# Why is there not a comprehensive coolant flush DIY?



## formerly silveratljetta (Feb 6, 2007)

I want to flush my coolant soon because i have 92k miles and I want to flush it because I am not sure if the PO did it or not. I have read some of the archives, but I would like a comprehensive guide so I can make sure I don't screw anything up. I know I need a 50/50 mix of g12 and distilled water. The radiator drain valve is on the driver's side. I should flush the system when the car is completely cold. I should also open the radiator overflow cap so that air can escape too I think??? Cmon guys help me out. I have done as much research as I can at this point.


----------



## LemolfGTI (May 14, 2007)

bump this up! 
I was also searching for exactly this last night !


----------



## crassett (Mar 9, 2005)

*Re: Why is there not a comprehensive coolant flush DIY? (formerly silveratljetta)*

I too would like to know, free bump!!!!!!!!!


----------



## atlaudispeed (Aug 24, 2005)

*Re: Why is there not a comprehensive coolant flush DIY? (formerly silveratljetta)*

I'm pretty sure I read you just run water through the system with the engine idling and allow that to flush through for a few minutes. Then drain and refill with coolant/water mixture.


----------



## WhiteG60 (Aug 20, 2001)

*Re: Why is there not a comprehensive coolant flush DIY? (atlaudispeed)*

Heres your DIY:
Open the drain on the bottom of lower radiator hose where it connects to the radiator.
Let it drain out
Start the car and put a hose in your coolant ball and let it cycle through until the liquid coming out of the drain is 100% clear water
Turn hose off
When water stops flowing out freely, shut valve
Fill coolant ball with coolant/water mixture until full
/thread


----------



## formerly silveratljetta (Feb 6, 2007)

I don't want to run hose water through my engine. I might just go pick up like 10 gallons of distilled water from kroger. Are you supposed to open any top cap of the radiator to let air release or not?


----------



## TurboZen (Oct 15, 2000)

*Re: (formerly silveratljetta)*

I'd trust WhiteG60's suggestion. you aren't going to get deposits running with tap water for that short of a period of time.


----------



## WhiteG60 (Aug 20, 2001)

*Re: (TurboZen)*

Correct. The water isn't going to even have time to get hot. Its gonna flow out warm.


----------



## formerly silveratljetta (Feb 6, 2007)

*Re: (WhiteG60)*


_Quote, originally posted by *WhiteG60* »_Correct. The water isn't going to even have time to get hot. Its gonna flow out warm.

ok thanks man. I will try and get this done next week. Anyone know how much a jug of G12 is at the dealer these days?


----------



## WhiteG60 (Aug 20, 2001)

*Re: (formerly silveratljetta)*

I see them online for ~ $17 total. If you're going to do it next week, just get it from GermanAutoParts.com got $17 + shipping. Dealer is ~ $26 if i'm not mistaken.


----------



## formerly silveratljetta (Feb 6, 2007)

thanks for all the help. Ive been meaning to do this for awhile.


----------



## gonorthanddub (Mar 12, 2007)

*Re: (formerly silveratljetta)*

i know it's an old thread, but I found this DIY on blauparts.com and it seemed very thorough.......
How To Change Engine Coolant On A Vw 4 Cylinder (1998 - On) :
1. When the engine has cooled down, remove the Vw coolant tank cap. 
2. Draining the Vw coolant from the 4cyl cooling system:
Remove the lower radiator drain plug from the lower front of the radiator (Vw A4, Vw Passat). Remove the passenger side lower radiator hose. Remove the outer Vw coolant hose that connects to the oil cooler. To drain the heater core you'll need to remove the hose on the coolant flange or transfer pipe located on the back side of the engine. This hose goes from the cylinder head to the heater core. 
3. After the system is done draining, put the Vw coolant tank cap back on. Carefully work off and remove the smallest hose that is connected to the top of the Vw coolant tank. Be careful, the tank nipple likes to crack and break off. 
4. With a blow gun and compressed air on low, carefully insert the blow nozzle into the small hose. Wearing safety goggles, carefully force the air out so that any Vw coolant that's still trapped in the cooling system is released. 
5. Reinstall the Vw coolant drain plug. Reinstall the coolant tank hose(s). Fill the Vw cooling system with distilled water. Start the car and air bleed the cooling system as outlined in the factory Bentley manual. Run the car until the cooling fan comes on. 
6. Repeat steps 1 through 5 until the water comes out clean. 
7. Verify that you have the correct anti-phospate anti-amine G11 or G12 Vw coolant. If it's full concentrate, mix a 50/50 ratio per the Bentley manual. Fill your Vw cooling system with this 50/50 mixture. Note: Some factory Vw coolants sold by dealers are already premixed and do not require further delusion. 
8.Run the 4cyl engine and check for any Vw coolant leaks. 
9. Top off the coolant tank to the fill line. Do not overfill. 
10. Using a permanent marker, write 'G11 or G12 Coolant Only' on the Vw coolant tank. 
11. (optional) Be environmentally responsible and dispose of your old Vw coolant properly. 
Vw Coolant System Maintenance: 
1. Never top off the coolant tank with full concentrate G11 or G12 Vw coolant. Your Vw coolant should never exceed a coolant ratio of 80%. If it's over 80% an inefficient Vw cooling system will result, decreasing flow through the radiator along with poor heat transfer through the engine block. 
2.Always top off your Vw coolant tank using a 50/50 mixture. If you're in a pinch and don't have any, use a small amount of distilled water. Remember, adding large amounts of water will change the alkalinity of the Vw coolant and throw off the glycol to water ratio, making it less effective in cold temperatures. 
3. Never mix G11 blue coolant and G12 red coolant. It will turn into a brownish goo and plug up your Vw cooling system. 
4. We highly recommend flushing your Vw's coolant when replacing your timing belt. 
found it here..http://www.blauparts.com/vw/vw_fluid/vw_coolant_engine_fluid.shtml#vw4clycoolantchange
http://****************.com/smile/emthup.gif


----------



## scrappy62 (May 21, 2005)

*Re: (gonorthanddub)*

I plan on doing this today. How much G12 do I need to do this job? I didn't realize this was so in-depth. I pulled a P2181 code "Coolant Performance System", and just bought a new coolant temp sensor. Next step is to drain + add new coolant. Any other advice would help.
Mike


----------



## TmoeJ747 (Oct 10, 2007)

*Re: (scrappy62)*

i would also suggest replacing the thermostat as well. you have to drain the coolant to change it anyways, and your code could also be caused by a stuck open t-stat (i believe).


----------



## herb2k (Jul 29, 2007)

*Re: (scrappy62)*

I did mine a few months ago, because the shop that replaced the thermostat mixed some green coolant into the system.
You only need 1 jug of G12 for the 1.8T. Mix it 50/50 with distilled water and you have enough for the whole system (and some left over for topping up).
I didn't have to disconnect any rad hoses, since I had my thermostat replaced already.
Simply open the drain at the driver's side of the rad, open the lid for the coolant bottle, and wait for it all to drain out. There is no radiator cap in the MK4 cooling system as it is completely sealed.
You can do a flush with some of that cooling system flush stuff, or just flush it with hose water and engine idling (helps to have anther person to work with). 
Here's what I did:
Drain and fill with hose water as described above. Close off the drain cap once clear water runs out of the system.
The cooling system flush stuff I used said to run the engine for about 10-20 mins to allow it to work its way through, also make sure you run the car's heater at full blast so that coolant is allowed to run through the heater core. 
Drain out all of that stuff (it's pretty soapy) and flush with hose water until it runs out clear from the drain port (with engine idling). 
Start filling it with your G12 mixture, but leave the drain port open until you see only bright pink G12 flowing out, then close it up and top off the system. 
Make sure to dispose of the old G12 coolant properly, and you're done. Took us about 3 hours taking our time and making sure all the gunk was flushed out. 

_Modified by herb2k at 6:15 PM 12-6-2008_


_Modified by herb2k at 6:17 PM 12-6-2008_


----------



## scrappy62 (May 21, 2005)

*Re: (herb2k)*

thanks for the input. How big is the 1 jug of G12 I need for the 1.8T? A gallon? I see different sizes listed on ecstuning.com
thanks, Mike


----------



## herb2k (Jul 29, 2007)

*Re: (scrappy62)*

Yep, my bottle from the dealer was 1 gallon.


----------



## scrappy62 (May 21, 2005)

*Re: (herb2k)*

Doing this on Saturday. Do I need to remove my front valence to get at this drain?


----------



## Boostin20v (Mar 22, 2000)

*FV-QR*

No, the lower rad hose is farther under the car and has no direct interaction with the bumper/valance.


----------



## scrappy62 (May 21, 2005)

*Re: FV-QR (Boostin20v)*

hmmm... Is there a pic someone can point to the radiator hose I'm supposed to remove? How about reattaching it? Is there a cable or fastener I'm supposed to reattach?
I bought the gallon of G12 and 1 gallon of distilled water. Plan on doing this in the morning.
Thanks, Mike


----------



## UntouchableGTI (Apr 30, 2006)

*Re: FV-QR (scrappy62)*


_Quote, originally posted by *scrappy62* »_hmmm... Is there a pic someone can point to the radiator hose I'm supposed to remove? How about reattaching it? Is there a cable or fastener I'm supposed to reattach?
I bought the gallon of G12 and 1 gallon of distilled water. Plan on doing this in the morning.
Thanks, Mike

the bottom hose............theres one 2 hoses total, top and bottom


----------



## dr. sandwiches (Apr 9, 2009)

*Re: FV-QR (UntouchableGTI)*

Hey guys,
I am looking for some diy info on draining my jetta 2.5 mkv coolant. I read on this thread that you just let the old coolant drain out of the lower radiator drain. What about the coolant that is in the engine block? does this old coolant also drain out from the radiator drain?
I am asking this because on my previous car (honda accord), you had to remove a drain bolt on the engine block in addition to the drain plug on the radiator in order to completely drain the system. Otherwise you only drain half the old coolant in the system. which leads to old coolant left in the system. Also an improper mixture ratio of new g12 to water in the system, especially if you are flushing the old coolant out with garden hose water. either way you are screwed.
Basically what i need to know is if you remove the drain hose/plug from the radiator does the entire coolant drain out.


----------



## xXSLVR6Xx (Jun 4, 2007)

After reading through these posts it seems that when you drain the system and run hose water through, the engine will drain also while car it at idle meaning you get the bulk of coolant drained first then run the hose water and start motor and allow system to cycle through untill water flows clear. Close cooling system and fill with G12(apprx 1Gal) then top off with water or coolant.
This Good?


----------



## hootyburra (Feb 19, 2007)

*Re: Why is there not a comprehensive coolant flush DIY? (formerly silveratljetta)*

saving this for spring car work weekend


----------



## I Drive a Jetta (Jan 9, 2010)

*Re: Why is there not a comprehensive coolant flush DIY? (hootyburra)*

Would these instructions work on a 1999.5 2.0 automatic?


----------



## Oh_My_VR6 (Sep 6, 2004)

*Re: Why is there not a comprehensive coolant flush DIY? (I Drive a Jetta)*


_Quote, originally posted by *I Drive a Jetta* »_Would these instructions work on a 1999.5 2.0 automatic?


Yes.


----------



## zeusenergy (Feb 25, 2008)

*Re: Why is there not a comprehensive coolant flush DIY? (formerly silveratljetta)*

I'm going to add this even though I might be flamed.... you CAN run plain green coolant (get quality stuff though) AFTER DRAINING and FLUSHING all of the old G12 out. This way the price for coolant is less even using quality coolant, and you can get it anywhere. Again, be sure your mix is 50/50 with distilled water and all of the old G12 is flushed out clean. Keep the drain open on the lower radiator hose till all the hose-supplied plain water runs out. Remove hoses at their lowest points where possible and let the plain water flow from there as well, and keep the heater on the whole time. 
Or, flush once, refill with distilled water only, run it for 5 minutes with the heater on, drain and refill with the permanent coolant and distilled mix. This will guarantee most of the old coolant and plain tap water is gone. The system doesn't quite take two gallons or so.


----------



## Raz2099 (May 10, 2009)

just finished my coolant flush about an hour and a half ago, my coolant light keeps flashing and the heat goes from warm to cool over and over. i think im gonna half to do this again, since i forgot to turn on the heater on full blast


----------



## zeusenergy (Feb 25, 2008)

*Re: (Raz2099)*

Thats key to keep the heater on and pumping while the draining and refilling is going on.


----------



## Raz2099 (May 10, 2009)

turns out i had too little coolant in the system, but its taken care of and everythings nice and cool now


----------



## TurboLover03 (May 28, 2003)

zeusenergy said:


> I'm going to add this even though I might be flamed.... you CAN run plain green coolant (get quality stuff though) AFTER DRAINING and FLUSHING all of the old G12 out. This way the price for coolant is less even using quality coolant, and you can get it anywhere.


 What are a couple examples of "GOOD" coolant to use in place of the G12? I'm thinking about doing the flush too and going to something a wee bit cheaper. $30 for a gallon of G12 from the dealer is just outlandish.


----------



## herb2k (Jul 29, 2007)

TurboLover03 said:


> What are a couple examples of "GOOD" coolant to use in place of the G12? I'm thinking about doing the flush too and going to something a wee bit cheaper. $30 for a gallon of G12 from the dealer is just outlandish.


 
You can use whatever you want, as long as you completely flush out the old G12 mixture.


----------



## filthyillness (Feb 13, 2010)

ECStuning.com has 1 gallon of G12 (Pink) for $20+. About to order this and do my t-state and flush as soon as it gets here. 

Anybody can link a DIY for the t-state change?


----------



## sounrealx (Apr 4, 2007)

http://forums.audiworld.com/showthread.php?p=16925102


----------



## Cadenza_7o (Jan 23, 2001)

*Coolant/antifreeze alternatives*



TurboLover03 said:


> What are a couple examples of "GOOD" coolant to use in place of the G12? I'm thinking about doing the flush too and going to something a wee bit cheaper. $30 for a gallon of G12 from the dealer is just outlandish.


If the cooling system is flushed clean of VW's G12 coolant, you could use one of the following...

-Zerex DexCool ExtremeLife or Zerex DexCool









-Zerex G-05









Zerex DexCool/ExtremeLife is licensed by BASF, who holds the patent on the G12 coolant.. Supposedly G12 and DexCool are compatible (can be mixed) as they're both OAT formula, just different dyes. But a flush is always good to clean the system. 

Zerex G-05 is a Hybrid OAT and contains a small amount of silicates to minimize cavitation. Also a very good alternative.

Zerex coolant chart


----------



## cyclejerk (Sep 15, 2009)

*Just did this*

I did this in about an hour with no problems (in 25 degrees :snowcool. Before you do this go out and get a piece of clear plastic hose from the hardware store, (1/2"). With a little wiggling you can get the hose over the drain spout and it will make things much more clean and simple. I didn't have to jack up the car or remove any plastic shielding from underneath. 

Also for the noobs out there (like myself) no tools are needed to open and close the drain valve. Just twist and pull. 

After the flush was done I let the car run for 10 min with the cap off then drove around for 20 minutes. I needed to top off the fluid after that.


----------



## x_GTI_x (Apr 23, 2008)

So i just did the coolant flush today, followed all the steps and everything went pretty smoothly.

My question is, is it normal to have almost a gallon of the 50/50 mix left? i mixed it in a bucket and filled the coolant bottle, turned the car on, topped it off and everything is fine.

I waited for the water to stop dripping from the valve completely and everything, but im wondering if there was some water left over from the flush with the hose or its normal to have that amount of coolant left over?


----------



## Lythandra (Nov 19, 2006)

Just did this today and have a few questions.

I jacked up the front of my car and put it on stands so I could fit a bucket under the drain. Opening the drain, it was fairly slow to drain. Even running the car at idle and refilling the coolant ball it was slow to drain. Is that normal? Would having the cars front jacked up a bit affect draining speed?

Mine did not drain fast at all. The top hose of the coolant ball did have flow (again not alot but it did have some). My thermostat did open up and the bottom Rad hose got warm.

I'm trying to diagnose an overheating problem so just trying to find what is causing the problem. I had green coolant so am gonna replace that with the correct type.

I do have a green top temp thingy (it is fairly old tho, over 5 years) but my fans did not turn on while idling even tho I did get a bit over 190. Time to test the fans i guess.


----------



## raltgo (Jun 26, 2003)

formerly silveratljetta said:


> _Quote, originally posted by *WhiteG60* »_Correct. The water isn't going to even have time to get hot. Its gonna flow out warm.
> 
> ok thanks man. I will try and get this done next week. Anyone know how much a jug of G12 is at the dealer these days?


 Wow.......dont you guys know that VW its build touft.....dont get me roung i love, fix and have VW for life....i think its too much.....why? Because i know!


----------



## benyates (Jun 10, 2009)

just bought g12 from the dealer on a saturday for 23.57, can't remember if we were discussing that in this thread but i know people were asking


----------



## bigslim1976 (Jun 18, 2009)

zeusenergy said:


> I'm going to add this even though I might be flamed.... you CAN run plain green coolant (get quality stuff though) AFTER DRAINING and FLUSHING all of the old G12 out. This way the price for coolant is less even using quality coolant, and you can get it anywhere. Again, be sure your mix is 50/50 with distilled water and all of the old G12 is flushed out clean. Keep the drain open on the lower radiator hose till all the hose-supplied plain water runs out. Remove hoses at their lowest points where possible and let the plain water flow from there as well, and keep the heater on the whole time.
> Or, flush once, refill with distilled water only, run it for 5 minutes with the heater on, drain and refill with the permanent coolant and distilled mix. This will guarantee most of the old coolant and plain tap water is gone. The system doesn't quite take two gallons or so.


Wow, are you guys that anal that you won't spend $15 extra bucks for the recommended product for your cars? It's $25-$30 bucks people! Stop being cheap and do what the manufacturer specifies. If you do it right and your car runs properly you shouldn't have to continue to top it off. I went 10 years on my GTI before I did a coolant flush, and that's only because my temp sensor flange cracked and I had been adding generic coolant for a week until I had time to replace it. You guys are lames if you can't spend $30 bucks on something you guys say you care so much about! LAMES!


----------



## gdoggmoney (Feb 21, 2004)

Dear smart people who try to cheap out on coolant. You have dried G12 all along the inside of your hoses. Once it lets go -- and it WILL let go over time, your green coolant will mix with G12. It will turn into poo basically, and cause you to have cooling problems/lose an engine.


Thank me later
--gdoggmoney


----------



## hithard02 (Oct 4, 2008)

Granted the last post on this thread was nine months ago and now is the time that Bigslim1976 decided to bump it with a reply, it seems to be perfect timing.

gdoggmoney, I happen to be in the process of flushing out coolant from my wifes car and when we bought it, it was filled with dexcool (bottle in the trunk) and god knows what else. The coolant tank had a bunch of black gritty residue and the coolant was orange in color (same as mine using g-12).

I'm sure it is a no no on here but I was thinking of a vinegar flush to remove any old " dried G12 all along the inside of your hoses" as you put it. I have only seen one post on here of someone using vinegar in the flush but is seems to be a widely used acid to clean out coolant systems. 

Any input on this? Also the newest g12+ sold is supposed to be compatible with any other coolant.

"You guys are lames if you can't spend $30 bucks on something you guys say you care so much about! LAMES!"

Bigslim1976, I don't give two f*cks about this car, and $15 dexcotol is going back in it once it is fully flushed. Don't worry, I have a fresh bottle of g12 for my 1.8t.


----------



## alexander teas (Nov 17, 2012)

*Coolant Flush on 2000 Golf --- Boston Area*

I have a 2000 VW Golf that had a coolant leak over the summer, that was fixed. I was, however, adding water and regular coolant to it during that time. Now, it's starting to get cold and I think a coolant flush is necessary. I don't really have the tools, facilities and expertise to try this myself. 
My question--- where is a good place in the Boston area to have this done? 
Should I order G12++ coolant off the internet to save money? How many gallons? 

Thanks for your help.


----------



## joe'sGTI (Jun 12, 2007)

I used pentosin violet antifreeze, stuff works like a charm.


----------



## shookones2 (Jan 21, 2013)

can anyone post up a picture of where the drain spout is located? i like the idea of attaching a 1/2' clear hose to it and draining it out that way. i just dont know where the drain spout is located at, a picture of it would help me out the best


----------



## 01TornadoWolf (Jun 18, 2009)

shookones2 said:


> can anyone post up a picture of where the drain spout is located? i like the idea of attaching a 1/2' clear hose to it and draining it out that way. i just dont know where the drain spout is located at, a picture of it would help me out the best


lower driver's side corner of the radiator


----------

