GOLFMK8
GOLFMK7
GOLFMK6
GOLFMKV

Failed Thermostat Housing/Coolant Loss Info Gathering

codypka

Go Kart Champion
Location
New Jersey
I know folks will lose their minds on this but....this sorted the slow loss for me. Mine was leaking from the joint between the water pump and therm housing intermittently. I had it in to the dealer and they pressure tested and of course, no dice. It would only spurt coolant once in a while when hot. Figured at 65K, turbo swapped, etc. I'm almost out of warranty anyway (6/72) on my Sportwagen anyway and I'll have a walnut blast done at some point before 100K...will just have my shop replace it then. However, this has fixed it. It's just a pencil thin gasket between these too parts that is leaking (on mine).

View attachment 224654View attachment 224655
How does this work, you just add it to your coolant tank I presume?

I'm at 76k on my 17 GTI. I suspect I've been losing coolant for a couple years now, being as I had to top it off maybe once a year, despite never being able to physically see signs of a leak. That changed this past weekend when I did an oil change. Now I have definitive signs of leaking. At 76k I assume the dealership won't do crap for me except charge me far too much money to replace. Very frustrating since I don't plan on keeping this car much longer. If not for the shortages in dealer stock, I probably would have already traded it in for something new. I'm tempted to give this product a chance and see if it'll fix the issue for a year or so.
 

Attachments

  • IMG_20220212_100149.jpg
    IMG_20220212_100149.jpg
    4.1 MB · Views: 97
  • IMG_20220212_100315_Bokeh.jpg
    IMG_20220212_100315_Bokeh.jpg
    1.3 MB · Views: 101
  • IMG_20220212_100222.jpg
    IMG_20220212_100222.jpg
    3.5 MB · Views: 98

tigeo

Autocross Champion
How does this work, you just add it to your coolant tank I presume?

I'm at 76k on my 17 GTI. I suspect I've been losing coolant for a couple years now, being as I had to top it off maybe once a year, despite never being able to physically see signs of a leak. That changed this past weekend when I did an oil change. Now I have definitive signs of leaking. At 76k I assume the dealership won't do crap for me except charge me far too much money to replace. Very frustrating since I don't plan on keeping this car much longer. If not for the shortages in dealer stock, I probably would have already traded it in for something new. I'm tempted to give this product a chance and see if it'll fix the issue for a year or so.
Update on my end - the stop leak worked brilliantly for 6 mos. The leak has returned (stop leak products are rarely permanent) and I'm now just out of warranty. I'm having the bits changed out next week and will just keep my receipt/write VW a letter pleading my case to cover it but I'm sure they won't...always worth a shot/writing a letter. I have had no adverse impacts from the product w/r to heater core etc. that is always thrown out as a OH MY GOD THE STOP LEAK WILL PLUG UP YOUR XYZ. I am happy with the product overall. Yes, you dump the can into your coolant reservoir - always follow the direction of whatever product you use. The LM product seems v. good.
 

codypka

Go Kart Champion
Location
New Jersey
Update on my end - the stop leak worked brilliantly for 6 mos. The leak has returned (stop leak products are rarely permanent) and I'm now just out of warranty. I'm having the bits changed out next week and will just keep my receipt/write VW a letter pleading my case to cover it but I'm sure they won't...always worth a shot/writing a letter. I have had no adverse impacts from the product w/r to heater core etc. that is always thrown out as a OH MY GOD THE STOP LEAK WILL PLUG UP YOUR XYZ. I am happy with the product overall. Yes, you dump the can into your coolant reservoir - always follow the direction of whatever product you use. The LM product seems v. good.
Thanks for the reply. I may go the route of trying this product. I figure I don't have anything to lose at this point other than a few bucks. In the meantime I'll get a few quotes. I'll start with my dealer. What's the over/under on the estimate?
 

GTIfan99

Autocross Champion
Location
FL
Thanks for the reply. I may go the route of trying this product. I figure I don't have anything to lose at this point other than a few bucks. In the meantime I'll get a few quotes. I'll start with my dealer. What's the over/under on the estimate?

You also may have better results, if you don't track your car. I believe Tigeo does track, which might make the stop leak fail sooner. Please keep us updated as to how it works out for you.
 

tigeo

Autocross Champion
You also may have better results, if you don't track your car. I believe Tigeo does track, which might make the stop leak fail sooner. Please keep us updated as to how it works out for you.
hahahaha - yeah, I left that out. But it even kept things at bay during the track event last Nov. I think the stuff works, I just think at some point that gasket just fails and no amount of stop leak is going to plug it.
 

codypka

Go Kart Champion
Location
New Jersey
hahahaha - yeah, I left that out. But it even kept things at bay during the track event last Nov. I think the stuff works, I just think at some point that gasket just fails and no amount of stop leak is going to plug it.
I forgot to ask how many bottles you used
 

tigeo

Autocross Champion

ReadTheBook

Autocross Newbie
Location
Bay Area Smoke Hell
Car(s)
DVP Spektrm, MK4 R32
The fact that dealers widely and directly acknowledge this problem and that my replacement motor on my GTI shipped with a brand new thermostat/water pump already with it, makes me so disappointed that VAG haven’t done a full on recall or service extension program AND that people are still having to fight to get this nonsense covered under factory powertrain warranty.

Just pathetic.
 

El_bigote_AJ

Autocross Champion
Location
Las Vegas
Car(s)
2019 GTI bunny
Got me a pump and housing in the mail currently for my car lol. FCPs on back order with no eta for the oe option so unfortunately had to go ecs…

Was going to have the dealer do it, but honestly since I’m going to pull the intake to install the MPI I just bite the bullet sicne I didn’t want to deal with the stress of the dealer touching my car.
 

tigeo

Autocross Champion
The fact that dealers widely and directly acknowledge this problem and that my replacement motor on my GTI shipped with a brand new thermostat/water pump already with it, makes me so disappointed that VAG haven’t done a full on recall or service extension program AND that people are still having to fight to get this nonsense covered under factory powertrain warranty.

Just pathetic.
I don't see it as a recall issue but really the extension program would be nice. The question will always be...while we here in the enthusiast-verse think this happens "to all of them" the real number is probably pretty low overall and that's why it is what it is. Just my opinion of course.
 

StorableComa

Autocross Champion
Location
SoCal, USA
Car(s)
17 GSW S FWD
Is the issue more with the housing leaking, leading to impeller failure? Seems there are no cast thermostat housing for the MK7, but USP does have a metal impeller upgrade for the MK7 -
https://www.uspmotorsports.com/Ulti...w-Metal-Impeller-For-Gen-3-MK7-06L121111.html

I'm currently chasing this down. Had the coolant light come on, topped off, checked it and topped off again. Though since that i've driven to Vegas and back, and put about may 2k on it with no loss. I did have previous signs of crud dripping down onto the oil pan from where the thermostat housing is though prior to this.
 

mopar22

Autocross Newbie
Location
Michigan
Car(s)
16 GTI
Is the issue more with the housing leaking, leading to impeller failure? Seems there are no cast thermostat housing for the MK7, but USP does have a metal impeller upgrade for the MK7 -
https://www.uspmotorsports.com/Ulti...w-Metal-Impeller-For-Gen-3-MK7-06L121111.html

I'm currently chasing this down. Had the coolant light come on, topped off, checked it and topped off again. Though since that i've driven to Vegas and back, and put about may 2k on it with no loss. I did have previous signs of crud dripping down onto the oil pan from where the thermostat housing is though prior to this.
OEM waterpump is metal, the impeller is not the issue https://www.fcpeuro.com/products/audi-vw-porsche-engine-water-pump-genuine-audi-vw-241246
 
Top