Green or Yellow Coolant?

[TiggerToo]

I was going to change the coolant on Tigger's VP MD2030. I see that there are two versions of coolant, one dyed green and one dyed yellow.

1) what is the difference?
2) what should I use?
3) why can't you mix them? (i.e. what happens if you do)
4) what volume of coolant are you likely to have to add if you have a standard sort of calorifier

Thanks in advance for information...

 

[RichardS]

Dozens of threads about this .... but forget the colour and look in the manual to see if Long Life/OAT is recommended or Normal/IAT antifreeze. You then need to check which one of the colours is Long Life (probably yellow) and which one is standard (probably green). You can then use the type recommended by Volvo.

It is not recommended to mix the different types and it is not recommended to not follow the manufacturers recommendation (by definition, I guess) but if you search for other threads with any of the antifreeze key words you will find every shade of opinion.

Richard

 

[Grumpybear]

I was going to change the coolant on Tigger's VP MD2030. I see that there are two versions of coolant, one dyed green and one dyed yellow.

1) what is the difference?
2) what should I use?
3) why can't you mix them? (i.e. what happens if you do)
4) what volume of coolant are you likely to have to add if you have a standard sort of calorifier

Thanks in advance for information...

As a 2030 owner myself:

1 dunno
2 green
3 dunno
4 I think the length of the hoses will affect the extra much more than the heater coil itself. I have just fitted a new calorifier. Refilling about a foot of each hose (overall length about 2metres each) and filling the coil itself took less than a pint of coolant (sorry about the mix of unit systems).

 

[VicS]

I was going to change the coolant on Tigger's VP MD2030. I see that there are two versions of coolant, one dyed green and one dyed yellow.

1) what is the difference?
2) what should I use?
3) why can't you mix them? (i.e. what happens if you do)
4) what volume of coolant are you likely to have to add if you have a standard sort of calorifier

Thanks in advance for information...

The difference is in the inhibitors.

For an MD2030 the traditional low silicate type of antifreeze such as V.P. Coolant ( green) is suitable.
There is no need to use a long life, organic acid technology (OAT) type such as V.P. Coolant VCS ( yellow) unless the engine manual specifically calls for it. It is specified for some of the more recent VP engines.

There is moreover no need to waste money on VP branded antifreeze. A conventional antifreeze sold for older cars from your favourite motor spares supplier will be quite suitable.
Eg Halford's Silicate antifreeze

If your tap water supply is hard or high in total dissolved solids it is advisable to dilute the concentrate with distilled or demineralised water or more simply buy it ready diluted.
There is guidance regarding tap water analysis in the VP owners manuals.

Generally conventional and OAT types of antifreeze should not be mixed because the inhibitors are not compatible with each other although there are some which claim to be compatible with all types.

The conventional silicate type is sometimes referred to as "inorganic acid technology" .... what Richard means by "IAT" in his post above

 

[lw395]

AIUI, IAT is not good with brass/copper.
The colours they dye coolant can be completely random.

 

[VicS]

AIUI, IAT is not good with brass/copper.
The colours they dye coolant can be completely random.

I thought it was OAT that was not good with brass or copper. Conventional antifreeze has been used with brass and copper radiators since long before any body thought to call it IAT

 

[sailaboutvic]

My MD 22 states " The coolant system is to be filled with a corrosionprotective anti-freeze mixture, 50% anti-freeze and 50% fresh water. Alternatively a mixture of fresh water with about 1 litre corrosion protective additive. (Volvo Penta accessory.)"
So it that green , red, blue, and black with white strips ?

 

[lw395]

I thought it was OAT that was not good with brass or copper. Conventional antifreeze has been used with brass and copper radiators since long before any body thought to call it IAT

Yes you are right, sorry!

 

[TiggerToo]

The difference is in the inhibitors.

For an MD2030 the traditional low silicate type of antifreeze such as V.P. Coolant ( green) is suitable.
There is no need to use a long life, organic acid technology (OAT) type such as V.P. Coolant VCS ( yellow) unless the engine manual specifically calls for it. It is specified for some of the more recent VP engines.

There is moreover no need to waste money on VP branded antifreeze. A conventional antifreeze sold for older cars from your favourite motor spares supplier will be quite suitable.
Eg Halford's Silicate antifreeze

If your tap water supply is hard or high in total dissolved solids it is advisable to dilute the concentrate with distilled or demineralised water or more simply buy it ready diluted.
There is guidance regarding tap water analysis in the VP owners manuals.

Generally conventional and OAT types of antifreeze should not be mixed because the inhibitors are not compatible with each other although there are some which claim to be compatible with all types.

The conventional silicate type is sometimes referred to as "inorganic acid technology" .... what Richard means by "IAT" in his post above

Thanks, ViCs for the comprehensive and clear answer. That really helps.

The only thing of note (following your comments) that Volvo branded A/F (green) turns out to be cheaper than Halfords' own brand... so I will try to get VP this time....

 

[RichardS]

My MD 22 states " The coolant system is to be filled with a corrosionprotective anti-freeze mixture, 50% anti-freeze and 50% fresh water. Alternatively a mixture of fresh water with about 1 litre corrosion protective additive. (Volvo Penta accessory.)"
So it that green , red, blue, and black with white strips ?

Hi Vic

I think the MD22 was designed and introduced in the 1980's so that was before Long Life/OAT coolant was invented and therefore the original recommendation from Volvo will definitely be for Standard / IAT coolant.

That doesn't necessarily mean that you can't use a modern OAT coolant as the formulation is different from those introduced originally but if you change your coolant every year or two anyway there's probably not much point in using the more expensive stuff.

Richard

 

[JumbleDuck]

I thought it was OAT that was not good with brass or copper.

Yes indeed - it can do very nasty things to cars which, like my older ones, have brass or copper radiators, thermostats and other cooling system parts.

 

[VicS]

My MD 22 states " The coolant system is to be filled with a corrosionprotective anti-freeze mixture, 50% anti-freeze and 50% fresh water. Alternatively a mixture of fresh water with about 1 litre corrosion protective additive. (Volvo Penta accessory.)"
So it that green , red, blue, and black with white strips ?

Hi Vic

I think the MD22 was designed and introduced in the 1980's so that was before Long Life/OAT coolant was invented and therefore the original recommendation from Volvo will definitely be for Standard / IAT coolant.

That doesn't necessarily mean that you can't use a modern OAT coolant as the formulation is different from those introduced originally but if you change your coolant every year or two anyway there's probably not much point in using the more expensive stuff.

Richard

I think the rule you can apply is that if the VP manual ( for an older engine) does not specify either green coolant or yellow VCS coolant you can assume the green one is the appropriate one to use. With more modern engines if the yellow VCS coolant or an OAT antifreeze is required the manual will say so.

At one time VP published a comprehensive guide to which engines the two types were suitable for. Unfortunately that info seems to have fallen by the wayside.

 

[sailaboutvic]

Thanks Richard and Vics , green is what I been using , mine is an 2001 engine .

 

[Heckler]

I thought it was OAT that was not good with brass or copper. Conventional antifreeze has been used with brass and copper radiators since long before any body thought to call it IAT

I was going to change the coolant on Tigger's VP MD2030. I see that there are two versions of coolant, one dyed green and one dyed yellow.

1) what is the difference?
2) what should I use?
3) why can't you mix them? (i.e. what happens if you do)
4) what volume of coolant are you likely to have to add if you have a standard sort of calorifier

Thanks in advance for information...

The "old type" AF in Portugal is blue, in Spain its green. The OAT stuff is yellow, dont ask how I know! I have just changed mine. I looked for the word glycol in the description on the bottles. My MD22 is ancient but does have an aluminium cylinder head and a cast iron block. It is important to chamge the stuff regularly on these donks, there is a spot on the "fire ring" area of one of the cylinders on the alloy head that can be susceptible to corrosion. I saw this on the Follow the Boat Youtube channel. One of our residents here, Devil Boy? He ended up with a new donk.
Stu

 

[VicS]

The "old type" AF in Portugal is blue, in Spain its green. The OAT stuff is yellow, dont ask how I know! I have just changed mine. I looked for the word glycol in the description on the bottles. My MD22 is ancient but does have an aluminium cylinder head and a cast iron block. It is important to chamge the stuff regularly on these donks, there is a spot on the "fire ring" area of one of the cylinders on the alloy head that can be susceptible to corrosion. I saw this on the Follow the Boat Youtube channel. One of our residents here, Devil Boy? He ended up with a new donk.
Stu

Its almost all glycol based

The common low silicate/ IAT and OAT antifreezes are based on ethylene glycol, aka ethane diol and commonly known as just "glycol"

Available, but not common in the UK as an engine coolant, is the low toxicity antifreeze based on propylene glycol, aka propane 1,2 diol.

Usually the old type, silicate/ IAT, antifreeze is blue or green and the advanced/ long life/ OAT type is yellow, red or orange, but not guaranteed.

 

[JumbleDuck]

Its almost all glycol based

Older car manuals used to have stern warnings against using methanol-based antifreeze, but I don't think I have ever seen the stuff. Not for engines, anyway - I think screenwash often has methanol in it.

 

[Heckler]

I thought it was OAT that was not good with brass or copper. Conventional antifreeze has been used with brass and copper radiators since long before any body thought to call it IAT

Its almost all glycol based

The common low silicate/ IAT and OAT antifreezes are based on ethylene glycol, aka ethane diol and commonly known as just "glycol"

Available, but not common in the UK as an engine coolant, is the low toxicity antifreeze based on propylene glycol, aka propane 1,2 diol.

Usually the old type, silicate/ IAT, antifreeze is blue or green and the advanced/ long life/ OAT type is yellow, red or orange, but not guaranteed.

I will photograph the Spanish language ingredients off the bottle next week and post it.
Stu

 

[Heckler]

Older car manuals used to have stern warnings against using methanol-based antifreeze, but I don't think I have ever seen the stuff. Not for engines, anyway - I think screenwash often has methanol in it.

http://www.malpasonline.co.uk/webresources/common/docs/6524.pdf
S

 

[VicS]

Older car manuals used to have stern warnings against using methanol-based antifreeze, but I don't think I have ever seen the stuff. Not for engines, anyway - I think screenwash often has methanol in it.

Back in the 1960s and 70s there was Holts Glycolmaster which was a blend of glycol and the cheaper methanol.

 

[RichardS]

Older car manuals used to have stern warnings against using methanol-based antifreeze, but I don't think I have ever seen the stuff. Not for engines, anyway - I think screenwash often has methanol in it.

I vaguely recall using methanol containing antifreeze in the 1960's but in those days the cooling systems were totally sealed unless there was a problem. I would assume that the methanol days were over once expansion systems became commonplace as the methanol would be the first component to evaporate off.

Richard