VW Beetle Forum banner
1 - 4 of 4 Posts

·
Registered
Joined
·
15,839 Posts
Discussion Starter · #1 · (Edited)
re: g12 and green coolant contamination! How to clean the system?

Hey, guys! I am working on a horribly neglected 2003 Jetta with a AVH 2.0L. Car came in for drive-ability issues (coil grounding code; ran new ground wire as per service bulletin) and then found out ; when I took it for a test drive, the car over heats! When I pulled the thermostat, the plastic water pump impeller was cracked (as usual!). Ordered a w/p and timing belt kit from Blauparts; the parts showed up today.

Meanwhile, when i waiting for parts; I was fixing a leaking coolant flange and was trying to flush the cooling system. After awhile; it became apparent, that someone had mixed g12 and regular coolant in the system at some point, the car had been leaking coolant for so long... all that was left was oxide red, rusty water! When I started looking at the flanges, the coolant bottle (stuff/residue inside) and other hoses, a gooey reddish yucky, slimy residue was on some parts. I have read about incorrect coolant contamination for years but have never seen it before (now I know, first hand!). I have flushed the system with water; even tried some dish soap but aside from pulling every hose and running bushes through everything and taking the radiator to a radiator shop for a rebuild/clean out, I don't quite know what to do. The customer is broke, doesn't have the money to replace everything and I have a feeling, I am going to have to clean and flush, the best I can and call it a day... hope for the best! From what I can tell so far; it looks like the gooey stuff, is more in the higher coolant level parts (bottle, upper hose connected to the bottle etc.). Of course; I cannot see inside everywhere the coolant goes but the block where the thermostat/waterpump are; doesn't seem to have much slimy red stuff in there.

Has anyone; tried anything that removed all the continuation or just flushed everything as best as possible and moved on? I think it will be ok but am little worried about clogged passages and if the water pump will fail prematurely; have issues with not getting lubricated as it should or the contamination harming it in some way. Any experiences or advice appreciated! Thanks!

PS: I have taken many hoses off and run water through them; so far, it seems nothing is clogged, as far as I can tell. I took the one hose that connects to the coolant bottle and ran a pipe cleaner with dove dishwashing liquid and it removed the gooey stuff and after scrubbing with the brush... finally came clean. If I did this with all the hoses, orifices, passages, etc.; I would be cleaning for days! Replacing everything; would probably be the correct thing to do but with this customer, it just isn't in the cards! :cry:

 

·
Certified Arcade Tech
Joined
·
416 Posts
Best way I can think would still be flushing it out with a garden hose. (to expensive to use distilled water...and tap water won't hurt a thing for flushing)

I'd start by removing the thermostat and reattaching the housing.

Pull a radiator hose Point it into a recovery bucket if there is still antifreeze crud in it (just to keep the EPA happy :D )

I'd pull a heater hose and start back flushing from there. Then switch over to the feeder hose from the expansion tank, reattach the heater hose....kick the water on... Then just unhook the other radiator hose, and shove the garden hose into it...and let it rip!

Then again you've probably already done all of this....But that's how I flushed ours out. One thing not recommended I found is the use of any "flushing agents". Due to their acidic nature. Maybe something very "gentle" like Vinegar introduced? Once watered down a bit it might be just enough to scrub out the ****---and easier to flush out when done. (The aluminum and the seals of the water pump do not like the usual flush agents--so that makes this task a lot harder then it should be)

Please let us know how you make out. Oh....Pictures of the 'gunk' would also be helpful. I still talk with people that swear just because the bottle says it's okay to mix coolant? They see no issue.

S-
 

·
Registered
Joined
·
15,839 Posts
Discussion Starter · #4 ·
I ended up flushing the system about 5 times and taking the top most small hoses and scrubbing them out, with dish washing liquid and small pipe cleaner, blew them all out with compressed air and got clean water coming out of the engine after all the flushing. After the timing belt and waterpump swap, all new belt path components, coolant temp sensor, serpentine belt, new thermostat, (2) new coolant flanges, a new heater connection at the firewall, etc.,; I put in fresh Pentosin SF and distilled water @ 50/50. Car was solid, ran good, no overheating and the temp gage was straight up in the middle; took it for a long test drive and everything seemed fine, no leaks, fans came on when they should and we sent the Jetta on its way. If I had access to some professional cleaning/recycling system; I think I would have done some more cleaning. As it was; I did the best I could with the limited resources I had. As per the Blauparts page; I was concerned about the cleaners hurting the new waterpump; so, I just flushed with water only.
 
1 - 4 of 4 Posts
Top