Drilling a drain hole in the intercooler plumbing

afarfalla

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I took my intercooler tube off and got nothing out of mine. Some oil residue but nothing out of the norm. 34k miles never been checked before, outside all the time in Chicago weather.
I expected nothing, was surprised when that amount of water flowed out? It very rarely freezes here.
 

ihatespeed

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I had a tough start last winter, crank catch stall etc.. I in a panic removed the inter cooler hose and found nothing but maybe a tsp of oil. no sign of water at all on a car with over 80,000 mile
 

VeeDubTDI

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Let's give his thread a try and see what we come up with in regard to drilling drain holes in the intercooler plumbing.

It would be very helpful to keep this thread on the topic of a drain hole and long-term experiences, so let's keep general intercooler icing discussion in the other (long) thread.
 

afarfalla

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drove the car with the hole in the intercooler, local only, parked it checked 2 hours later no drips no water. Will do some frwy driving tomorrow to see if any cell's pop up
 

02PSDV8

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Wondering if its a good idea to install a petcock valve like you'd lind on a radiator? Then you could open it up once in a while to drain?
 

SilverGhost

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The other consideration is the computer being sensative enough to log a boost leak. I have had very small cracks and loose clamps set DTCs. Its possible that a hole big enough to do the job will set a DTC. Then you have to worry about DPF clogging because the ECM won't regen with a boost DTC.

Argh!! crappy charge air cooler design.

Jason
 

2011tdiproject

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Thank you, moderator who gave me my thread back! I hope I didn't come across like I have a huge ego, because I really don't. Having said that, it is not because of ego that I wish the thread had my original title, or "drilling a drain hole for the intercooler", not "in the intercooler", because I am not drilling a hole in the intercooler, I am drilling a hole in the charge air piping next to the warm oil pan.

Anyway, I really want to emphasize one thing here that has been brought up repeatedly. I do NOT want a valve on that pipe. The reason why the people who've said things along the lines of "it's okay as long as you plug it back up", is psychological, not based on engineering. They think because the hole "isn't supposed to be there" that a valve is better, without looking at how the idea of the hole actually works. With a valve, you're not going to know when to open it. You won't know when water is accumulating, or when ice that is going to melt later is forming. You might never open it at the right time, you might open it when the water is still ice, and think there's nothing there. You might forget to open it. You might have to open all the time, way too often.

With the hole, it drains any time water is there. Whether you're driving, whether the car it parked, whether you're there or not. Therefore the hole is a much better idea. Human effort and error factor is out of the equation.


So far I haven't taken the car out other than around town and a few aggressive accelerations to see if I'd get an error code, which I did not. I may have a 3 hour drive later today, but I might put that off. It is snowing, 0 degrees out, and I am pretty tired after cutting, grinding, welding, breathing paint fumes, etc until about 6 AM last night doing fab work on my 95 chevy cummins swap. 2wd 350/4l60 to d60/14ff, divorced np205, 12v p7100, nv4500, 37s, no lift blocks, no body lift. Insane amount of work.
 
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2011tdiproject

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https://www.flickr.com/photos/37674324@N07/sets/72157649706285690/ first pic is what I collected when I removed the intercooler hose, I drilled a 3mm hole in plastic section, replaced hose started car. It would pee then stop then pee some more when the RPM's were increased water would stop for a second or 2 then continue peeing, I quilt after about 3 minutes. I removed the left side hose but nothing came out. I assume my original no-start then dead battery was water ingestion?

The hole you drilled is quite a bit bigger than what I drilled. I don't remember the exact measurement of the bit I used, but I think it was like .05" or so, less than half the size of the 3mm bit you used. Hmm..
 

2011tdiproject

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The other consideration is the computer being sensative enough to log a boost leak. I have had very small cracks and loose clamps set DTCs. Its possible that a hole big enough to do the job will set a DTC. Then you have to worry about DPF clogging because the ECM won't regen with a boost DTC.

Argh!! crappy charge air cooler design.

Jason
How would the computer know about the tiny boost leak? MAF signal vs 02 sensor feedback? As far as I know, the car does not have a MAP sensor, no way to read a discrepancy between MAF and MAP readings, which would easily indicate a boost leak.

I wouldn't say it's the design of the charge air cooler, I believe it's primarily a function of the low pressure EGR dumping all that humidity into the intake tract. However, the humidity does keep it cleaner with the crankcase ventilation residue, it makes that residue not as "sticky", and easier to drain out, for lack of a better way of saying it.
 
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Slurry Pumper

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Why not install one of these?
After your oil change you can open this up, take it for a spirited drive then close it back up and be done.



Sent from my SM-G900W8 using Tapatalk
I like this idea better than just a hole. If there isn't really access to the intercooler, and I know that there isn't, I will just place a hose out the intercooler to the stop cock. I have never had this problem, so I will not be in a rush to go out in the cold and crawl under the ole TDI with a drill bit, rubber grommet, hose, stop cock, and a beer unless the car starts choking on starts every morning.
 

2011tdiproject

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I like this idea better than just a hole.
Why? Like I said, it's psychology, not engineering. The hole "isn't supposed to be there", so you don't want it there. That's all it is. All you guys talking about valves, you're making this way harder than it has to be.

Yes, I will eat those words if I get an error code, but we'll see.
 

mishkaya

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2011tdiproject
Do you monitor EGT's? I would would be curious to know what the temps were prior to the hole and after. I know that on my ram when one of the 1/8" hoses popped of the upper intercooler hose, I had enough of a boost leak to see a 100 degree rise in EGT's under moderate boost conditions. Even more of an increase under high boost engine loads.
mishkaya
 
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JASONP

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I like this idea better than just a hole. If there isn't really access to the intercooler, and I know that there isn't, I will just place a hose out the intercooler to the stop cock. I have never had this problem, so I will not be in a rush to go out in the cold and crawl under the ole TDI with a drill bit, rubber grommet, hose, stop cock, and a beer unless the car starts choking on starts every morning.
If location is an issue you can install it in another location and run a feeder tube to it for easier access.

Sent from my SM-G900W8 using Tapatalk
 

2011tdiproject

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2011tdiproject
Do you monitor EGT's? I would would be curious to know what the temps were prior to the hole and after. I know that on my ram when one of the 1/8" hoses popped of the upper intercooler hose, I had enough of a boost leak to see a 100 degree rise in EGT's under moderate boost conditions. Even more of an increase under high boost engine loads.
mishkaya
No, I don't have an egt gauge or vcds thing, and I haven't put any miles on the car out of town yet either.

Your higher EGT makes sense, you had the same fuel and less air. As I wrote, the hole I drilled was something like .05".

For comparison: A .05" hole has .0019 square inches.

A 1/8" hole is .0122 square inches, a 625% increase.

Even .05" probably is bigger than necessary, the drill I had wouldn't hold any smaller of a bit!
 

TRAMPLINEMAN

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Why not install one of these?
After your oil change you can open this up, take it for a spirited drive then close it back up and be done.



Sent from my SM-G900W8 using Tapatalk
This would work great if the thickness of the wall of the pipe was the same as the depth of the threads on the valve. But, I don't believe that to be the case. A valve like this would stick too far into the pipe and all the water wouldn't be able to drain out. If you welded a bung to the outside of the pipe, then screw the valve into the bung, it could be flush with the inside of the pipe allowing all the water to drain out.
 

ATR

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This would work great if the thickness of the wall of the pipe was the same as the depth of the threads on the valve. But, I don't believe that to be the case. A valve like this would stick too far into the pipe and all the water wouldn't be able to drain out. If you welded a bung to the outside of the pipe, then screw the valve into the bung, it could be flush with the inside of the pipe allowing all the water to drain out.
Indeed! I could see some obstacle yanking a fitting like that off the pipe and taking some of the pipe that was it was attached to with it. Not to mention that it sticks up into the pipe which is a bad thing because it will prevent water below the rim from draining out. depending on how far it sticks into the pipe that could be a substantial amount of water.

2Micron has the best valved solution because nothing hangs down below what would normally hang down. It also sits right at the bottom of the pipe allowing ALL the water to flow out:
Reserved for the “Drain Flow” Intercooler Kit.

Coming Soon!!!

.

.

.
Go Ahead, Click Them!!!!!

.
All the best!!
 

afarfalla

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took my hole down the frwy

no codes, ran fine, .3cm works just OK
 
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Rolyak

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No automotive engineer would approve drilling a hole in the intake system.

Based on 30 years of Cummins experience and my turbo Volvo it essentially can be a vacuum leak. Under a load, fuel creates boost, let off the throttle it's back to vacuum.

My Volvo can blow 10 psi under full load but will cruise at 12"/HG (vacuum).

Truckers liked to cut holes in the intake pipes to spray a shot of ether, doing an overhaul they got a new intake pipe or voided their warranty.

Oh yeah, the Volvo has a factory intercooler drain plug.
 

Aztraveler

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What has always concerned me about the valve idea, is possible freezing in the valve and the valve becoming damaged.

I like the drilled hole Idea because no moving parts. Nothing to freeze and become damaged.

I am interested to hear about the long term results. Both valved and drilled.
 

Dirtracr95

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no codes, ran fine, 3cm works just OK
3mm

a 1.1811" hole would be huge.

I think the hole that 2011tdiproject made is going to be too small. A single drop of water could cling to the hole and freeze not allowing water to drain. There probably is an optimum size if one were to drill a hole its just a matter of determining it.
 
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Chris

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Bloomfield Hills, Michigan, USA
I think people are over thinking this.

A simple, small hole will result in an undetectable boost loss and will drain water when pressurized.
Many mufflers are manufactured with little drain holes with no noticeable noise problems.
 

afarfalla

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3mm

a 1.1811" hole would be huge.

I think the hole that 2011tdiproject made is going to be too small. A single drop of water could cling to the hole and freeze not allowing water to drain. There probably is an optimum size if one were to drill a hole its just a matter of determining it.

lets get back on track. Here is what lead to me drilling a .3CM not .3MM (my mistake) hole in my intercooler line...diesel $2.59 gal car automatically turned into the gas station for fill-up, when I was finished the car would start-catch and stall, did this 3 times out of the blue for no reason? now battery is dead got a jump, started like normal, drove 50 miles home. Posted to the forum and the idea was water ingestion, cylinder hydro lock, made sense to me, now remember I live in South Texas its against the law for water to freeze. The next day I pulled the right side hose and water came out, about a half a champagne glass. Drilled a 3CM hole, in the plastic neck, started the car and water pee'd out of my engineering master piece, I had a working hole. Took car out for a ride, local, everything seems fine, today we did some frwy driving again no problems. I checked my hole later in the day and all is dry, no floor drips, no evidence of water.
 
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afarfalla

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No automotive engineer would approve drilling a hole in the intake system.


I believe the forum members are one up on VW engineers, don't be surprised if on the 2016 models a little hole shows up right where I drilled mine. All the gadgets that are being thought up as a remedy will work just fine here in South TX and South FL but in the white belt intercooler water will just freeze? Lets just keep an eye on my hole, if anything pops up I'll write it up and you can all peek
 
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VeeDubTDI

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lets get back on track. Here is what lead to me drilling a 3CM not 3MM hole in my intercooler line...diesel $1.79 gal car automatically turned into the gas station for fill-up, when I was finished the car would start-catch and stall, did this 3 times out of the blue for no reason? now battery is dead got a jump, started like normal, drove 50 miles home. Posted to the forum and the idea was water ingestion, cylinder hydro lock, made sense to me, now remember I live in South Texas its against the law for water to freeze. The next day I pulled the right side hose and water came out, about a half a champagne glass. Drilled a 3CM hole, in the plastic neck, started the car and water pee'd out of my engineering master piece, I had a working hole. Took car out for a ride, local, everything seems fine, today we did some frwy driving again no problems. I checked my hole later in the day and all is dry, no floor drips, no evidence of water.
The picture on your Flickr is definitely not a three centimeter hole. Three centimeters is more than an inch!

https://flic.kr/p/qFf4cT
 

JasonG

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This looks like a perfect fix.

[Edited]
Just to clarify as people are getting hung up on a minor point.
1/8"=0.125"
3mm=0.119"
7/64"=0.1093"
3/32"=0.0938"=2.38mm
1/16"=0.05"=1.27mmm

I believe Afarfalla stated he used a 3/32" drill bit. A 2.5mm would be the nearest equivalent.
The OP 2011TDIproject used a 1/16"=0.05"=1.25mm
 
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