cheap cooling tip

[GeorgeZ]

While makers of glycol suggest a 50/50 mix be used for year round simplicity, I have found that a 30 or 35% mixture performs in my car much better in the summer months. A 30% mixture is signifigantly less viscous than a 50% mixture. Given the nature of the water pump, the amount of liquid being pumped is signifigantly more. My car ran 12° cooler last summer under identical conditions after making the change.

[rtheriaque]

The reasoning is simple- water is a far better heat transfer agent than "coolant." This is why race cars with short-life engines run straight water. However, by throttling back your mixture you aren't getting the anti-corrosive benefits of a 50/50 mix. Everything in life is a compromise- straight coolant wouldn't allow any internal corrosion, but it wouldn't cool very effectively, either.

I'd stick to the 50/50 mix, personally.

[pkbinplano]

Water Wetter

[Kidasters]

Less viscous? At what temp? At room temp, ok - maybe. At 190 F? Bet there's not much difference....

+1 on the corrosion resistance.

PS - Racer's don't run water because they want to. Racers run water in case they have a leak, and they don't spray slick glycol all over the place and cause a wreck.

[02Les]

Exactly.

That's what BMW recommended in the 1602/2002 Glovebox Handbook all those years ago.

[02for2]

Racer's don't run water because they want to. Racers run water in case they have a leak, and they don't spray slick glycol all over the place and cause a wreck.

+1!

Glycol is illegal in most racing categories. On a Track, it's like Instant Banana Peel!

Cheers!

[c.d.iesel]

THE 'OFFICIAL" word :

1.0 General Information On Long-Term Antifreeze And Corrosion Inhibitors

The cooling system of BMW cars must only be filled with reputable brand name ethylene glycol long-term antifreeze

having corrosion inhibitors that are compatible with aluminum radiators.

Coolants must fulfill four basic requirements.

— Guarantee sufficient cooling.

— Protect various metals (gray cast iron, steel, aluminum alloys, brass, copper and solder) against corrosion.

— Prevent excessive silicate gel precipitation, which may cause clogging of the cooling system.

— Guarantee operation of cooling system in winter (prevent freezing of coolant) and in summer by boosting the boiling

point.

The quality or grade of a long-term antifreeze and corrosion inhibitor is very important to be able to protect metal (gray

cast iron, steel, aluminum alloys, brass, copper and solder) in the cooling system against corrosion. It guarantees full

operation of the cooling system in winter and also increases the boiling point at high outside temperatures and under

heavy loads.

Initial Filling in Factory

The factory fills the cooling system for protection against freezing, for the U.S. and Canada, down to -34°F (-37°C).

This means an antifreeze ratio of 50% antifreeze and 50% water. In severely cold areas, the antifreeze can be increased

to 60% which provides freezing protection down to -62°F (-52°C). Do not exceed a 60% ratio of antifreeze.

The specified antifreeze ratio is important, since an insufficient amount would impair antifreezing and corrosion inhibiting

protection. An excessive amount would not improve freezing protection, but instead reduce freezing protection.

Change Intervals

Regular checking of coolant concentration is part of Inspection I or II. Refer to applicable Model Year Service

Maintenance Checklist for change intervals.

Long-Term Coolant

The BMW engine coolant has a long-term rating, except when the cooling system requires repairs. This coolant does not

require a service interval if no repairs are made to the vehicles cooling system. Drained coolant is not to be re-used. Top

up with new coolant.

Remarks and Limitations

Only tap water of drinking quality with the following properties may be used as coolant.

Appearance — colorless, clear

Residue — without suspended matter

pH value — 6.5 - 8.0

Total hardness — max. 357 PPM Calcium Carbonate

Chloride content — max. 100 mg/l

Sulfate content — max. 100 mg/l

Page 2 of 2

The antifreeze concentration in a cooling system should be checked before the beginning of winter. When determining the

mixture concentration it is important to make sure that there is sufficient protection against freezing.

A hydrometer (radiator antifreeze tester) is required for correct determination of antifreeze concentration. The composition

of long-term antifreezes and corrosion inhibitors differs between manufacturers.

BMW Anti-Freeze/Coolant contains no nitrites or phosphates and has been formulated to prevent excessive silicate dropout.

Order the 1gallon container under BMW Part No. 82 14 1 467 704.

Note: Do not mix BMW Anti-Freeze/Coolant with different antifreezes which contain nitrites and/or phosphates and a high

silicate formulation.