www.explorerforum.com/forums/showthread.php?t=162165. It talks about the hole in the thermostat. Here is the link to my 10 steps to a clean cooling system thread: http://www.explorerforum.com/forums/showthread.php?t=162848

 

[rizzjc]

Yeah, I asked my buddy and he said that there may be just the ball. I noticed that the new one did not have this. You had me worried, but all is good now ... as soon as I get the new bypass hose installed, and fire it up! I just replaced the fluid, and flushed it a short time ago, but I notice there is still a lot of sludge that didn't get flushed out, so it looks like I'll be doing it again soon. I guess the 5.0 has a drain plug in the block, so I'll have to find that that next time I flush it.

 

[BrooklynBay]

This link has some detailed diagrams on modifying thermostats: http://www.mgfcar.de/thermostat/

 

[Monkeysee62]

What's the easiest way to change this???

 

[BrooklynBay]

You have to remove the thermostat housing to replace the thermostat. Install a new gasket, and thermostat. Make sure that you refill the system with the proper level of coolant when you are finished. That is the whole procedure.

 

[ExplorerDMB]

Just be glad your thermostat didn't fall apart and go into your cooling system

-Drew

 

[rizzjc]

Yeah, that was good. Just another thing to add to the list of things to do to keep on top of maintenance, if I want this thing to go 200k!