Can you Flush and Refill All Coolant from 2010 TDI CJAA Without Removing Hoses?

gmcjetpilot

Veteran Member
Joined
Aug 18, 2008
Location
Memphis TN
TDI
2010 JSW TDI DSG Matalic Grey
So I had my system flushed. I was going to do it myself as I do all my routine maintenance (oil filter changes, engine, DSG, fuel, air), but this looked like a big PIA.

I picked it up and it had purple pink stuff in reservoir. So far so good. The price was higher than expected. Don't care as long as I get good service. The shop has always done me right. Going there for over 6 years.

I asked the owner how do they flush it? I was shocked to hear they don't remove any hoses!!!! He mentioned special fitting they put on the reservoir, running it gets to full temp. I asked about using tap water or distilled. The answer was they use a pre 50/50 mix. I don't want to bother them with dumb questions. CAN ANYONE EXPLAIN THIS VOODOO MAGIC. How do you get all the fluid out even with a super fitting and vacuum on the reservoir??? Not sure what they flushed it with, distilled water or a garden hose from the tap.

Can vacuum remove all fluid from the system by reservoir cap?
If they are adding 50/50 then the system has to be empty to get correct ratio?

Please explain? I know from reading the Forums the tried and true DIY method is remove one radiator hose, remove a oil cooler hose and drain. Connect the hoses, refill with distilled water and run. Repeat this over and over until it comes out clean. Last time drain and fill with 100% G13. Since the system can only be drained about half by removing hoses this works out well......
 

gmcjetpilot

Veteran Member
Joined
Aug 18, 2008
Location
Memphis TN
TDI
2010 JSW TDI DSG Matalic Grey
Why didn't you ask to see the tool and how it works?
That is genius, but.....
1) I am trying to be diplomatic
2) No customers are allowed beyond fence line, in building or service bays. This thing called Covid19. You might of heard about it.
3) I talked to him twice.... I don't think I am going to hear anything different.
4) There is a service tool on Youtube that shows a device like this:
https://youtu.be/DQcZk_vqPmY?t=5 First 2 minutes
https://youtu.be/DQcZk_vqPmY?t=1067 How to Use It
The issue is this video shows he pulls hoses. Obviously this is not the magic tool as described to me.

However I thought you knew everything.... Research this and get back to me. Ha ha :D

It is possible I misunderstood about not removing hoses? I have an almost 7 year relationship with this independent VW, Audi Porsche shop. I care about good relationship with the two owners.... Tech who worked on my car (I think) not a fan of. He use to be at the dealer. Long story. However the owners watch all the services and are very experienced. How can you screw up a flush? Ha ha. I am sure many ways.

Some choices:
Talk to the dealer and ask if they have some special vacuum sucker out'er.
Suck out the reservoir down evertime I fill up with fuel and replace with 50/50 G13. Over time and two gallons of 50/50 I should have righted any wrongs if there are any wrongs to right.
Demand the shop show me how and what they did it. I am not there yet.
Not worry about it.
Wait for your research and answer....
 
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oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis (where it's safe)
TDI
There are just too many to list....
I would not hesitate to show any of my customers how I did something. I even invite them to watch me if they really want to. I most recently had some guy not understand how I could R&R a transmission without touching the outer CV joint bolts. The answer was that I simply remove the drive axles from the transmission and suspend them out of the way, and if he wanted to, I would be happy to show him OR he could wait until the next one and I'd call him up and he could come see. I did. He did. And now he is happy.

There are vacuum operated devices for FILLING a cooling system that is empty (or nearly empty). Works more or less just like the A/C system. You pull a vacuum on it through the fill cap, then a tube is inserted into a jug of [premixed] coolant, open a valve, and the vacuum pulls the coolant into the system. But it is not the same as a flush. It cannot remove coolant.

The flush machine requires hoses be removed.

I have both devices.

If you asked this person how this works, and you got flak from them, you do NOT have a "good relationship" it would seem. Because if they honestly had some such device, they'd certainly have no problem showing you how it works, or at least showing or even telling you what the tool is, as I am sure you could find some video on how it works.
 

SilverGhost

Veteran Member
Joined
Mar 25, 2005
Location
Back in So Flo - St Lucie
TDI
'05 Golf - totaled :(, wife's '13 Beetle - buy back, TDIless
Having worked at a Chrysler dealer before starting my 15 years with VW I can tell you there is a "flush" device with a couple tanks that claims to do a complete system exchange through the pressure cap. More accurate would be to call it a coolant service station to drain and fill system.

In my experience, even when new, you were lucky to get more than 1/2 of the system capacity out. But done on a regular basis you replaced a large chunk of the coolant with fresh additives and remove contaminates.

That said there is no pull a hose and drain the whole system on a new VW like the Common Rail or any TSI. Heck, you need a scan tool to actuate the thermo valves open and program the coolant pump to purge mode. After trying to flush the junk when changing a heater core I can tell you its hard to get all of it out.

Jason
 

gmcjetpilot

Veteran Member
Joined
Aug 18, 2008
Location
Memphis TN
TDI
2010 JSW TDI DSG Matalic Grey
Thanks everyone great replies.

I called the VW dealer and talked to an actual tech (not service writer) and he said the same thing. He knew exactly what I was talking about. They have the same thing that attaches to reservoir. They run the engine and and force fluid in and control and capture coolant from overflow tube. They force 50/50 mix in, let engine run, and keep doing that for a while. Obviously the old and new coolant will mix, but if "flushed long enough" you end up with cleaner refreshed coolant.

I asked the dealer Tech if the wrong stuff was in the system how do you get it all out. He admitted you can't you need to remove hoses. He also acknowledged the PIA design of lower hose half way up the radiator and no drain.

My conclusion - The VW service and what was done at my favorite independent shop is NOT a flush. It's a REFRESH never flushing or removing all of the old stuff just diluting it with new stuff.... That may be adequate for a clean system. However if you want 100% of old stuff out, forget it.

Basically you can achieve the same thing by sicking the reservoir down and refilling it with fresh mix.... repeat periodically. I have 8 liters of 50/50 G13. I am going to do this... it can't hurt and will make me feel better.

The method of removing lower (mid way up) hose and oil cooler hose, putting hoses back, putting in distilled water, run... remove hoses again, reinstall, refill, run, repeat many times until it stays clear.... last time you drain fill with 100% coolant.

There is a market for an aftermarket radiator with a drain plug at the bottom....:D
 
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SilverGhost

Veteran Member
Joined
Mar 25, 2005
Location
Back in So Flo - St Lucie
TDI
'05 Golf - totaled :(, wife's '13 Beetle - buy back, TDIless
GMCJETPILOT said:
There is a market for an aftermarket radiator with a drain plug at the bottom....
No there is NOT. The cooling system is an incredibly complex maze of hose, pipes, coolers, valves, thermostats, pumps, and heat exchangers on a modern TDI. A drain on the radiator is going to miss A LOT of the cooling system, and the debris therein.

Only way you are getting 100% flush involves the engine basically down to a long block, and most of the engine bay spread out over a shop floor where you then proceed to use a hose to flush water through everything.

I had a customer think the blue coolant cap was the AdBlue cap on a 2010 Golf. Many flushes later the system still had DEF in it. That's the point when we did ^^ and managed to get it clean enough. Though I did suggest much more frequent coolant inspection and change schedule.

Jason

PS: I think the "drain and fill" is a good idea on a regular basis to keep fresh coolant (and its additives) in the system. Which is the point of the vacuum "flush" device.
 

SilverGhost

Veteran Member
Joined
Mar 25, 2005
Location
Back in So Flo - St Lucie
TDI
'05 Golf - totaled :(, wife's '13 Beetle - buy back, TDIless
I flush a TDI cooling system by removing the passenger radiator hose and BOTH intercooler hoses (Passat and 15 TDI) OR the oil cooler hose. Put hose in the top intercooler pipe and wait for clean water at lower pipe, continue for 5 minutes. Repeat on radiator hose. Then park the car over a drain and let it idle for at least 45 minutes, sometimes longer, with a hose in the reservoir and both lower hoses off (sometimes prop intercooler hose against intercooler pipe to slow water flow so it comes out radiator as well).

Two thirds of the time that works to clear the system out when the heater core has been plugged. Rest of the time we parts warranty a heater core when it comes back again. Repeat the flush regime again.

Like I implied - not an easy engine to flush the coolant.

Jason
 

gmcjetpilot

Veteran Member
Joined
Aug 18, 2008
Location
Memphis TN
TDI
2010 JSW TDI DSG Matalic Grey
I flush a TDI cooling system by removing the passenger radiator hose and BOTH intercooler hoses (Passat and 15 TDI) OR the oil cooler hose. Put hose in the top intercooler pipe and wait for clean water at lower pipe, continue for 5 minutes. Repeat on radiator hose. Then park the car over a drain and let it idle for at least 45 minutes, sometimes longer, with a hose in the reservoir and both lower hoses off (sometimes prop intercooler hose against intercooler pipe to slow water flow so it comes out radiator as well).Jason
You are flushing with tap water? Then you run it with hose's off? Hummm. Tap water is no good due to mineral deposits. Running open unpressurized system could result in parts of system with air, resulting uneven cooling that could damage engine.

No there is NOT. The cooling system is an incredibly complex maze of hose, pipes, coolers, valves, thermostats, pumps, and heat exchangers on a modern TDI. A drain on the radiator is going to miss A LOT of the cooling system, and the debris therein.
As far as a radiator with drain like most other VW's, you say no good because you won't get debris out? What debris? The debris is small and in solution. Repeat drain and fill would rid the system of debris as you call it. Second if VW move the lower radiator hose to bottom of radiator it would help.
 
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gmcjetpilot

Veteran Member
Joined
Aug 18, 2008
Location
Memphis TN
TDI
2010 JSW TDI DSG Matalic Grey
I took my brand new jug of G13 and I made a 50/50 mix. I sucked all the reservoir down and put into a clear plastic jug. It look perfect, clean, pink purple color. It was the same color as my brand new fresh coolant. I felt good about that. I went ahead and re-filled the reservoir up with new coolant mix.

One thing I noticed was in the reservoir it has a little different look. In the reservoir than it does look less pink purple, from being in clear glass or plastic container. I'm starting to think my original coolant which I thought looked orangish was okay.

Long story short I think whatever they did was good enough because the coolant I removed looks clean and proper color. I'll just do the reservoir vacuum and fill once in awhile keep it fresh and stop worrying.

PS The car is running about 7 degrees cooler. Normally before flush ran at 188. Now running at 181 on a hot day freeway speeds.
 
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