orange/brown gunk in cooling system

[Ameer Antar]

Well, I never put in the green coolant myself, although there was some in there
from the po. After replacing almost every single component in the system, I
figured I wouldn't have to flush anything out. That included the engine,
radiator, heater core, hoses, pipes, transmission cooler, etc.
 
I used the blue stuff from Pentosin, which is supposed to be the recommended
coolant for the early type 44's. This is not the cheap stuff you can at the
FLAPS. The weird thing is the coolant used to be blue, but after only a few
months it turned orange/brown. I never put anything else in there, so that got
me worried. Seems like it's rust or something like exhaust is making it turn
colors. I don't think any type of coolant should do that in such a short time.
I guess I'll just have to wait and see what happens this time. Hopefully this
was just related to the loose head studs.
 
Thanks for the tips everyone. I'll keep you posted.
 
-Ameer 


-------------------- Original Message --------------------
From: Pantelis Giamarellos [pantg at otenet.gr]
To: 'Ameer Antar' [antar at comcast.net], 'Quattro List' [quattro at audifans.com]
Date: 3/13/07 1:37:01 AM
Subject: RE: orange/brown gunk in cooling system

 > Ameer Hi,
>
> Mixing the blue/green coolant with the orange one is an absolute NO NO.
>
> Even when you completely replace one type with another and first clean
> thoroughly with water it is supposed that you have to use a special
> coolant system cleaner and neutraliser before filling up with the
> different type of coolant in order to be able to do so.
>
> We have the same problems with Land Rover vehicles and according to the
> instructions provided by the technical director of LR here in Greece
> those are the things that you have to keep in your mind.
>
> 1. NEVER MIX blue/green with orange coolant.
> 2. ALWAYS USE the cleaning/neutralising liquid when you perform such a
> change on your cooling system.
> 3. NEVER use tap water with blue/green coolant.
> 4. NEVER use de-scaled or distilled water with the orange coolant. This
> orange coolant is ORGANIC and tap water provides it with its nutritional
> elements (in plain english tap water is its food)
> 5. NEVER keep the orange coolant for more than two years on a used car
> or five years on a new car. It is even better to change it more
> frequently than that.
> 6. If you use orange coolant and the cooling system overheats too much
> it is better to change it.
> 7. The organic orange coolant leaves a very thin layer on the cooling
> system's surface. This actually stops electrolytic corrosion which is a
> known problem of mixing different types of metals and alloys, something
> very common nowdays.
> 8. When the organic coolant dies the thin layer transforms into gunk
> which blocks coolant passages inside the engine and radiator and this
> results into the overheating problems and what you have seen as
> orange/brown gunk.
>
> All the above is valid for LR engines but I think it makes perfect sense
> to also be applicable on other manufacturers engines.
>
> HTH
>
> Take care
> Pantelis
>
>
> -----Original Message-----
> From: quattro-bounces at audifans.com [mailto:quattro-bounces at audifans.com]
> On Behalf Of Ameer Antar
> Sent: Tuesday, March 13, 2007 4:15 AM
> To: Quattro List
> Subject: orange/brown gunk in cooling system
>
>
> Hi All, I've got a new mystery for you. This is from my '85 5kt with
> less than 7k since restoring it...
>
> So I had to replace the radiator fan switch this weekend because the
> low-speed part flaked out. When I was in there I noticed some
> orange/brown mud on the sensor and in the radiator hoses. The coolant
> also looked the same. I was surprised because I replaced the coolant
> with the blue stuff in October. Everything is new in the system, except
> the reservoir. The engine was rebuilt and first run in June, and I
> replaced/cleaned out all hoses, even the transmission cooler.
>
> I doubt the fan switch dying is related, but it seems a little too young
> to crap out like that. In a way, I'm glad it did to make me notice the
> coolant. So what could be causing the coolant to turn brown after only a
> few months? The only thing I can think of is in Sept. I bent a valve,
> and after replacing the head using ARP studs, I took a little too long
> to retorque the studs. I noticed that coolant was leaking out under the
> head. So could exhaust getting into the coolant cause that? No real
> issues with overheating or frothing reservoir. No water in oil, or white
> smoke in the exhaust.
>
> This weekend I flushed the entire system really well with a garden hose.
> I also ran the engine with the hose connected to the engine coolant
> inlet until the water came out clear. The coolant is looking nice now,
> but I have to keep an eye on it. Is there any way to tell if exhaust is
> getting into the coolant or should I be looking for something else?
> Thanks in advance.
>
> -Ameer