Overheating Question

Member ID
#7179
Messages
329
Likes
292
#1
Has anyone heard of this remedy before?

A mechanic I know was telling me that he owned a Focus ST, and in order to facilitate engine cooling, he removed the shutters on the cooling fan assembly.

Does anyone have a story to add? I'm wondering if I should also remove them as well...
 


Member ID
#19063
Messages
6
Likes
13
#2
I've never heard of that, but it seems easier and probably more effective to just put in an aftermarket thermostat for $50.
 


Intuit

4000 Post Club
Member ID
#4881
Messages
4,057
Likes
2,584
#3
I do vaguely recall noticing that some part of the system (fuse box?) had provisions for supporting an active grill shutter system, but I don't think that's something that was added to our vehicles.

I don't think that applies to us.
 


Member ID
#3074
Messages
251
Likes
156
#4
The shutters are there to help the running fan draw air through the radiator (front to back) when car is stationary. Maybe the mechanic was trying to improve cooling for a FoST that spends more time moving than stopped in traffic.
 


PhoenixM3

Senior Member
Member ID
#2485
Messages
806
Likes
510
#5
I've never heard of that, but it seems easier and probably more effective to just put in an aftermarket thermostat for $50.
To me replacing the thermostat was more painful than installing my S280. God, I hate those hose clamps.
 


Intuit

4000 Post Club
Member ID
#4881
Messages
4,057
Likes
2,584
#6
In short, an active grill shutter system allows the PCM / ECU to run the engine above thermostat open temperature.

If there was an easy way to achieve it, would've added an active grill shutter system to the motorcycle. It's older engine management technology that lacks an oxygen sensor in the exhaust meaning, it can't tweak A/F ratios on the fly. When the ratios are significantly off, it begins to fowl the plugs. A programmable grill shutter system would allow me the option to run it above thermostat temp, thereby keeping the plugs clean. As it is now, I've merely been running a step hotter plugs while blocking off 15% to 60% of the radiator until I complete my AFR gauge install. (nearly done just need the bung welded)

It's possible that higher compression direct injection engines may be a bit more prone to fowling issues; and there could be situations where the PCM will force the engine to run well above thermostat open temp. These systems were more common in high dollar performance and luxury vehicles.
 


Last edited:


Top