Thermostat chat, Ranger temp obsession (let's split some hairs)

[cbxer55]

YOU said the temp gauges run lower with the cooler thermostats, therefore you are not running them hard enough for the thermostat to be fully open - it's just how the mechanism works in that once the thermostat is wide open both are exactly the same.

As @scotts90ranger said, it isn't really possible to run them hard enough to tax the cooling system on public roads, except maybe if you are towing near capacity in the hills. The heat loss on short bursts is nothing compared to sustained output. Did you think you were the only mid-50's guy that knows how to run a vehicle hard? I learned how to heel-toe, double clutch and match revs 30yrs ago, and understand slip angles, the proper line through a curve and late braking. Like a lot of guys here I can run fast if I want to, and the Abarth gets workout quite often, but I also gained a little wisdom along the way and don't want to hurt anyone or piss people off at their homes either. Still, there is no way I could make that engine work up a sweat even at insane speeds on public roads.

The other condition where the thermostat may open fully is at long idle or stop & go traffic where there is not as much air flow.

I know all about proper lines through curves, one of my favorite past times is hauling ass around curvy roads. Yup, don't like pissing off the neighbors. And yep, we have traffic lights here you can take a nap at, I refer to them as nap-inducing stop lights. And hot and humid is the word of the day in Oklahoma. So I fully expect the thermostats on any of the five vehicles listed in my sig line are fully open at some point in time during the summer. During the winter, not so much. Al I have to do is turn the heater on in any one of them, and can watch the temp needle drop noticeably. I rarely run ac, I prefer driving with the windows down. Long highway use is the only exception.

 

[Eddo Rogue]

Ah ok. I believe all thermostats have a fail safe designed into them to fail in the open position.

I may be wrong in that but it makes sense to me that they would. Otherwise things could go very bad. Better to have the engine not get hot enough and over heat.

One thing to look at that many over look is the radiator cap. Those do fail but generally in a way that they won’t hold pressure and the engine will over heat.

There was a discussion not that long ago about people having a too high of a psi rating on their trucks as well. That can cause issues too. Usually, its an aftermarket cap but there have been some that were the cap that came from the factory.

It might be worth looking at that as well and see if you have the correct one. I can’t tell you which yours should have since they vary from engine to engine. Heck, I would have to look up what my trucks are supposed to have since I don’t have them committed to memory.

ah yes another can of worms...I noticed they offer a 16lb and a 13lb for my ranger...I tried looking it up and still couldn't determine whats oem calls for.

Like my thermostats, I have a collection of various (new) caps too...A 13 lb metal, 13lb plastic and same for 16lb...The 16lb plastic fits the tightest and is what I'm running at the moment.

 

[Eddo Rogue]

How would I tell which lb cap my truck likes? What are the signs my lbs is too high? So far I havent really noticed a difference between the 13lb and 16lb. I am currently running a plastic 16lb, because it seems to have the tightest seal.

I was gonna tackle the cap topic next once my thermostat was determined, but since were here....

 

[Eddo Rogue]

You have no idea how I run my Vehicles. What's the point of owning a much modified Lightning if you're not going to use it? What's the point in the modified exhaust, MAC intake and chip on the computer on my Ranger if I'm not going to thrash it like a rented mule? What's the point in the custom exhaust, WeaponR intake and 93 octane tune on my Mustang if I'm not going to beat it like a red-headed step-child? I may be 58 years old, but I still like to drive rather aggressively. Maybe too much so. I don't have a Suzuki B-King for no reason. And YES, I know how to ride it! LMAO!

I dont think he meant "you" specifically, but more like you as in whoever in general...Take it easy old man lol

 

[Dirtman]

If become a supporter can i kill idiot threads?

 

[sheep herder]

If become a supporter can i kill idiot threads?

No, you just have to start more idiot threads.

 

[Dirtman]

So true...

 

[sgtsandman]

How would I tell which lb cap my truck likes? What are the signs my lbs is too high? So far I havent really noticed a difference between the 13lb and 16lb. I am currently running a plastic 16lb, because it seems to have the tightest seal.

I was gonna tackle the cap topic next once my thermostat was determined, but since were here....

Best way to check that is to look up the cap on the ford parts side and see what they list. The psi rating should be listed. Rock Auto seems to be a pretty good reference to the most part too.

 

[gaz]

Eddo:

I ran 192° until I installed a Hypertech CHiP, which recommended a 160°. I tried the CHiP with the 192°, 185°, 180°, 170° and 160° each for several tanks while driving in Southern California and Arizona to see which yielded the highest fuel economy. The results were to use the 180° even though Hypertech suggested a 160°.

I now drive in a more temporate climate, 58-78°F and have still achieve the best fuel economy with a 180° with the CHiP. So if you don't want to fiddle around with it the 192° will work great, especially with stock computer fuel maps. Invest in better hoses instead.

Goodyear Hi-Miler (blue silicone/rubber)
Stainless Steel

 

[scotts90ranger]

Also when installing thermostats be sure to do it correctly... Two of my vehicles had thermostats installed incorrectly by the previous owner... on my '00 5.0L Explorer someone installed it BACKWARD since the thermostat housing had room for it to be backward, they installed it that way... when I got it the temperature cycled kinda weird then just acted like it was stuck open, turns out it was... Then on the '97 F350 7.3L someone put the thermostat on top of the gasket then siliconed the housing on, that thermostat has the spring loaded bypass that was now 1/8" higher than designed...

 

[RonD]

Cooling system pressure
Water boils at 212degF at sea level, at 5,000ft elevation(Denver) it boils at 203degF, so it changes with elevation

Boiling point of 50/50 mix of anti-freeze and water is 223degF, at sea level, its the anti-freeze part, the ethylene glycol, that does this, it also lowers the freezing point of 50/50 mix to -35degF

But even at 223degF an engine might boil over pulling a load or on a long uphill grade

So back to the sea level/Denver thing, at sea level there is about 15lbs of air pressure, in Denver about 12lbs, so boiling point goes down when pressure goes down, about 3deg per pound, so what happens if pressure goes UP?

So cooling system is pressurized to raise the boiling point of 50/50 mix, you get about 3degF per Pound of pressure
So 15lbs cap would add 45degF to boiling point of 50/50 mix, 223 + 45 = 268degF boiling point, now thats more like it
If an engine gets above 250deg something is WRONG

You can go with higher pressure but then you risk blowing off hoses and or gaskets, and there is no real gain because if engine is getting hotter than 250degF there is a problem, that's about 3/4 on a temp gauge

12lb cap is OK on some engines, thats 36degF more so, 223 + 36 = 259degF

Cooling system GETS its pressure from the 50/50 mix expanding as its heated, like ALL liquids do, thats how a pressure cooker works.
So the pressure is "free", nothing else is needed but a sealed system and a pressure relief valve(rad cap)

Most vehicles use a 14 to 16psi cap, this is strictly for the boiling point of the liquid used in the system.

Now you do lose 10degF on boiling point of any liquid when driving at higher elevations so using a lower pressure cap in Denver might not be the best idea

 

[Eddo Rogue]

Update: I installed a digital temp gauge with the sensor spliced up at the heater core hose going to the waterpump. With the 195F thermostat, my temps are between 192f and 198f. It stays in the 180s for awhile until fully warm, and will max out at 200F (rarely).

I may re-splice it into the upper or lower radiator hose for comparison.

So far it has shown me my factory gauge is not so sensitive.

Also shes running quite perfect and awesome, so Im probably not gonna mess w/ it for now, and just enjoy driving it a bit....

 

[Eddo Rogue]

Also I am running a 13lb cap. Also I revived this thread partially to piss off Dirtman

 

[JohnnyO]

I started off with a 160* thermostat per someone on here's recommendation for a V8 swap, the only thing it accomplished was pathetic heat in the winter. Engine still ran around 200* in the summer.

It now has a normal replacement 190-195 stat in it. No jiggler and hodge-podge system was a PITA to bleed so I drilled a 1/8" hole in it and it is now a breeze to fill.

That's the thing. If your engine is predisposed to run at say 205*, it doesn't matter if you have a 160*, 180*, or 195*, it's going to run at 205*.

 

[Dirtman]

I just don't understand why engines dont use liquid sodium for coolant...