Great. Thanks.

 

I was going to start a thread, but this one covers it:
2000 Excursion V10, I live in Idaho and the truck warms up really quickly in the winter, but doesn't get WARM. Heater blows lukewarm, hard to keep cab warm when it is 20 degrees out. Wouldn't melt snow off the wipers/windshield, temp on the gauge barely got over the line above "C" .
Both Napa and Rockauto list a 195 as being stock, so I bought one and put it in. What came out was a Motorcraft 185. WIth the 195 the truck gets HOT inside, gauge is finally where it looks normal. (Above the line.) But mileage just dropped from 8-9 to 6-7 and truck is gutless. I just towed a light trailer and the triuck was horrible, it used to tow trailers twice the weight with no problem. (I am overgeared, 36" tires.)
So based on info here, I found that the RT1147 is correct for my truck, regardless of what NAPA and Rockauto say.
I need to test my old 185 and see if, after 200K miles, it has degraded to a 160 or something, but I guess next step is a new 185.
Just interesting that a thermostat hotter than stock would hurt mileage and power THAT much. It really drove like it was down a couple of cylinders, as far as power feel.

 

Ok, just came back in from swapping out the thermostat. First off, the stat that was in the truck was a 185, stamped YCZE-8575-88. The stat I put in was a MotoRad from Canadian Tire part#14-4082-8. It is a 195 and was listed as the only one for the truck.

When I drained the top half of the rad and removed the upper rad hose, I noticed that a steady flow of coolant was pushing up through the stat, even though the engine was cold. This leads me to believe that the stat was stuck open.

The O-ring that came with the new stat sits around the edge of the stat, which made it too large to fit in the hole, so I ended up reusing the O-ring from the original stat, which fits on top of the stat. As well, the stat that was in the truck had the weep hole on the drivers side, so that is how I installed the new one.

Put it back together, and warmed it up. According to the scanguage2, the temp climbed to 202 before I felt the stat open and the rad hose get hot. I then took it for a short drive to the store and back and the temp fluctuated between 197 and 206. Didn't notice anything too different otherwise.

I was a little surprised at how much hotter it was running than the rated stat temp so when I got home, I removed the Lund Grill inserts that have been in there since I bought the truck. I was wondering if they were limiting how much air was flowing to the rad. Off to pick up my kids in a few so I'll see if that affects the temp.

 

I just had to explain to Napa how their catalog is wrong, they don't even have or make a 185 for my truck. I ordered the 180 and tested my old 185, it starts to open way early, likke 150, then hangs and opens the rest of the way at 170 or so, roughly. Big problem (I think) is that after it opens, it won't close again until 140 or cooler. I think it was opening, then coolant was cooling off, and stat wasn't closing to regulate temp, thus the cool temps and lack of heater output. The 195 is stupid hot at my heater vents, like melt stuff hot. I'll put the 180 in it in the morning, see if I can find a happy medium. Oh, and currently at 6 MPG with the 195 in it. Compared to 8-10 with the old 185. Same driving conditions.

 

So how hot is too hot when it comes to operating temperatures. Once it warms up now, it seems to run 197-206 doing 50km(30mph) through mild hills.

 

So, thought I would update this thread. Since installing the 195, the truck seems to run in the 204-209 range most of the time. A couple of weeks ago, we hauled the slide-in camper over a mountain pass on vacation and the truck ran way too hot. At one point, the temp spiked over 230 on the scanguage and I had to pull over and shut down for a while out of fear of doing damage. I'm sure this isn't normal. I am going to do a coolant flush and install a stock ford replacement stat. Only problem is that Ford canada wants a shade under $50 for it. Going to look online for a US source.

 

Man, you got taken for a ride there... 189 for a thermostat change ?
Hope they used vaseline...

 

No they would have charged extra for that.

 

Want to update this thread again. We are heading off on our end of summer vacation with the slide-in camper, and I don't want a repeat of the overheating issues from early July.

Tonight I drained the rad and flushed the system by removing the stat and using a garden hose flushed the from the top of the rad out the thermostat housing. Once the water ran clear, I re-drained it, re-installed the stat and filled with 50/50. I then ran the engine with the reservoir cap off, waiting for the stat to open. It didn't seem to open. The scanguage eventually showed north of 220 with the upper rad hose still cool to the touch so I shut it down. Heater was on and blowing cold, even at 220.

Any idea what is going on? Is it a simple air pocket? Is the thermostat stuck closed? Water pump?

Frustrated and stuck. Thanks.

 

Sounds like air in the system.

There will be residual water left in the system. Adding 50/50 mix with residual water in the system will dilute the mix and lower the boiling point and raise freezing point. Check the mix with a coolant tester. Drain some coolant out the petcock in the radiator to test, you will not get an accurate reading from the coolant in the degas bottle.

 

Funny you say that. I was laying in bed last night wondering the same thing. I will pick up a new stat and coolant tester today, as well as some more straight coolant.

How do I deal with the air pocket?

 

Best way is to use non-mixed coolant.
Calculate half of what the total system capacity is and add that to the cooling system. Top off with distilled water.

 

I always buy straight coolant because some water will always be left in the system and I'm not paying more than $1 for a gallon of distilled water. I just flushed the system with distilled water after flushing with the hose, drained the radiator and filled the degas bottle and radiator up with straight coolant. This brought me to a ratio around 45% coolant and 55% water. I eventually got the mix to around 55% coolant 45% water which got me good down to around -45 degrees F temp.

My truck had an air pocket and I warmed it up most of the way by driving a couple miles and then slowly opened the cap (with a rag) to the degas bottle with the engine running. The level went down as it sucked coolant in and got rid of the air pocket. Then I topped off the degas bottle. You also want the heater on hot when you do this to circulate coolant through the heater core.

This is also another method.

How To Bleed A Cooling System - Eric The Car Guy - YouTube

 

im usually at 185

 

engin off , disconnect slowly heater core hose just beside the alternator (passager side) and fill up slowly until you see the prestone coming out by that port on the intake, reconnect the heater core hose and start your engine ,let it warm up and touch the upper radiator hose ,if that hose dont become hot when the gauge indicate around 200 f recheck your thermostat.