Cooling System Maintenance ?
 

Just curious how many of you have done some sort of cooling system maintenance on 2002 or older Boxsters? More specifically coolant flushing and hose replacement front to rear?

My 2000 has approximately 73,000 miles and I've done nothing except install the updated coolant tank cap. I'm not sure what if anything the PO did.

I've read about the occasional coolant tank replacement due to cracks and radiator cleaning, but don't often hear about replacing the hoses and coolant.

Just curious and wondering if I should be servicing these items with the age and miles on my car?

Thanks,

ddb

Except for the cap, all stock on my 01 with about 60k.

Hi,

Porsche claims their coolant is Lifetime, but don't believe it. It is simply a silicate and phosphate free Glycol based coolant. This s/b changed every 5 years/150k mi. (whichever comes 1st) in order to provide maximum corrosion protection. It is the organic carboxylates which breakdown after this interval.

Instead of buying the super-expensive Porsche Coolant, Zerex Extreme Life 5/150, Texaco Extended Life, Shell Rotella® ELC Extended Life Coolant, UNI-GARD
5/150, Mercury Extended Life Coolant Anti-Freeze, all meet or exceed Porsche Coolant requirements and are much cheaper. Use of any other type coolant is not compatible with the system and can form a gel-like substance if mixed with the proper coolant which can then obstruct flow, create hotspots, etc. Hope this helps...

Happy Motoring!... Jim'99

true?
 

MN,
The other day I came across a "universal" coolant which claims to be compatible with everything out there.

If the claim is true, it would be a good thing for me who has to deal with everything from a 1973 to a 2002.

Your take on this?

Jim I have been thinking of flushing my coolant system even if I don't change out the oil cooler,just cause it has been in the car it's whole life. Now that whole process of running the car at 2,500 RPM for 10 minutes with the revs up to 5k and then running it at 2,500 RPMS for another 10 with revs to 5k again every 30 seconds,is that needed?

Hi,

It may well be compatible, but that's no recommendation to mix it with other types. There are basically two types of Coolant out there (there are more, but the differences aren't really relevant for this discussion). Both are usually Glycol based (either Propylene Glycol, or Ethylene Glycol).

In addition to the base fluid, there are a small amount of other ingredients including corrosion inhibitors, antifoaming agents, dyes and other additives. While these other ingredients make up only a small fraction of the overall coolant, they are what differentiate one coolant from another.

Conventional Coolants typically use a Phosphate/ Silicate mix as the main components in their Inhibitor pkg. Conventional inhibitors like Silicates and Phosphates work by forming a protective layer that actually insulates the metals in the engine and Radiator from the Coolant. These inhibitors can be characterized chemically as Inorganic Oxides (silicates, phosphates, borates, etc.). Because these Inhibitor Pkgs. are depleted by forming this protective layer, conventional Coolants need to be changed at regular intervals, usually every two years.

But, in Europe, with unusually hard water (compared to the US), minerals forced Coolants to be Phosphate-free. Calcium and Magnesium, minerals found in hard water, will react with Phosphate Inhibitors to form Calcium or Magnesium Phosphate, this can cause the formation of scale on hot engine surfaces. This results in a loss of heat transfer and/or corrosion under the layer of scale.

Instead of Phosphates, conventional European coolants contain a mix of Inorganic Oxides like Silicates and Inhibitors called Carboxylates. Carboxylates differ in their corrosion protection in that they chemically interact with the metal at corrosion sites in the engine, instead of forming a layer of Inhibitors that cover the total surface.

In Asia, where the water is OK, Silicates are the problem. Issues with water pump seals, heat transfer, toxicity and non-biodegradability led to a ban of coolants containing Silicate. To provide protection, most coolants contain a mix of Carboxylates and Inorganic Inhibitors like Phosphates.

Extended-Life Coolants are usually Carboxylate-based and were developed to be globally acceptable and provide superior performance over existing chemistry. This chemistry is also known as Organic Additive Technology (OATs). Because full Carboxylate coolants have no Silicates, they meet the stringent requirements of the Asian specifications, but they also meet the European coolant requirements because they have no phosphates. These coolants have developed international popularity due to having an unsurpassed corrosion protection for extended time intervals. They have the added benefit of working better, being non-toxic and are biodegradable.

In these Coolants (which is what Porsche uses) the corrosion protection is provided by Carboxylates. Carboxylate Inhibitors provide corrosion protection by chemically interacting with the metal surfaces where needed, not by laying down insulating layers. This allows: extended life cycles, unsurpassed high temperature aluminum protection, as well as heat transfer advantages on both hot engine surfaces and radiator tubes where heat transfer is critical. But, it can still breakdown in usually a 5yr./150k mi. interval. Porsche calls it Lifetime for Marketing purposes. They expect the average car will have it's cooling system opened or drained for Service sometime in it's Coolant's 5-year life span and have it's Coolant replaced then. Hope this helps...

Happy Motoring!... Jim'99

when i had my cap problem, i flushed mine w the yellow bottle Prestone, said for all cars and all models.
and it was like 274359832758374 times cheaper than porsche coolant.
no problems with it

Hi,

Yes, these run-in procedures are very important to insure that all air is purged from the system. You don't want an air bubble in say the head creating a hotspot and possibly burning a valve, cracking a piston, the head, and such...

Happy Motoring!... Jim'99

Hi,

That was probably not the best thing. The coolant you describe contains silicates and these can form a gel reducing/blocking Coolant Flow, this problem has come up on several Boxsters.

In addition, this type of Coolant insulates the metal of the engine (read below) and causes a reduced heat transfer (not a good thing on an alloy engine). If it were me, I'd drain it and flush it ASAP and use the proper Extended-Life Coolant...

Happy Motoring!... Jim'99

Jim, where can i purschase those other coolants you mentioned above?
a local napa/pepboys/autozone?

The Texaco extended life coolant is available at Kragen.

i dont know of a Kragen around chicago area....

damn just notied this is my 900th post :cheers:

Dj, you should be able to find this stuff at any of the many auto parts chain centers in the Chicago area like Murray's Discount Auto.

ok thx, ill look into it.

Nice to hear from someone who (appears to) know..
 

... what they are talking about. I suspected it was not permanent, btu not being a chem-e, I wasn;t really sure.

I have always serviced coolent ~5-7 years "need it or not"

Of course, I've always had timing belts and water pumpts to do at that time anyway .....

Grant

Which leads me to a question- I always hear that you should always use distilled water whenever mixing with coolant, but wonder- Do dealers really carry a huge tank of distilled water back in the service area when they do coolant flushes? I personally doubt it, and would think that they'd be using plain tap water. Anyone know for sure?

Dealer's Probably Don't, But
 

that doesn't mean you shouldn't. The dealer's agenda is different than yours. Any problems developing with your car next year is very good for the dealer, but not so good for you. Distilled water will ensure no added mineral deposits, prolonging the life of your cooling system.

I have a related question;

What is the "Normal" level of coolant when the engine is cold?
(as looking at the level indicator on the reservoir)

When cold my level indicator shows just over the minimum, when hot is is at the Max level.

On my SUV the coolant reservoir shows the same level wheather cold of hot.

-T

Hi,

The Manual states that the Coolant level s/b checked when it is COLD and that the fill mark should lie between the MIN and MAX indexes. Hope this helps...

Happy Motoring!... Jim'99

well if you leave a bottle of regular water sit for 24hrs its the same thing as distilled water, or something like that