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Do grille inserts affect airflow through the condenser and radiator?


Brian Alcorn

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Do the grill inserts affect airflow thru the condenser and radiator ...would it cause the ac to not work as well or the engine to overheat tia
 

Steel City 06

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Anything in front of the radiator will have an impact on airflow. Any impact on airflow will have an impact on heat transfer.

For the engine, it won't cause it to overheat in normal conditions. In extreme conditions, it will overheat sooner, if it ever does. (If the returning coolant is hotter, the thermostat simply opens and allows more coolant to flow. But once the thermostat is wide open, no additional coolant can flow, and thus overheating begins.)

For the A/C it would probably have a measurable but not noticeable impact. The faster the airflow, the more heat the AC can remove from the air.

Unless you live somewhere very hot or tow frequently, I don't think you'll notice a difference in either. Plenty of TJs run inserts. Winches, large lights on the bumper, and other accessories can all have the same impact.

Are you installing them for protection or for looks?
 
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Brian Alcorn

Brian Alcorn

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Well it's to cover the view of the radiator and keep possible debris from making a hole there in
 

Goatman

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Do you have inserts now and experiencing these problems or are you thinking of getting them and are worried? They will slow airflow, but as previously said they shouldn't be a problem unless you are already having cooling problems.
 

WDE

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I have grill inserts and have not had any heat management issues. I rarely run the AC since I keep the windows out when its warm enough, or drive my truck when it rains.
 

Tranz Zam

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I run inserts now and then, and haven't experienced and negative side effects.

If you like em, run em!
 

pagrey

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I have a winch and lights that block most of my grill and wheel regularly in Death Valley at temps well over 100, sometimes 120. No problems with a correctly operating cooling system. You probably don't want to run the A/C all the time and the fan roars like crazy and sucks power like you wouldn't believe but no problems.
 

Ericict

I don't proofread for your enjoyment.
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I have a winch and lights that block most of my grill and wheel regularly in Death Valley at temps well over 100, sometimes 120. No problems with a correctly operating cooling system. You probably don't want to run the A/C all the time and the fan roars like crazy and sucks power like you wouldn't believe but no problems.
What temps are you seeing on your gage? What temp thermostat do you have installed? I would suspect you are the extreme but is great info for the rest of us to use as a base line.
 

pagrey

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Did a little math because people like @Jerry Bransford often like to say grill inserts are some sort of issue.

For the not faint at heart here it is. If the fan is flowing 2200cfm through the stock grill that requires about 0.2 psi of pressure drop. If you reduce the grill openings from 2" to 1.5" with the same fan speed you will reduce that flow to 1500 cfm. As the temperature increases the fan now spins faster. To increase the flow back to 2200cfm requires 0.5 psi drop total which takes about 50W or 0.07HP extra. This is the extra work required from your 190HP engine to make up for closing your grill up 1/2".

1/10 HP

Feel free to crunch the numbers yourself, please don't take my word for it. All I am suggesting is that some peoples opinion on the subject are a bit questionable regardless on who they are. My real world experience also happens to agree with the math. I personally wouldn't blame cooling system problems on the grill (even an angry grill).
 
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pagrey

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What temps are you seeing on your gage? What temp thermostat do you have installed? I would suspect you are the extreme but is great info for the rest of us to use as a base line.
Stock thermostat and the gauge points up. I don't trust the numbers on it too much. Overall I think most of us agree if the stock system is healthy you'll have no problems no matter what you do.

I worry if it gurgles when I shut it off, if the fan isn't loudly complaining when the gauge starts to climb or if there is too much or too little coolant in the reservoir. Beyond that I'm okay with whatever the gauge wants to do.
 
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Ericict

I don't proofread for your enjoyment.
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Stock thermostat and the gauge points up. I don't trust the numbers on it too much. Overall I think most of us agree if the stock system is healthy you'll have no problems no matter what you do.

I worry if it gurgles when I shut it off, if the fan isn't loudly complaining when the gauge starts to climb or if there is too much or too little coolant in the reservoir. Beyond that I'm okay with whatever the gauge wants to do.
I get it, lots of variables. I use the engine to tell me what's happening, but I watch the gages as well. Too much aviation in me.
 

Sundowner

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I want to be like Jerry when I grow up, so: grille inserts are some sort of issue.

Now, in all seriousness: what, exactly, is the insert in question? Is there only one model available? If so...what is it?
 

EJD

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I got aluminum inserts for my Jeeps grill when I lived in Florida strictly because of Love Bug season. It was easier to power wash them off the grill and inserts than out of the a/c condenser.

I'm sure it restricts airflow to some degree but never enough to make my temp gauge shoot up high at all or anything. So until that happens, I don't see any issue with them.
 
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