Need some insight into Boiling Coolant hot engine 2003 2.3 4cyl Ford Ranger - Page 2

Soledad · #16 08-09-2017, 01:27 PM

Did you get your issue resolved 2003rangerDude?

GSF1200S · #17 08-24-2017, 06:34 PM

Quote:

Originally Posted by Harbor_Handed

What did your gauge register when this happened? Was the gauge visibly showing overheating?

Try spinning your fan by hand - the one that's attached to the pulley system. If it keeps spinning after letting off it, it's not properly doing its job cooling and it needs a new fan clutch.

I'm no expert but it *could* be a blown head gasket. Is the coolant level remaining consistent? Is there any oil in the coolant? Can you remove some oil (when truck is cool) and see if it's milky at all, like chocolate milk?

If you don't have any of those symptoms discussed above, then I would change the thermostat (IMO, preferably to a mechanical Motocraft one).

I had to do a lot of problem solving on my own cooling system and I finally got it to where it's functioning great, but I'm no expert.

+1 on switching to a mechanical thermostat- did that on my 02 and it drives much better than the electric one. I used a 2004 Motorcraft 195 thermostat and wired a 1500ohm 1/2 watt resistor between the wires that went to the electric thermostat (to trick the ECM into believing its there, and thus avoiding a CEL at startup).

Harbor_Handed, how do you like the Gates 180 degree thermostat? Im going to be changing my coolant soon and notice that my truck runs a little stronger when its cooler as well as pings if I run regular 87 octane. It doesnt ping on 93 so I'm thinking a 180 might make the difference (or it might not).

At the same time, I know these engines were designed to run a bit hotter and so I dont want looser clearances and such under normal operating conditions. Still tossing the idea around.

Harbor_Handed · #18 08-25-2017, 05:58 AM

Quote:

Originally Posted by GSF1200S

Harbor_Handed, how do you like the Gates 180 degree thermostat? Im going to be changing my coolant soon and notice that my truck runs a little stronger when its cooler as well as pings if I run regular 87 octane. It doesnt ping on 93 so I'm thinking a 180 might make the difference (or it might not).

At the same time, I know these engines were designed to run a bit hotter and so I dont want looser clearances and such under normal operating conditions. Still tossing the idea around.

I love my Gates 180* thermostat. I have nothing bad to say about it. I don't run any monitoring software so I can't say what temps my engine gets up to or if it still eventually gets up to the same temps it would with a 190* thermostat, but I'm sure it takes longer to reach full temp with a lower temp thermostat. With my Gates thermostat, my temp gauge needle stays put right where it should be and never wavers. I'm very pleased with it.

GSF1200S · #19 08-25-2017, 09:43 AM

Quote:

Originally Posted by Harbor_Handed

I love my Gates 180* thermostat. I have nothing bad to say about it. I don't run any monitoring software so I can't say what temps my engine gets up to or if it still eventually gets up to the same temps it would with a 190* thermostat, but I'm sure it takes longer to reach full temp with a lower temp thermostat. With my Gates thermostat, my temp gauge needle stays put right where it should be and never wavers. I'm very pleased with it.

Just FYI: when a thermostat is closed, its closed. Whether its a 208 degree thermostat or a 180 degree thermostat, it will warm the engine up at the same rate because the thermostat isnt allowing flow from the radiator through the engine.

The degree setting of a thermostat dictates the operating temperature of the engine. A 180 degree thermostat will begin to open at 180 degrees to try and hold the engine close to that temperature. A 208 degree thermostat will begin to open at 208 degrees to try and hold the engine at that temperature.

The gates thermostat you got will not slow down the engine warming up- it just wont let the engine run as hot as the 195 degree thermostat of the 2004+ 2.3l rangers.

I asked about the 180 degree thermostat because I want to know if you notice any change in performance or driveability when its completely warmed up. Mine pings only when completely warmed up on 87 octane (and only under load), but not on 93 octane. I've changed the knock sensor, the fuel pump, verified fuel trims, changed plugs wires and coil pack etc all in the course of 100k mile maintenance, so I dont know whats causing it. But I'm thinking a 180 degree thermostat might make all the difference. If nothing else it might let me run midgrade without pinging. Beyond that I need to replace the MAP, MAF, and have the camshaft position sensor verified for position at the ford dealer (all of which would be pretty expensive even doing the first two myself).

dvrich · #20 08-25-2017, 01:17 PM

Quote:

Originally Posted by GSF1200S

+1 on switching to a mechanical thermostat- did that on my 02 and it drives much better than the electric one. I used a 2004 Motorcraft 195 thermostat and wired a 1500ohm 1/2 watt resistor between the wires that went to the electric thermostat (to trick the ECM into believing its there, and thus avoiding a CEL at startup).

Harbor_Handed, how do you like the Gates 180 degree thermostat? Im going to be changing my coolant soon and notice that my truck runs a little stronger when its cooler as well as pings if I run regular 87 octane. It doesnt ping on 93 so I'm thinking a 180 might make the difference (or it might not).

At the same time, I know these engines were designed to run a bit hotter and so I dont want looser clearances and such under normal operating conditions. Still tossing the idea around.

When I found out the Tstat temp rating in my 07 I thought
I was in the Twilight Zone. LOL

Harbor_Handed · #21 08-26-2017, 06:33 AM

Quote:

Originally Posted by GSF1200S

Just FYI: when a thermostat is closed, its closed. Whether its a 208 degree thermostat or a 180 degree thermostat, it will warm the engine up at the same rate because the thermostat isnt allowing flow from the radiator through the engine.

The degree setting of a thermostat dictates the operating temperature of the engine. A 180 degree thermostat will begin to open at 180 degrees to try and hold the engine close to that temperature. A 208 degree thermostat will begin to open at 208 degrees to try and hold the engine at that temperature.

The gates thermostat you got will not slow down the engine warming up- it just wont let the engine run as hot as the 195 degree thermostat of the 2004+ 2.3l rangers.

I asked about the 180 degree thermostat because I want to know if you notice any change in performance or driveability when its completely warmed up. Mine pings only when completely warmed up on 87 octane (and only under load), but not on 93 octane. I've changed the knock sensor, the fuel pump, verified fuel trims, changed plugs wires and coil pack etc all in the course of 100k mile maintenance, so I dont know whats causing it. But I'm thinking a 180 degree thermostat might make all the difference. If nothing else it might let me run midgrade without pinging. Beyond that I need to replace the MAP, MAF, and have the camshaft position sensor verified for position at the ford dealer (all of which would be pretty expensive even doing the first two myself).

A 180 will slow the engine warming up to its ultimate temperature by allowing the coolant to start flowing sooner than a 190.

There's a misconception that a thermostat maintains a more or less constant engine temperature that is its stated degree rating, but I found out in my own researches that this is not true. The main function of the thermostat is to get the engine warmed up to the proper temperature on cold days by blocking the flow of coolant until the indicated temperature is reached. Thermostats only regulate the minimum temperature of the engine but do not maintain a maximum temperature. Engines run significantly hotter than the degree rating of the thermostat.

"The biggest misunderstanding about thermostats is that people believe they make the engine run cooler. They don't necessarily do that. The cooling system and load on the engine determines how hot the engine gets, the thermostat fully open will still be the mercy of the coolant system's ability to remove heat.....The thermostat can only determine when the cooling system is allowed to start cooling the engine. It sets a floor, not a ceiling on engine temperatures."

http://www.tuneruniversity.com/blog/...the-advantage/

This is an interesting thread on thermostats and what they do and don't do, and there's a VERY informative interview with a Stant/Gates thermostat engineer in this thread.

https://www.jalopyjournal.com/forum/...mation.511046/

The general consensus that I found was that a low-temp thermostat will not keep the the engine at a significantly cooler temperature, and if that's what you're trying to do you'd be better served by optimizing your radiator (its ability to remove heat from the coolant/water) and fans.

Soledad · #22 08-26-2017, 08:15 AM

Quote:

Originally Posted by GSF1200S

I'm going to be changing my coolant soon and notice that my truck runs a little stronger when its cooler...

Mine acts the same exact way. It definitely runs stronger when the engine is warming up (open loop) vs. when the engine is completely warmed up (closed loop). I want that "power" all the time and not just for the few minutes the engine is warming up.

I know there is a company (forget the name, maybe Mishimoto??) that makes a nice aluminum radiator for our trucks. I've toyed with the idea of putting one of those in to see how it does. Probably could also as a test turn on the electric fan full time and see if that has any effect.

GSF1200S · #23 08-26-2017, 10:24 AM

Quote:

Originally Posted by Harbor_Handed

A 180 will slow the engine warming up to its ultimate temperature by allowing the coolant to start flowing sooner than a 190.

There's a misconception that a thermostat maintains a more or less constant engine temperature that is its stated degree rating, but I found out in my own researches that this is not true. The main function of the thermostat is to get the engine warmed up to the proper temperature on cold days by blocking the flow of coolant until the indicated temperature is reached. Thermostats only regulate the minimum temperature of the engine but do not maintain a maximum temperature. Engines run significantly hotter than the degree rating of the thermostat.

"The biggest misunderstanding about thermostats is that people believe they make the engine run cooler. They don't necessarily do that. The cooling system and load on the engine determines how hot the engine gets, the thermostat fully open will still be the mercy of the coolant system's ability to remove heat.....The thermostat can only determine when the cooling system is allowed to start cooling the engine. It sets a floor, not a ceiling on engine temperatures."

http://www.tuneruniversity.com/blog/...the-advantage/

This is an interesting thread on thermostats and what they do and don't do, and there's a VERY informative interview with a Stant/Gates thermostat engineer in this thread.

https://www.jalopyjournal.com/forum/...mation.511046/

The general consensus that I found was that a low-temp thermostat will not keep the the engine at a significantly cooler temperature, and if that's what you're trying to do you'd be better served by optimizing your radiator (its ability to remove heat from the coolant/water) and fans.

Good links and I'll have to do more reading on this.

I will say in your second link someone mentioned what I think might apply to our trucks at least some of the time: theoretically its true, but functionally it can set the engines operating temperature if the cooling system has far more cooling capacity than the engines capacity to generate heat.

The cooling system on our Rangers is pretty ridiculous- the radiator is massive and the coolant capacity is high compared to the amount of heat a 2.3l 4 banger can generate.

That said, you could still be right. My truck's ECM unfortunately doesnt pipe out engine coolant temperature via OBD2- just Cylinder Head Temperature. I do notice depending on load of course a fluctuation in temperature. I will say however that the electric thermostat saw CHT regularly go up into the 270 approaching 280 range, where now the worst it will get is 260 if I'm in 3rd accelerating up a steep hill (before with the electric it was at its worst cruising steady). For the shift to a mechanical 195 thermostat to make such a difference compared to the 208/195 electric thermostat even under load conditions suggests that the thermostat does regulate engine temperature at least somewhat, right? Again though, it does fluctuate so certainly you have a point.

I have a question though: if the cooling system determines the operating temperature entirely and the thermostat only really controls the minimum temperature (or the rate at which the engine warms up from the minimum temperature to the operating temperature designated by the capacity of the cooling system), why are you using a 180 degree thermostat in the first place?

Given that an engine wears less once warmed up due to expansion, it would seem IF the thermostat doesnt set the operating temperature, all you'd be doing is increasing engine wear by prolonging the warm up period. Right?

Honest questions- I'm open to being wrong about any of this. I think part of my issue is that I learned on older cars where the cooling systems were just DAMN large compared to the engine's capacity to generate heat...

**LATE EDIT** I have another question: if the thermostat doesnt control operating temperature on our trucks but rather just the radiator's capacity to cool the coolant, why did Ford put an electric thermostat in the truck in the first place?

Harbor_Handed · #24 08-27-2017, 10:17 AM

GSF1200S, I'm definitely no expert on thermostats, I'm not sure why Ford put that awful electric-assisted thermostat in but I do know that on hot days while idling in traffic with AC on, I'd see my temp needle start to creep up slightly which made me very nervous. Now it never does that, I'm very happy I got the electric t-stat out of there.

You asked why I put in a 180F thermostat: I have an intermittent knock that manifests only when fully warmed up and at the hottest temps. Like many, I thought a 10 degree lower thermostat would consistently keep the engine 10 degrees cooler, and thus it might not heat up to the point where it starts knocking. But when I put the 180F thermostat in, it would still knock although it took longer to start knocking and maybe decreased in frequency a little bit. I then thought "I need to get a 170F thermostat in there, that'll stop it from knocking for sure!" That was when I started doing research on low temp thermostats and when I discovered that thermostats don't really put a cap on engine temps like I thought.

I figured out that my knock is almost certainly the timing chain knocking due to a tensioner that weakens under high heat. It hasn't jumped a tooth or anything so I'm just ignoring the knock for now, but when I have $500 burning a hole in my pocket I'm going to take it in and have someone fix it.

And btw, I assume the lower temp t-stat probably does keep the engine a little bit cooler on average, but it's just not the fix that a lot of people hope it will be. I also thought about taking my truck to a tuner(?) & asking them to adjust the computer so the aux fan will come on 15 degrees cooler.

GSF1200S · #25 08-27-2017, 12:54 PM

Quote:

Originally Posted by Harbor_Handed

GSF1200S, I'm definitely no expert on thermostats, I'm not sure why Ford put that awful electric-assisted thermostat in but I do know that on hot days while idling in traffic with AC on, I'd see my temp needle start to creep up slightly which made me very nervous. Now it never does that, I'm very happy I got the electric t-stat out of there.

You asked why I put in a 180F thermostat: I have an intermittent knock that manifests only when fully warmed up and at the hottest temps. Like many, I thought a 10 degree lower thermostat would consistently keep the engine 10 degrees cooler, and thus it might not heat up to the point where it starts knocking. But when I put the 180F thermostat in, it would still knock although it took longer to start knocking and maybe decreased in frequency a little bit. I then thought "I need to get a 170F thermostat in there, that'll stop it from knocking for sure!" That was when I started doing research on low temp thermostats and when I discovered that thermostats don't really put a cap on engine temps like I thought.

I figured out that my knock is almost certainly the timing chain knocking due to a tensioner that weakens under high heat. It hasn't jumped a tooth or anything so I'm just ignoring the knock for now, but when I have $500 burning a hole in my pocket I'm going to take it in and have someone fix it.

And btw, I assume the lower temp t-stat probably does keep the engine a little bit cooler on average, but it's just not the fix that a lot of people hope it will be. I also thought about taking my truck to a tuner(?) & asking them to adjust the computer so the aux fan will come on 15 degrees cooler.

I see and fair enough. I too have an intermittent knock, but I think its the IMRC flaps in the intake manifold thats being amplified by the sound bouncing off the pavement beneath the truck. I cant hear mine with the hood open nor does it make any noise with a steth anywhere on the engine (even down by the crank or up a ways checking for piston slap or journal noise). I've been over every inch of the exhaust looking for an exhaust leak, but nothing (plus putting a load on like the A/C sees no change in volume or pitch of knock). I've been all over the timing cover with a steth and nothing there either. I can only hear it standing next to the truck on the drivers side, and its not always there. Oil viscosity makes no difference either. I know I've heard others mention this, so who knows- it hasnt changed prominence, pitch, or frequency in the 20k miles I've put on the truck, so I doubt its engine related.

I know in the research I did on the electric thermocrap they put on the Ranger I found many references to the electric portion being used to influence temperature under load conditions. The thermostat has power applied when entering FWOT conditions and such to cool the engine moreso and thus to allow for more timing advance without knock. But again, what you say makes sense as well- I notice fluctuation and with a fixed 195 thermostat that must be the capacity of the cooling system to shed heat.

ANOTHER possibility though is the fan clutch- perhaps that is where the fluctuation comes in, but given that its a thermally operated fan clutch instead of a centrifugal type, that doesnt make a ton of sense either.

Like you, I'm not an expert with thermostats or cooling systems. At the very least we can both agree that the electric thermostat sucked. I had an issue with coolant bubbling out of the reservoir and I mean just barely- spots on the bottle NOT boiling over. Over time my coolant level would slowly lower, and I had situations with timing being fairly retarded due to temp creep in steady state conditions (verified while occuring with an UltraGauge). The fixed 195 motorcraft thermostat and resistor mod fixed both issues instantly. Take a look in the thread linking in my signature (thermostat w/ resistor mod) for my musings and the musings of others over what we learned about the system if you want to ache your brain some more. Bottom line is that none of us know for sure wtf Ford was thinking..

Harbor_Handed · #26 08-28-2017, 06:52 AM

Quote:

Originally Posted by GSF1200S

I see and fair enough. I too have an intermittent knock, but I think its the IMRC flaps in the intake manifold thats being amplified by the sound bouncing off the pavement beneath the truck. I cant hear mine with the hood open nor does it make any noise with a steth anywhere on the engine (even down by the crank or up a ways checking for piston slap or journal noise). I've been over every inch of the exhaust looking for an exhaust leak, but nothing (plus putting a load on like the A/C sees no change in volume or pitch of knock). I've been all over the timing cover with a steth and nothing there either. I can only hear it standing next to the truck on the drivers side, and its not always there. Oil viscosity makes no difference either. I know I've heard others mention this, so who knows- it hasnt changed prominence, pitch, or frequency in the 20k miles I've put on the truck, so I doubt its engine related.

I know in the research I did on the electric thermocrap they put on the Ranger I found many references to the electric portion being used to influence temperature under load conditions. The thermostat has power applied when entering FWOT conditions and such to cool the engine moreso and thus to allow for more timing advance without knock. But again, what you say makes sense as well- I notice fluctuation and with a fixed 195 thermostat that must be the capacity of the cooling system to shed heat.

ANOTHER possibility though is the fan clutch- perhaps that is where the fluctuation comes in, but given that its a thermally operated fan clutch instead of a centrifugal type, that doesnt make a ton of sense either.

Like you, I'm not an expert with thermostats or cooling systems. At the very least we can both agree that the electric thermostat sucked. I had an issue with coolant bubbling out of the reservoir and I mean just barely- spots on the bottle NOT boiling over. Over time my coolant level would slowly lower, and I had situations with timing being fairly retarded due to temp creep in steady state conditions (verified while occuring with an UltraGauge). The fixed 195 motorcraft thermostat and resistor mod fixed both issues instantly. Take a look in the thread linking in my signature (thermostat w/ resistor mod) for my musings and the musings of others over what we learned about the system if you want to ache your brain some more. Bottom line is that none of us know for sure wtf Ford was thinking..

Thanks for the info.

Yes, my IMRC flaps started knocking soon after I bought my truck last November - kind of a fluttering knock that started right at startup - and so I replaced my whole intake manifold.

Hope you get your pinging issue figured out, there are lots of informative pages dealing with detonation and pre-ignition. The Gates 180F might be worth a try, because I suspect it does keep it a tad bit cooler consistently in there.