Coolant Flush

I've been dismantling an AHU from a '98 Jetta to use in my tdi swap and when I emptied the coolant system things didn't look very good. It looks like the previous owner had either mixed G12 and green coolant or there is alot of rust in the system. The coolant was greenish with a heavier red sediment that settled to the bottom. Also there was a good deal of plastic/rubber fragments in the fluid.
Any ideas what all this could be from?
So I want to flush whatever remains out of the engine. Is there a way of doing this without running the engine? The motor is still in the car but the radiator has been removed.
Is there a recommended coolant flush additive?
Thanks again!

The car had been sitting for several months outside prior to me buying it. Could this be a factor?

That's not a good sign. While you're in the process of doing your swap, install a new water pump and heater core. You don't want to have to do the heater core a couple of months after you finish the engine swap, and the part itself is very inexpensive.

I'll go out to the garage in a minute to see what kind of coolant flush we have out there. It seems to work pretty well. Make sure that you use plenty of water to flush after doing the chemical flush.

Why do the heater core, do you know what kind of work is involved in replacing that?

Flush the heater core, but don't remove it unless it's leaking.

Because it's easier to do it while in the middle of the swap than to do it after the swap is complete.

Yes, I do know what kind of work is involved in it - first hand, which is exactly why I'm telling him to do it now rather than later.

The engine is getting pulled from it's present location and reinstalled into a B3 Passat. I'm not worried about the present heater core, I just want to clean out the engine itself and remediate any damage. I'm going to do a full timing belt/water pump job before reinstalling it.
I'm thinking I'll hook up the engine to a hose and flush it with hot water, then reinstall the radiator and wiring harness to run it with a coolant flush before draining and flushing it one last time.

Oh nevermind... I thought you were talking about the car that the engine was going into for some reason.

So, it really is true that mixing pink and green makes cottage cheese? I had wondered if that was just another way VW blackmailed us into buying normally cheap consumables like anti-freeze at the dealer. I'd be interested in seeing pictures of the precipitate, just out of morbid curiosity.

I'll take some pictures of it, it sure isn't pretty.
Anyone know what the particulates in the coolant could be from or caused by? They aren't metallic but black rubber/plastic. I should probably change all the coolant hoses/fittings?
I'm just hoping the headgasket is ok. Compression came in between 360-390psi, on a slightly warm engine.

Did that year have the plastic water pump impeller? That'd be my guess.

Looks like what we have out in the garage is the Prestone Coolant Flush. I thought it was something different... not sure how well it works.

Could be the plastic impeller or the hoses and flanges deteriorating. Pink + Green makes for some really nasty stuff. Pull the hoses off and have a look inside. Run your finger around the inside and see what comes out. If it's really gross, I'd go ahead and replace the coolant hoses with new ones.

Isn't all antifreeze basically ethylene glycol and water? What did VW put in the pink stuff that makes it so reactive with other antifreeze? I looked all over (well, I tried NAPA, Car Quest and Checker), and couldn't find any antifreeze that said G12 on it. I found some Pentofrost SF, or something like that. In a white 1.5 litre jug. It said VW on it, but it didn't say G12, so I passed.

You can't buy G12 at any local auto parts place. Same goes for Ford Motorcraft coolant. Auto parts stores will claim that a lot of their products will work universally, but you have to be careful, especially with the diesels (specifically with cavitation on the PowerStroke).

Cadman1940

Hey guys the junk in bottom of cooling system is from sulfuric acid build up in block. I have and do still use a cooling system conditioner made by BG products that moves the system from acidic to alkaline on my caddy in just a 12 oz app 1 to 2 times a year. I have a garden PH meter I found at Harbour freight for about $5 and checked against litmus strips that I have and sure makes it easier to and quicker to check coolant. If you mantain ph balance you will never have a radiator or heater core go bad from corrosion. Start this on a brand new vehicle and you can run it till the wheels fall off and cooling system will still be clean and nice. Go to a big truck shop and talk to the better mechanics there and you will find that they will tell you the same thing about not needing to boil out the block on a rebuild. Thanks Eric 03 jetta 40M & 00 cabrio 44M

Conan said:

So, it really is true that mixing pink and green makes cottage cheese? I had wondered if that was just another way VW blackmailed us into buying normally cheap consumables like anti-freeze at the dealer. I'd be interested in seeing pictures of the precipitate, just out of morbid curiosity.

Click to expand...

Because G12 is far superior to the green coolants we had 20+ years ago. Pull apart a 10+ year old coolant system that had G12 and it will still look like brand new.

Hey card man,

i'm about to do a flush on my passat and came across this youtube video on BG super coolant.
http://www.youtube.com/watch?v=cfC5r4HLx5k
Where can I purchase this stuff?

Chris

VeeDubTDI said:

You can't buy G12 at any local auto parts place. Same goes for Ford Motorcraft coolant. Auto parts stores will claim that a lot of their products will work universally, but you have to be careful, especially with the diesels (specifically with cavitation on the PowerStroke).

Click to expand...

Pentofrost's website says that Pentofrost SF is a G12 coolant. I get mine at napa. Never had any problems with it.

Pentofrost by Pentosin (German) is G12 and VW-compatible. It is purple in color, and sold in most local parts stores (O'Reilly AKA Kragen's on the west coast has it). 5 liters costs about $50 so you might as well buy the original VW stuff.

Conan said:

Isn't all antifreeze basically ethylene glycol and water? What did VW put in the pink stuff that makes it so reactive with other antifreeze? I looked all over (well, I tried NAPA, Car Quest and Checker), and couldn't find any antifreeze that said G12 on it. I found some Pentofrost SF, or something like that. In a white 1.5 litre jug. It said VW on it, but it didn't say G12, so I passed.

Click to expand...

Yes, Pentofrost SF is G12.

jujujulia said:

Yes, Pentofrost SF is G12.

Click to expand...

you do realize you responded to a five year old post.