Coolant Madness. Which kind?

[blakersE30]

hi all,

i rec'd my new, larger fuel injectors from PP (yay!), and note that I'll be draining coolant to get them replaced ....

soooooo, might as well do a radiator flush/refill.

question is .... what kind of coolant to use?

i presume my radiator is ALUMINUM inside that plastic shell (can someone verify?), and that PHOSPHATES are *bad* re: corrosion.

after digging around on the web, there all all sorts of discussions abt pH ("use MBUSA's cuz it's ph=7-7,5 rather than 8-8.6"), additives, etc.

questions:

(1) is the BMW coolant ($13-22/gallon!) necessary recommended?

(2) is a 3rd party (Zerex, Prestone, etc.) phosphate-free, extended life a better choice?

(3) what abt these DEX-COOL/G-05 "new" coolants, that are ethylene glycol + organic acid compositions? they seem to be recommended (sometimes REQUIRED) for newer models, but what abt the trusty ol' E30?

(4) is deionized/distilled/tap water an issue?

(5) since I've always had flush/refill done at a "Jiffy Lube", what've they been typically putting in?

(6) does ANY of this really matter ...

thx,

richard

[golden]

I think ths matters down the road as passages get blocked due to build up around 180-240k with the lesser manny moe and jack brands of AF. I'm going through this now with my 8o's 5 series as nothing seems to keep it under 7/8ths to red.

[wludavid]

I used BMW coolant and distilled water from the grocery store. I tried to flush it out the best I could with tap water. It seems to keep the overall coolant temperature low enough, though I'm a little concerned with hotspots. I think I'm going to put in a bottle of Water Wetter next time I have the occasion to drain the radiator.

It's probably worthwhile to use the expensive BMW stuff. You cut it with water, so it's not too bad, and you can reuse it - it's not like engine oil or brake fluid.

Its very hard to drain all the coolant from the system. The Bentley says to remove the radiator plug and engine coolant plug, but the engine plug is a b!tch to get to and you can't get it all out anyway. I've read that a couple sucks from a shop vac will get out what can't be drained from the radiator, but I haven't tried it myself.

[Jared at Pelican Parts]

I just flush the system really well with some radiator flush and run a 50/50 coolant mix. Typically just Prestone. Last time I flushed it, it came out looking the same way I put it in, with no problems. Car never gets over 1/4 on the gauge.

[kraut-runner]

I copied this from Pestones website. Makes sense to me. Plus I don't have a BMW dealer too close. So i'm going with the longlife Prestone and distilled O2



Q. Does Prestone® Antifreeze/Coolant contain phosphates?
A. Some European automobile manufacturers request that a phosphate-free antifreeze be used in their vehicles. This issue is related to the extremely high mineral content of the water in Europe. If you were to mix an antifreeze that contained phosphates with the type of water they have in Europe, it may produce deposits that can settle in the cooling system and promote corrosion. However, in North America we do not have this type of water problem. Typical North American coolants have contained phosphates (which is part of the corrosion inhibitor package) for many years. Therefore, the question of phosphates is a non-issue here in North America. Prestone® Antifreeze/Coolant is completely safe for use in both foreign and domestic vehicles. For those consumers who would feel more comfortable using a phosphate-free antifreeze, our Prestone® Extended Life 5/150 Antifreeze/Coolant is phosphate, silicate, and borate free. This coolant uses a special chemistry and technology that extends the life of the corrosion inhibitor package so that it lasts for five years or 150,000 miles (whichever comes first), and is safe for all cars and light trucks (old or new). Prestone® Extended Life 5/150 Antifreeze/Coolant has been approved by General Motors under their DEX-COOL® specifications and is compatible with other DEX-COOL® approved coolants.

* DEX-COOL® is a registered trademark of General Motors Corporation.

A;) ;) ;)

[jamin325i]

has a nice chart telling which of their 3 coolants is recomm. for makers and model year.
the yellow-looks clear- is recomm. for all bmw model years-not the orange, not the green.

[Wayne 962]

Wow, good info - didn't know that...

-Wayne

[Bear]

I use ZEREX G4 in my 1988 750 as it is formulated for many European cars. So far the V-12 justs sings along and no coolant issues. Purchase at Auto Zone or PEP BOYS and it will not cost a lot of money.

[Wayne 962]

I've been using the BMW coolant in my 5-Series. However, I just saw that Prestone now makes pre-mixed coolant for lazy people like myself, so I've been using that in my cars ever since (used it in the Ferrari - works pretty good). With the premix, you don't have to worry about things like hard water, etc...

-Wayne