Purging coolant system methods.

CFTDIdriver

Veteran Member
Joined
Aug 17, 2014
Location
Central Florida
TDI
2003 Jetta TDI, 2011 Jetta TDI Sportwagen
I have a 2011 Jetta Sportwagen TDI and need to purge the coolant system and refill. I'm the second owner of the car and the coolant appears to be a little contaminated (looks brownish in color) for some reason... The previous owner or a service tech that didn't know better, might have topped it off with the wrong coolant type or something.

This model doesn't have a drain valve so per some instructions I read here (http://forums.tdiclub.com/showthread.php?t=361404), I attempted to disconnect a radiator hose in two locations, but soon realized this was much easier said than done... Disconnecting the clamps or clips was not too difficult, but getting the hoses to come apart in the tight area where they are located was not easily done without taking the risk of damaging something. I ended up backing out on my first attempt so far...

Anyone have luck with purging the system with a vacuum tool, compressed air, or similar to how repair shops do it (without disconnecting hoses and such)?

I know I can pay to have it done for around $130, but I already have the coolant (purchased (4) 1.5 liter bottles of Pentofrost ++ from a local NAPA store awhile back) and don't mind doing it myself if I can do it without too much trouble.
 
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Ol'Rattler

Top Post Dawg
Joined
Jul 3, 2007
Location
PNA
TDI
2006 BRM Jetta
Sounds like the PO put the wrong coolant in to top off and now you may have brown sludge/cottage cheese forming in your cooling system.

There is no petcock to drain the system. You have to remove the lower radiator hose and at least one of oil cooler hoses to drain.

Each time you drain, you only get slightly more than half of the system capacity out. What I do is drain, refill with distilled water and run the engine to mix. And then I repeat about 5 more times until what drains out is clear.

After that, I refill the system with 1/2 the system capacity with undiluted coolant and fill the remain system volume with distilled water. A no brainer 50/50 mix when you are done.

No real shortcuts on this one. Once someone puts the wrong stuff in, you have to get the system back to clear water and then restore to 50/50 with the correct stuff.
 
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CFTDIdriver

Veteran Member
Joined
Aug 17, 2014
Location
Central Florida
TDI
2003 Jetta TDI, 2011 Jetta TDI Sportwagen
Yes, I may resort to digging further in to it and removing a hose or two to drain the system as much as possible, but was hoping I could get the job done using another method even if it meant purchasing a tool to do so. I don't mind spending a reasonable amount of money on a tool instead of spending around the same amount of money having it done (supplies + labor), if it is something that could be used multiple times or on other vehicles I own as well.

My 2003 Jetta TDI has the petcock valve to drain the system and I've flushed the system similar to how you mentioned it, but having to remove a hose to do so is kind of a pain since there is less room to work with on this model.
 

jason_

Veteran Member
Joined
Jun 2, 2014
Location
michigan
TDI
2015 s wagon dsg
If you pull the plug from the block, shouldn't that drain the block? And killing a hose should do radiator, what little is left are dribbles and Heater core?

Sent from my rooted HTC Supersonic using Tapatalk 2 Pro
 
Joined
Oct 10, 2017
Location
Media, PA
TDI
2011 Golf Tdi
I have a 2011 VW Golf TDI and when I removed both lower radiator hoses on either side of bottom of radiator no coolant drained out. The engine was cold and car had been sitting for several hours. I know I have coolant in the system but removing hoses did not remove any coolant. I would like to change my coolant and have been searching the internet and this forum but I found no one having this problem. Any suggestions would be helpful. Thanks in advance.
 

turbobrick240

Top Post Dawg
Joined
Nov 18, 2014
Location
maine
TDI
2011 vw golf tdi(gone to greener pastures), 2001 ford f250 powerstroke
I have a 2011 VW Golf TDI and when I removed both lower radiator hoses on either side of bottom of radiator no coolant drained out. The engine was cold and car had been sitting for several hours. I know I have coolant in the system but removing hoses did not remove any coolant. I would like to change my coolant and have been searching the internet and this forum but I found no one having this problem. Any suggestions would be helpful. Thanks in advance.
Sounds like you may have removed the intercooler hoses, not the radiator hose. After removing the lower radiator hose you can apply some compressed air via the expansion bottle overflow hose to help push out the coolant. I basically use Ol Rattlers flush method (haven't actually needed to flush my tdi).
 

Henrick

Top Post Dawg
Joined
Aug 24, 2010
Location
Ireland
TDI
Golf VI TDI, 77 kW (CAYC)
Undo the expansion bottle cap to remove any pressure in the system.
Remove lower radiator hose and drain the coolant.
Reassemble.
Fill with distilled water (do not use tap water).
Take the car for a spin, or better yet leave it like that for a few days (assuming ambient temps are over freezing point). Drive the car as normally.
After a few days, remove lower radiator hose and drain the contents, reassemble.
Refill with distilled water, repeat the same procedure.
After a few days, remove lower radiator hose and drain the contents, reassemble.
Refill with concentrate mixed to about -45 *C freezing point.

In the end you should end up with coolant at around -37-39 *C freezing point and clean coolant system.
 

meerschm

Top Post Dawg
Joined
Apr 18, 2009
Location
Fairfax county VA
TDI
2009 Jetta wagon DSG 08/08 205k buyback 1/8/18; replaced with 2017 Golf Wagon 4mo 1.8l CXBB
another way is to actually flush the system.


I used a plastic adapter from a prestone flush and fill kit.


https://www.myturbodiesel.com/data/photos/l/1/1317-1431118400-3bd9723a440b42a01acf5805db960ced.jpg



I put a photo over at the myturbodiesel site. (might have to register to see) I would post it here, but my account seems full, and I really do not want to pay up for an updated account again this year. if you send me a message, I could send a couple photos.




pulled one of the lines from the transmission cooler, slipped the flush T into the hose, and used a short length of clear plastic tube to connect the other end of the T to the cooler fitting. this let me hook a garden hose and flush away.



Not too difficult to catch flushed antifreeze for proper disposal/recycling. I pulled the drain hose from the expansion bottle, and routed a hose it fit into over the side.


also had the lower radiator hose disconnected, off and on, while I flushed quite a bit out.


it also helps to use a little air to push fluid out, but don't want to go nuts.






there are two circuits for coolant, so to be complete, you might want to do the same trick with a heater hose, but this is a little harder to get to.




after you push all the nasty stuff out, you can fill/drain a couple cycles with distilled water and then the proper coolant to get the right mix.
 
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