was this just a random thought you came up with???
Pat wrote:I also read the topic about Dex-Cool do we need a specific cap for this.
Pat wrote:I also read the topic about Dex-Cool do we need a specific cap for this.
MACS 2001: GM and Texaco “Bare All” about DEX-COOL®
by I.M. Cool
Appeared Jan/Feb 2001 Cool Profit$ Magazine
© 2001 All Rights Reserved
As in the past, the MACS 2001 Convention and Trade Show in Orlando provided some very interesting and helpful air conditioning information. However, the sleeper presentation at this show was not about refrigerant, but—of all things—engine coolant! (Sleeper does not refer to making you sleepy; it was anything but boring.)
Marketing departments of major consumer goods manufacturers are known for their attempt to conceal even a shred of negative publicity about their products. You can’t blame them; you do the same in your business. That’s why it was refreshing to witness a candid GM/Texaco presentation about DEX-COOL coolant and its related field service problems. I give the big guys credit for even bringing up the subject because, well, let’s face it, there are not a lot of kind words being spoken about this coolant at automotive service shops today. (Especially at radiator shops.)
GM Cooling System Contamination Video @ $10 +S&H - Call 800-393-4831Left: 14-Minute GM Training Video is now available to help technicians service known cooling system contamination problems in specific GM vehicles.
GM’s Jay Dankovich and Equilon Enterprises’ (Texaco) Stede Granger directed a 2-year study of thousands of DEX-COOL cooled vehicles. Armed with the results, they really didn’t have anything bad to say about the coolant. In fact, they strongly defended the product’s reputation. What they revealed to the audience is that specific models of GM vehicles have specific cooling system contamination problems. And essentially, that DEX-COOL is not the culprit!
Their presentation started with a 14-minute video that is now being circulated to technicians at GM dealers nationwide. In the video, GM’s trainers succinctly described the problems that have been found and the corresponding corrective actions to be taken by technicians.
Suggestion. This video is a “must see” for all technicians considering themselves antifreeze/coolant experts. Without this information, your cooling system service knowledge of late model GM vehicles is severely limited. Seriously!
Fortunately, you can buy the video for only $10 (plus S&H). Call MSX International of Auburn Hills, Michigan at 800-393-4831. Ask for the DEX-COOL Video: “Understanding Radiator Cap and Cooling System Contamination.” Part number: RADCAPK. Immediately following this article is a report on this training video by John Brunner, recently retired GM field service representative.
What was said at the presentation? Besides the video, Jay and Stede included their personal observations about the study. At the end, they fielded several questions from the audience. Here’s a recap of their entire presentation.
1. Keep the cooling system filled. In fact, fill the reservoir bottle to “Hot” level when the system is cold. Problems arise when a system’s coolant level is not maintained. (Fleet vehicles receiving regular maintenance, and with reservoirs kept slightly above normal, do not show signs of contamination. This even applies to the specific “problem” vehicles.)
2. The coolant problems found in this survey were caused by system contamination, and not due to the breakdown of DEX-COOL.
3. Check and keep the pressure cap clean and functioning. A contaminated and/or malfunctioning cap causes low coolant levels, which in turn causes overheating and a greater loss of coolant: the notorious vicious cycle. No matter what the vehicle, if the cooling system acts suspiciously, test the pressure cap.
4. On the ST vehicle models mentioned in the GM DEX-COOL video, you “must” replace all suspect radiator caps, especially those with a Drop-Center design, with a Stant Model 10230 or 11230 (Spring-Center type). (Just do it.)
5. Make sure that the coolant is at a 50-50 mix. Often, the flush water was not being removed from the engine block. Consequently, when a 50-50 mix is added to the system the resultant mixture could approach 30-70. Like any fluid that has been diluted beyond its recommended levels, the lowered level of inhibitors will not be able to protect the coolant system effectively. Low levels of inhibitors can cause pitting on aluminum surfaces and general corrosion of cooling system metals.
Cutaway of Drop-Center CapLeft: Drop-center, “vented” radiator pressure cap. GM found this cap (like the Stant 10231) to be less helpful than a Spring-center cap (shown below) in controlling the formation of contaminants in the cooling system. If contamination forms, the debris fouls the valve and restricts its ability to seal. In turn, the coolant boils at a lower temperature. Coolant loss is accelerated and so is the accumulation of contaminants.
Cutaway of Spring-Center CapLeft: Spring-center, sealed radiator pressure cap (like the Stant 10230). This is the preferred cap for GM applications that are more prone to accumulating cooling system contaminants.
6. A safe method of achieving a true 50-50 mix is to first determine the actual capacity of the system (use the owner’s manual). Then add 50% of “that” amount of undiluted DEX-COOL (or any coolant), and top it off with water.
7. Mixing a “green” coolant with DEX-COOL reduces the batch’s change interval to 2 years or 30,000 miles, but will otherwise cause no damage to the engine. In order to change back to DEX-COOL however, the cooling system must first be thoroughly drained and flushed.
8. Bacteria cannot live in a hot, Ethylene Glycol environment and is therefore not a threat to DEX-COOL.
9. While there have been intake gasket failures on CK Series, V8 powered vehicles for various reasons, DEX-COOL has never been found as a cause.
10. Use a refractometer to check the condition of DEX-COOL. Its inhibitor package is strong enough that if the batch still provides proper freeze protection, it is probably still providing proper corrosion protection as well.
11. DEX-COOL can handle the minerals in hard water better than silicated conventional chemistry coolants. Drinkable water is suitable for top off.
12. In ST Blazer applications where the radiator cap is mounted at an angle to the ground, the vehicle is more susceptible to radiator cap contamination and its related problems. The Stant 10230 is a wise choice for these vehicles.
Does it still use the fiber gasket, or rubber?rmzl wrote:Just changed my cap last week. Got the GM one (# RC92 ??). ...
CrazyChaz wrote:I also picked up the Stant 11230 16lb cap at Advance Auto Parts. Its seems to fit just fine for me, plus im not to worried the package also says it fits 10230 applications.
HenryJ wrote:I would say again that I have seen 20 yr old green coolant that never posed a problem even when subjected to air , and creek water.
Yet I have seen numerous cases of sludged , corroded, damaged parts , etc. in systems using Dex with very little neglect.
Glad I went green, and I'll never go back.
The extended life coolant was a good idea, but just didn't pan out in my book.
2bunik wrote:when you switch ... all you do is remove the orange stuff and replace it with the green ?????
Do you still have time for these pictures? I really need to do this mod, but I see people here are using different caps from different mfg's, and I'm a little unsure about which one to choose.f9k9 wrote:If you want side by side shots of underside and top of caps, I will be glad to post them.
killian96ss wrote:Do you still have time for these pictures? I really need to do this mod, but I see people here are using different caps from different mfg's, and I'm a little unsure about which one to choose.f9k9 wrote:If you want side by side shots of underside and top of caps, I will be glad to post them.
HenryJ is using Napa cap part # 703-2462
Jim is using Napa cap part # 703-1446
CrazyChaz is using Stant cap part # 11230
rmzl is using GM cap part # RC92
Retep is using Stant cap part # 10230
f9k9 is using Napa cap part #703-2462 & was using O'Rileys cap part # ?
I know I need a 16 lb cap with a rubber gasket that covers the radiator opening better than stock, but which one is the best choice?
that orangy powder is dehydrated dexcool. And, if fluid can leak out, air can leak in. Air + Dex = BADrmzl wrote:Hi everybody,
Updating on my cap from last summer. The fiber upper gasket gave way, it was leaking very slightly and an orangy powder was forming around the edges. I found a rubber gasket in my toolbox which was quite thick and replaced it. I'm not sure how it will hold. I kinda like the stock look with Dexcool sign an so on, so I'm waiting to see before getting one of those all metal ones.
barch97 wrote: Air + Dex = BAD
I am not the original owner, but when I bought my CC it only had 6k miles, and I doubt the cap was changed as everything else was completely stock. I will take the cap to my friends house today and get some pics with his digital. The cap is made of black plastic and has orange writing on it.barch97 wrote:Are you sure that was the "OEM" cap? are you the original owner? maybe someone beet you to it?
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