Volkswagen Passat Forum banner

1 - 20 of 21 Posts

·
Moderator/Administrator
Joined
·
24,745 Posts
looks nice. My flange failures were due to the o-ring deforming over time though. You still will have to worry about that.
 

·
Registered
Joined
·
5,335 Posts
If my flange failed, that looks like a nice replacement and the price is excellent.
 

·
Registered
2004 GLS 1.8T
Joined
·
12,142 Posts
My flange JUST got replaced, and I wish I'd known about the aluminum one. Of course, the plastic one lasted 125,000 miles...
 

·
Registered
Joined
·
27,572 Posts
That is new. I was looking at the transverse billet and cast flanges. They can be had without the heater hose outlet, but the trans cooler outlet would work fine (without the clip on hose connector. They also use the B6 style rubber connector (with clamps) between the metal pipe and flange (have to change to a B6 metal pipe, maybe more).

The O-ring deforms due to the inner plastic retainer rotting away, this would avoid that and it would be unlikely you would own the car long enough for just the rubber to degrade and leak.

As I would like to eventually move the coolant tank to the battery area (after a battery relo), I have to look into this further.
 
  • Like
Reactions: wormybeech

·
Registered
Joined
·
877 Posts
I'm on my fourth flange. The flange itself doesn't fail, it's the O-ring that seals it to the engine block. The cost of the flange and the associated parts are dirt cheap so I just replace all of them when it starts leaking when in reality all I'd really need to do is replace the O-ring. A $50 aluminum flange seems like overkill to me. I think I paid less than $10-15 for a new flange, all O-rings, plug, and clips for the plug and temperature sensor. Even with the aluminum flange you're going to have to replace the main O-ring again at some point.
 

·
Registered
Joined
·
54 Posts
I agree with PZ on this. If the integrity of the inner plastic lip of the o-ring home could be preserved, the o-ring wouldn't fail. The aluminum model would take care of this.

Sent from my XT907 using Tapatalk
 

·
Registered
Joined
·
877 Posts
I've never had a leak occur between the hard pipe and the flange. It's always been between the flange and the engine block. I've never noticed any deterioration of the plastic on the flange itself. Leaks that occur at the hard pipe interface are more likely due to improper installation, causing the O-ring to get pinched or not being seated correctly.
 

·
Registered
Joined
·
27,572 Posts
I've seen leaks at the hard pipe connection on 2 different cars. They were on the original flanges, the seal just shrank too much.
 

·
Registered
Joined
·
877 Posts
I've seen leaks at the hard pipe connection on 2 different cars. They were on the original flanges, the seal just shrank too much.
OK. Still, I'd have to weigh the advantage of spending $50 for an aluminum flange vs. just a few bucks for the plastic one. The seals are going to fail at some point regardless of the type of flange or their location, which you just confirmed.
 

·
Registered
Joined
·
877 Posts
usually with a metal to metal connection you would have a " gasket " not an O ring .
Not likely with the hard pipe connection. I can see it with the flange to block interface, though. Unfortunately, it clearly has a channel for an O-ring and it shows two O-rings that are supplied with the flange, which means you'll most likely still be plagued with the same problems as the original plastic flange. However, I do like the idea of using a gasket instead.
 

·
Registered
Joined
·
4,817 Posts
Nooooo! $49.99 is a Chinese price for this painted plastic part... :hmmm: ;)

If the tooling costs were factored in, the actual cast part if it even existed (what's shown in the above link doesn't) would be well over ~$100.

Saw this on Audizine about 3-4 weeks ago. :crazy:

13 posts...damn!
 

·
Registered
Joined
·
27,572 Posts

·
Registered
Joined
·
528 Posts
Count yourself among an extremely small minority. A leaking coolant flange is just one of those things that Passat owners have come to accept as a routine failure along with failed ABS modules, oil sludge, and worn control arms.
That is a good run indeed..!!

My 04 1.8T is finally starting to leak pretty decently from the coolant flange at 160,000 miles, and I am now starting my daily regime of arm-dislocating exercises in preparation of tackling the flange replacement.

I am (fingers crossed, no jinx no jinx) still on my original ABS module, original control arms and no evident sludging.
 

·
Registered
Joined
·
877 Posts
I have also been fortunate in that I have never had to deal with the sludge issue in my '99 1.8T. I owe it to the info I culled from this forum on the subject and thoroughly cleaned my engine with AutoRx before switching to all synthetic 5w40 oil. You might want to check your control arms for wear because you probably won't know they're shot until they fail. The uppers tend to go out well before the lowers. You might want to see if you can get the upper pinch bolt to come out even if you don't need to replace the control arms yet. At some point it will have to be removed and, the longer you wait, the harder it will be to get it out. Liberally coat the shaft with anti-seize compound before reinstalling it and it will come out quite easily the next time.
 

·
Registered
Joined
·
459 Posts
Wish I had bought this when I did the flange on our Passat about a year ago. The O-ring was in good shape but there was a very small crack in the plastic that was causing the leak. I suppose I'll just put the aluminum one on the next time the flange goes out...I'll prolly have the car long enough.
 
1 - 20 of 21 Posts
Top