Coolant for a MK2 Scirocco

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Elliot-L
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Coolant for a MK2 Scirocco

Post by Elliot-L »

Hi all,

Got a bit of a weep on my radiator so I've got a new one ordered ready to drop on next weekend. I'm under the impression that cars this old should be using blue G11 coolant whereas mine has currently got pink in it.

I've had a quick look on the Halfords website and they sell Comma G48 which is listed as suitable for VAG up to 1996. I'm guessing G48 has just superseded G11 but does anyone know for definite? Car's a 1988 1.6 if it makes any difference. Thanks.

Elliot.


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james butler
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Re: Coolant for a MK2 Scirocco

Post by james butler »

i just used the blue ready mix stuff from euro car parts but whatever you use make sure you flush out all the pink thoroughly before you put anything else in there other wise it will turn to sludge and block everything up.


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Re: Coolant for a MK2 Scirocco

Post by Elliot-L »

james butler wrote:i just used the blue ready mix stuff from euro car parts but whatever you use make sure you flush out all the pink thoroughly before you put anything else in there other wise it will turn to sludge and block everything up.
Cheers, yeah I'll run plenty of flush through it when I do it.


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hiltow
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Re: Coolant for a MK2 Scirocco

Post by hiltow »

You need to get rid of the pink G12 coolant that you have asap and make sure that you back flush the rad, engine and heater to rid all traces if it. If you don't, then the correct blue coolant will react with it and form a sludge in the cooling system. Comma G48 Xtreme Green is the correct stuff, which is to the VW G10 / G11 spec.

Pink OAT coolants are made for modern engines with tightly sealed coolant systems. Modern engines run with less coolant that old ones, which is where these coolants come in - they're good at keeping engine temps down as they have a lower boiling point. However, they are also very good at finding leaks and rotting old hoses in older-designed systems like ours, which is why you've got a leak in the first place. Need to get rid quick!


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Re: Coolant for a MK2 Scirocco

Post by Elliot-L »

hiltow wrote:You need to get rid of the pink G12 coolant that you have asap and make sure that you back flush the rad, engine and heater to rid all traces if it. If you don't, then the correct blue coolant will react with it and form a sludge in the cooling system. Comma G48 Xtreme Green is the correct stuff, which is to the VW G10 / G11 spec.

Pink OAT coolants are made for modern engines with tightly sealed coolant systems. Modern engines run with less coolant that old ones, which is where these coolants come in - they're good at keeping engine temps down as they have a lower boiling point. However, they are also very good at finding leaks and rotting old hoses in older-designed systems like ours, which is why you've got a leak in the first place. Need to get rid quick!
Thanks for the reply. That's what I feared, although I wasn't aware that they could react together! That's the job for next weekend then as long as the new rad is here. Will certainly make sure to put plenty of engine flush through and some fresh water until it's all running clear before I put the fresh coolant in then. Thanks for the help.


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Re: Coolant for a MK2 Scirocco

Post by mark1gls »

I use this stuff, it does need changing every 2-3 years.
http://www.eurocarparts.com/ecp/p/car-a ... &0&cc5_865

5L is plenty.
Others do seem to run the pink VW G13 coolant and have no problems with it but it's up to you.


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Elliot-L
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Re: Coolant for a MK2 Scirocco

Post by Elliot-L »

mark1gls wrote:I use this stuff, it does need changing every 2-3 years.
http://www.eurocarparts.com/ecp/p/car-a ... &0&cc5_865

5L is plenty.
Others do seem to run the pink VW G13 coolant and have no problems with it but it's up to you.
Saw that stuff when James mentioned ECP, much cheaper than the Comma from Halfords even with a trade card. As long as it's trouble free, I'd rather use the proper blue stuff. I've no idea what's currently in the car, just that it's pink. Cheers


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Re: Coolant for a MK2 Scirocco

Post by ThomasD »

VW's position is the new G13 is fine for older cars. I run it in my Scirocco and there are no problems. I think if you've got a leak, it's going to leak with whatever coolant you put into it to be honest as the system is under considerable pressure when hot. Like oil, people have a lot of opinion about coolant. I've seen lots of posts claiming G11 causes corrosion in cylinder heads. And posts that say it doesn't. And the posts the say G12 was introduced to fix corrosion issues. And others which say it is not good either. Regardless, VW's position is even for Mk1 cars, G13 is appropriate.

My advice is to run whatever you like - it is more important that you thoroughly flush the system and then periodically refresh whichever coolant you choose.

BTW, here is a nice link to some cooling info for Mk1 Cabrios, but much of it applies to our cars too: http://www.cabby-info.com/cooling.htm

Tom


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Elliot-L
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Re: Coolant for a MK2 Scirocco

Post by Elliot-L »

ThomasD wrote:VW's position is the new G13 is fine for older cars. I run it in my Scirocco and there are no problems. I think if you've got a leak, it's going to leak with whatever coolant you put into it to be honest as the system is under considerable pressure when hot. Like oil, people have a lot of opinion about coolant. I've seen lots of posts claiming G11 causes corrosion in cylinder heads. And posts that say it doesn't. And the posts the say G12 was introduced to fix corrosion issues. And others which say it is not good either. Regardless, VW's position is even for Mk1 cars, G13 is appropriate.

My advice is to run whatever you like - it is more important that you thoroughly flush the system and then periodically refresh whichever coolant you choose.

BTW, here is a nice link to some cooling info for Mk1 Cabrios, but much of it applies to our cars too: http://www.cabby-info.com/cooling.htm

Tom
Thanks for the link Tom, that's pretty handy!

Wether or not the coolant caused the leak in the rad I've got a new one on order. The one on the car now looks to be original so I'm surprised it's stayed solid this long! Either way I'll fully flush the system when I swap the rad at the weekend. Thanks.


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Re: Coolant for a MK2 Scirocco

Post by GTXTRA »

I'm switching to a combo of the waterless forlife stuff or the G13 across mine.
Had assumed the blue was fine but if you check my Scala project thread look at the state of the cylinder head as discovered this year.
My regular spanner men, the Phirm, concur the g13 is fine on these cars once fully flushed.


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Elliot-L
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Re: Coolant for a MK2 Scirocco

Post by Elliot-L »

GTXTRA wrote:I'm switching to a combo of the waterless forlife stuff or the G13 across mine.
Had assumed the blue was fine but if you check my Scala project thread look at the state of the cylinder head as discovered this year.
My regular spanner men, the Phirm, concur the g13 is fine on these cars once fully flushed.
Seems to be a case of lots of different opinions on this then. Looks like a case of make sure it's had a proper flush as the main point and pick a favourite colour! :hehe:


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Re: Coolant for a MK2 Scirocco

Post by Nate »

ThomasD wrote:VW's position is the new G13 is fine for older cars
Where did you get that from? Previous enquiries with them (and the label on the last bottle I looked at) said that g13 was NOT backwards compatible and must not be used in engines.not designed to take it


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Re: Coolant for a MK2 Scirocco

Post by james butler »

Vw also state that 5/30 oil is the recommended oil to use
Hmm I don't think so.
The different coolant types are also used in relation to all alloy engines or part alloy part cast iron or all cast iron engines so be very careful what you use.
Unless like gtxtra your goin to use for life coolant (which I would recommend) stick to the simple blue coolant I mentioned.
At the end of the day it's coolant so anything wet will do but it's important it has the correct anti corrosion properties compatible with the period gaskets and materials.
Hence all the different types.


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Re: Coolant for a MK2 Scirocco

Post by ThomasD »

Nate wrote:
ThomasD wrote:VW's position is the new G13 is fine for older cars
Where did you get that from? Previous enquiries with them (and the label on the last bottle I looked at) said that g13 was NOT backwards compatible and must not be used in engines.not designed to take it
Volkswagen UK's technical support team responded to an email I sent them a year ago asking if G13 was appropriate to use in a 1984 Scirocco and they specifically said it was compatible. Not that you should believe everything you read on the Internet, but many VW sites (ECS, the link I posted above), suggest that owners of older cars may want to consider moving to G13 if they are doing a complete cooling system flush. Also, the application guides I've seen for G13 list all watercooled VWs, including Mk1s.

Again, I'm not suggesting G11 or G12 is bad. I'm just saying that VW states, and I have no reason to doubt them, that G13 is perfectly fine for older VWs.


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Re: Coolant for a MK2 Scirocco

Post by hiltow »

The G13 (or any Organic Acid Technology) pink coolant performs far better at its job than the old 'blue' G10/11 coolants - your engine will run slightly cooler in use....but that's where the benefits end for vehicles with old-design engines and cooling systems like ours.

All antifreezes / coolants are good at finding their own leaks in any system. However, OAT-based coolants are much more aggressive in this respect, so don't be surprised if when using it you start to get leaks at hose joints that you didn't have before. This is exactly what happened when I tried it once in mine a few years back. Changed back and never had any no problems since.

I've also heard that over time they can degrade rubber hoses and brass fittings and aren't recommended for use in older vehicles. Personally, I don't think it's worth the risk.


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