Active Shutters Causing Elevated Temps?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

SmokieRiver

Active Member
Joined
May 10, 2019
Posts
54
Reaction score
13
Location
SE WI
Some background:
My 2019 is my daily driver and doubles as a tow vehicle for my boat in the summer months. All summer I never had an issue with elevated engine temps. Even on a 5 hour tow in mid 90s outside temp the engine never showed an elevated temp, even with some moderate grade climbs. Late in the summer I had my cam phasers replaced (cab off). On my tow to the dealer for winterization and storage in mid-Oct, which was a 60 degree outside temperature day, I got the values above the engine temp indicator for a very short period of time while climbing a minor grade, but never had over temp and reduced power. I backed off the throttle and and temp came back to the normal range.

It’s been on and off annoying me since that happened and over the weekend it hit me to look at the engine shutters. I looked at them yesterday after a drive and they were only partly open. This morning before leaving for work on a cold start (just after start), engine not at operating temp, and they were partly open (not the best pic attached).

Is this normal to be partly open? I always thought they were fully open or full closed.
 

Attachments

  • 0F3ABBE7-8682-4B92-ABB8-1F72265F2497.jpeg
    0F3ABBE7-8682-4B92-ABB8-1F72265F2497.jpeg
    75.5 KB · Views: 48

JohnyPython

FRF Addict
Joined
Oct 28, 2018
Posts
10,479
Reaction score
47,502
Location
Canada
From what I remember, the shutters can be in various degrees of open. Your pic looks familiar so should be normal. Cold start your truck from outside and I believe that the shutters go thru a start sequence.

What is interesting is that perhaps you have air in the cooling system. I’m thinking your cam phaser repair has something to do with your temps.
 
OP
OP
S

SmokieRiver

Active Member
Joined
May 10, 2019
Posts
54
Reaction score
13
Location
SE WI
Definitely a possibility I got an air bubble in the cooling system.

It was surprising to me with the engine not at operating temperature (still cold) that the shutter was not completely closed. I may clip a GoPro to the grill over the weekend and go for a drive to make sure they are moving and not stuck in a partially open position.
 

Sbags

Member
Joined
May 2, 2017
Posts
11
Reaction score
3
I've heard of tons of people with high coolant temps after the VCT repair. I experienced erratic and high coolant temps after the repair. I took my truck twice to the dealer for this issue after the VCT repair and their response was: it hasn't pulled any codes, so it's fine. And according to them, it was normal for the truck to regularly hit 230 degrees in 20 degree weather driving around town.

Because this all started after the cam phaser repair, I thought it was maybe an air bubble. I followed the Ford protocol for bleeding the coolant system twice to see if the dealership somehow left an air bubble in it. No help.

I decided to replace the thermostat myself. Perhaps it was all a coincidence and the thermostat was failing after five years. The fan was running 100% of the time I was driving, which didn't happen for the first four years I owned the truck.

I went with a 170 degree SPD performance thermostat. Engine runs perfect now at 185-205, even when in sport mode on a hot day with full throttle up at 15% hill. I've heard that these engines need to run hot, but having the two stage fan running in all conditions is not right, especially given I hadn't experienced that for the first four years of ownership.

I hope this helps but this issue plagued my truck for five months. The install only took 30 minutes.
 
OP
OP
S

SmokieRiver

Active Member
Joined
May 10, 2019
Posts
54
Reaction score
13
Location
SE WI
I've heard of tons of people with high coolant temps after the VCT repair. I experienced erratic and high coolant temps after the repair. I took my truck twice to the dealer for this issue after the VCT repair and their response was: it hasn't pulled any codes, so it's fine. And according to them, it was normal for the truck to regularly hit 230 degrees in 20 degree weather driving around town.

Because this all started after the cam phaser repair, I thought it was maybe an air bubble. I followed the Ford protocol for bleeding the coolant system twice to see if the dealership somehow left an air bubble in it. No help.

I decided to replace the thermostat myself. Perhaps it was all a coincidence and the thermostat was failing after five years. The fan was running 100% of the time I was driving, which didn't happen for the first four years I owned the truck.

I went with a 170 degree SPD performance thermostat. Engine runs perfect now at 185-205, even when in sport mode on a hot day with full throttle up at 15% hill. I've heard that these engines need to run hot, but having the two stage fan running in all conditions is not right, especially given I hadn't experienced that for the first four years of ownership.

I hope this helps but this issue plagued my truck for five months. The install only took 30 minutes.

That does help. Thank you.

Where did you find the procedure for bleeding coolant system? I’ve searched the web and YouTube and only found people’s way to do it, not the way Ford says to do it.

If that doesn’t work, I might go the route of replacing the thermostat.
 

Sbags

Member
Joined
May 2, 2017
Posts
11
Reaction score
3
I saw a Ford Tech explain it on YouTube but I can't find it anymore. Here is the Haynes procedure for doing it. They don't mention it in the video, but people also suggest doing it on an incline to help any air get out of the system, especially the heater core.

 
OP
OP
S

SmokieRiver

Active Member
Joined
May 10, 2019
Posts
54
Reaction score
13
Location
SE WI
Everything checks out on the truck, so I’m leaning towards replacing thermostat with the 170 degree SPD performance thermostat. My engine is stock and I don’t plan on getting a tune. Is there any downside to having the engine run cooler, especially in the colder winter of SE Wisconsin? Anyone know what the stock thermostat is set to?
 

KAH 24

Full Access Member
Joined
Aug 30, 2020
Posts
176
Reaction score
456
Location
McKinney, TX
Everything checks out on the truck, so I’m leaning towards replacing thermostat with the 170 degree SPD performance thermostat. My engine is stock and I don’t plan on getting a tune. Is there any downside to having the engine run cooler, especially in the colder winter of SE Wisconsin? Anyone know what the stock thermostat is set to?
@SmokieRiver

First thoughts: How are the external fins on your radiator, is your fan actuating properly, is it possible that the cooling system isn’t purged properly, or is there something going on with another system.

I say this as radiators/cooling systems are inexpensive vs. engines.

I have professionally witnessed damage (and at an escalated level,warranty denial) from engines running too cold over time—due to short trips as most folks drive the vast majority of the time.

If you are towing well within the OEM recommendations—the issue is the cooling system and the colder cap will cause more problems than it “solves” (facetiously).
—————-

If your truck is stock, and your radiator/cooling system is functioning properly—there is nothing to be gained by running a colder thermostat.

Internal combustion engines are very inefficient pumps as much of energy generated is lost in heat, which must be evacuated—which is factored in during system design.

The balancing act in optimal performance of a modern high output engine is managed by a lot of skilled engineering nerds—a term I embrace as a badge of honor.

No doubt that Ford Performance engineering factored the thermostat in when they designed the H.O. Ecoboost—as any modern OEM does with a factory performance motor.

Given the abysmally low volume cost of a thermostat for an OEM (regardless of temp)—I’d state from professional experience that your stock temp thermostat is ideal for your application.

You live in Wisconsin. Colder isn’t better for engines—and in many cases is worse if longevity is a priority.

I’d be more concerned about cooler weather as engines often don’t get up to temp on short drives (which is not good)—especially up north. Unless you want to juggle/swap out thermostats by season, I’d stay stock.

Note: The juggling of thermostats won’t address the priority of getting the engine up to optimal temperature under all conditions—including 100 degree weather and short trips.

If you are concerned about overheating—focus on the solving the problem regarding airflow/coolant flow/radiator heat shedding—any system variables impacting the cooling system.

Please don’t try a bandaid fix for an ecosystem.

Possibly the sellers/marketers of aftermarket colder thermostats will disagree.

Good luck in solving. As an enthusiast, I can appreciate the frustration at times.

EDIT: PMCS. Wash the radiator by spraying water on it to dislodge bugs, debris, and inspect the radiator fins for signs of damage. Radiators collect debris—use enough spray pressure to avoid damage to the radiator fins.
 
Last edited:

Reaper308

FRF Supporting Member
Supporting Member
Joined
Oct 11, 2020
Posts
531
Reaction score
686
Location
Texas
FYI, being that your engine is stock and being up north as mentioned above I would lean toward replacing your thermostat with something stock or close to stock and would go with the Go-Pro to check your radiator shutters to make sure operating properly. But remember this is worth exactly what your paying for right now, so just my 2 cents! Good luck and keep us posted.
 
Top