HOW TO: Block radiator with coroplast to keep warm for winter

TDIGAZ

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Lots of threads about blocking front grill with pipe insulation to stay warm in the winter, also a few more about using coroplast plastic sheets.
Everyone says how easy the pipe insulation method... agreed, but I'm not a big fan of how it looks.
So I decided on the coroplast method and thought I'd capture a few pics as I went along... hope this helps answer a few questions on how simple and easy this method is also.

Step 1: Find coroplast sheet. They are available at dollar stores, home depot, or you can recycle an election sign :D.

Step 2: Cut 3; 7.5 x 29 inch sheets. Paint gray/black (optional):D

Step 3: Remove front grill... this is much easier than you would expect. I used the following video as a tutorial.
www.youtube.com/watch?v=14G3sMJ71Wk

Step 4: Fold each sheet in half and slide sheets down in front of radiator. The driver's side opening is slightly larger, so use that spot to work from and slide the sheets over one at a time. There is a channel at the bottom of the condenser to slide the sheets down into. This hold the sheets securely so no need for tape or anything else.





Step 5: Re-attach front grill, admire your work and enjoy the warmth.



Before the install, the car was running at a consistent 84 degrees C on the highway this November, I will monitor how well this works throughout the colder winter months.
 
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grey matter

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I also did this to my MK4 but it was too much for of a hassle to get it out when we had a few warm days. The foam insulation works for me because it comes off in a second. I also found some nice round 1 inch insulation at Rona for my MKVI that's absolutely perfect. Sits flush and real snug. Hardly noticeable. 10 feet for $5.00. Only works for the top grill. Need the half inch pipe insulation for the lower. Call me cheap!
 

deflux

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If you do this theres really no need to remove it when the weather warms up temporarily. Put it on in the fall and take it off in the spring. These engines don't produce enough heat for it to matter...
 

nkgagne

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Pipe insulation in the upper and lower grills. In the thaw on Monday I did see as high as 98 C via my OBD app. Lots of slowing down and speeding up (asshat traffic). Not high enough to cause concern, but it's still higher than normal temp. Figured I'd add a data point.
 

amit9

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Before the install, the car was running at a consistent 84 degrees C on the highway this November, I will monitor how well this works throughout the colder winter months.
Mine used to run at that temp before I changed my t-stat. You may want to look into that as well. It will run at 88C-90C without the rad block.
 

TDIGAZ

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Nice write up Gary !
Thanks Matt, and to all, for everyones feedback.
So far it hasn't been cold enough to see how effective this is. No real change in coolant temps, so currently I see that as a good thing. I will wait for the cold days of January/February to see what coolant temps are then.
Agree that a t-stat change could help, but will wait for that.
 

TDIGAZ

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So far it hasn't been cold enough to see how effective this is...
Well yesterday morning was a great test to see how effective the coroplast covering is.
Left for work and the air temperature was -27 deg.C with windchill at -35 deg.C. After about 5 minutes on the 401 the coolant temperature reached 83 deg.C (according to Torque Pro) and stayed around that for my 1 hour commute.
That's good enough for me :).
 

imo000

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Well yesterday morning was a great test to see how effective the coroplast covering is.
Left for work and the air temperature was -27 deg.C with windchill at -35 deg.C. After about 5 minutes on the 401 the coolant temperature reached 83 deg.C (according to Torque Pro) and stayed around that for my 1 hour commute.
That's good enough for me :).
And what would have been without it?
 

LNXGUY

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And what would have been without it?
Probably the exact same, lol. I find that when people complain about their TDI not heating up, they've got the fan blasting and the temp dial all the way in the red. Go figure the car takes forever to heat up when you're sucking any heat out of the system.
 

McGuillicuddy

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I've honestly not noticed a large difference in passenger compartment warm-up time compared to petrol cars. I think the major difference is that the gasser will warm up within a few minutes in your driveway idling while the TDI will not. But under load (i.e. while driving), the warmup times are not noticeably different to me.
 

OMALLEY_808

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Electric heat does wonders for this! :D

Probably the exact same, lol. I find that when people complain about their TDI not heating up, they've got the fan blasting and the temp dial all the way in the red. Go figure the car takes forever to heat up when you're sucking any heat out of the system.
 

TDIGAZ

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Remember to remove once warmer weather starts coming!
Removed the coroplast rad cover today... literally took 5 minutes to do.
The coroplast sheets look just the same as when they were put in, so they'll be reused next winter.
Now to get the winter tires off...
 

dlb

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Nice work btw .... been using the pipe insulation. I may give this a try next yr ... well done !!
 

peterdaniel

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Can someone show me what this pipe insulation looks like exactly?
Thanks!
Pete ( in nice for the most part Sunny CA )
 

Andrew Dale

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Even though i live in southern BC this doesn't totally make winter driving the warmest experience. I personally prefer to plug in my car overnight and give it plenty of time to warm up
 

TDIGAZ

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Considering the time of year, and the fact there should be lots of recyclable coroplast throughout the country (aka election signs :)), I thought i'd bump this thread to the top.
I'm still on my original set from 5 years ago, and it really does take only a few minutes to put in and take out.
Just a few notes on my original post. The video I linked for the front grill removal shows them completely removing the grill. It is not necessary to unclip the hood release pull; simply pivot the loose grill upwards and there is lots of space to install the coroplast sheets (as in my 3rd picture).
I know a few people have questioned how effective the coroplast is versus the pipe insulation method, and since I've never tried the latter, I can't really say.
But for the ease of installation, and the fact that it doesn't change how the front end looks, and it's reusable for many years, it's what I've been doing.
 

Jetta_Pilot

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Just a thought on my part. If I were to do something like that, which I have no need for. I would opt for the pipe insulation, snap on/snap off and if you're concerned about how it looks, use aluminum paint and paint the insulation silver!


No need to undo anything on the hood release or turn the grill.
 

lanorg

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If anyone has difficulty getting the coroplast, I use a sheet of cork under padding, cut to the desired size. It sits nicely in the rad from below, is cheap, doesn't disintegrate, and hasn't burned. I've run a little over 100,000km with this particular mod on 3 different ALHs.
 
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