dex sludge

[its840]

ok im trying to figure out the best way to remove dex sludge.. from what i have found gm use to offer some power stuff that you would put in there that would break down the sludge allowing you to flush it out.

GM P/N 12346500
which is the same thing as
Prestone P/N AS100 Heavy Duty Cooling System Cleaner

further reading i have found that it is oxalic acid (or wood bleach) and use dish soap to neutralize it.

cheaper alternative commonly found at most hardware stores.. im just wondering if anyone have any exp with either of these...

pretty much just following gm (#99-06-02-012D) service info.
GM Service Information

[imidazol97]

ok im trying to figure out the best way to remove dex sludge.. from what i have found gm use to offer some power stuff that you would put in there that would break down the sludge allowing you to flush it out.

GM P/N 12346500
which is the same thing as
Prestone P/N AS100 Heavy Duty Cooling System Cleaner

further reading i have found that it is oxalic acid (or wood bleach) and use dish soap to neutralize it.

cheaper alternative commonly found at most hardware stores.. im just wondering if anyone have any exp with either of these...

pretty much just following gm (#99-06-02-012D) service info.
GM Service Information

For all the trouble of installing the T and getting a power flusher to use, I'd take it to a qualified, good garage who is actually already practices at doing this and pay them the $100 or so which includes refill with good coolant, which includes DexCool. Then just change the coolant every two years like should have been done.

Also, I'm questioning the dish soap as the neutralizer. The instructions from GM point out the neutralizer is corrosive to aluminum. That means it is a base chemical, of the family of NaOH or similar. The oxalic acid in their mixture probably includes some buffers. Same for the neutralizer including chemistry to try to control its damage to the aluminum. Dawn dish detergent ain't gonna do it.

[2002BonnevilleSE]

When I got rid of the death cool in my 97 I just used the right rad.flush as directed from Advance Auto and kept runnning water through it with the car running. Once clean water came I drained it all out and installed a new 180 thermostat and reg.coolant.
No problems after doing that. Never over heated.
Still need to do it for the 02.

[its840]

so after the flush.. should i go back with dexcool?? or the green stuff?

ive hose flushed the cooling system out. and currently running PEAK cooling system flush in it now. has been idling outside for about an hr now and temp sits about 180*... perfecto!!! hopefully it stays there..

but what should i put in after??? any thoughts?

[Ken_W]

From what I've read, I suspect many here will tell you to avoid Dexcool like the plague.

Others will mention that the stuff was reformulated around 2003-2004 after the problem was recognized, and that the Dexcool sold today is not so bad. They will also point out that you are supposed to change this coolant every two years or so, and that you should not have any acidity problems if you do so.

Still others recognize both sides of the debate, and use Peak or Prestone "mixes with any" coolant just to be on the safe side. This seems to be the main consensus on the board, especially if you still have the original LIM and UIM gaskets in your engine.

I've noticed that most shops and dealerships still use Dexcool, as it (the reformulated version) remains the official manufacturer-recommended coolant. You just have to be diligent about changing the fluid every two years.

So; not a direct answer for you here, but hopefully enough info to help you reach your own conclusions.

Ken_W

[its840]

ok so took the tstat out and flushed it with the cleaner stuff. it sat there idleing for like 3 hrs and stayed like right around 200* then i flushed agian with water to make sure all the cleaner stuff was out of it.

then i replaced the tstat (3 days old) and refilled with coolant. within an hr its almost to the red zone.. so i shut it off.
this is starting to get frustrating. after i shut it off i turned it back to the on position and i didnt hear a fan kick on...
so idk if its the fan thats not kicking on or does it only kick on when the car is running.. dont see how that would matter but..

[its840]

ok well i think i have determained that the radiator fan is not working right. with temp about 275* turned the car on and the fan would spin then stop and then spin really slowely.. so i made it to advance just in time to pick one up..

[willwren]

www.dex-cool.net for all our suggestions and some risks.

[Ken_W]

Does a regular flush get Dexcool sludge out? I have a couple bottles of Prestone Super Flush I planned on using tomorrow, but (since I have noticible sludge in my overflow bottle) should I take it to a power-flush shop instead?

(Note: bought car in June, don't know what it was last serviced, but no obvious cooling problems.)

What do y'all think?

Ken_W

[bill buttermore]

Does a regular flush get Dexcool sludge out? I have a couple bottles of Prestone Super Flush I planned on using tomorrow, but (since I have noticible sludge in my overflow bottle) should I take it to a power-flush shop instead?

(Note: bought car in June, don't know what it was last serviced, but no obvious cooling problems.)

What do y'all think?

Ken_W

If it were my car, I would isolate and reverse flush each component (engine, radiator, heater core) separately until I saw clean water coming out and no restrictions in flow. Here's is how to do this: Reverse Flush Cooling System

The method described on the Prestone flushing Tee kit is not as thorough as separate component reverse flushing.

[Ken_W]

I did the separate-component flush procedure today, with the exception of the heater core (because one of the heater hoses was glued to its engine port and I gave up trying to get it off after an hour). I saw very little debris or sludge come out. I ran my finger around the inside of the rad hoses, and these seemed fairly clean also. So; I guess it was mainly just my overflow bottle that had sludge in it (or the flush failed to get it out of the other areas).

When it was time to clean the overflow bottle I had a heck of a time trying to find tools to push a washcloth around in there. In frustration I tried something that worked really well, and I post it here for those who may find themselves in a similar situation:

I took the bottle into the house and let it soak in the kitchen sink for 45 min in hot water and Dawn dish soap. Then I came back and vigorously shook the whole thing (covering the holes, of course). I then got a washcloth and put it inside the bottle. I was able to wipe down a small area with my fingers, but there were many areas beyond reach. I got a spatula handle and was able to wipe down more areas, but there were still many nooks and crannies that were impossible to reach.

Then I came across something simple that worked. I let most of the water out and shook the whole thing with the washcloth inside. I noticed that the bashing of the wet washcloth against the areas with sludge succeeded in removing the sludge -- it was easy stuff to wipe off if you could reach it. I then shook the thing from side to side after making sure the washcloth was in sludge-covered areas. The sliding of the washcloth back and forth removed more sludge. After repositioning the bottle numerous times, I was able to get it pretty clean in this manner.

I then rinsed it several times to get the Dawn soap out and let it air dry before putting it back into the car.

I don't know if the soaking in Dawn made any difference, but the washcloth inside the bottle certainly did. My kitchen sink sprayer was broken, but that might work too if you have one.

Ken_W

[sonoma_zr2]

bb's in the soap solution will also work wonders.

[00Beast]

Or marbles or small pebbles.

[imidazol97]

I used a coat hanger bent to let me push the small piece of an old towel around to rub the right spots clean.

Dawn is an excellent oil and grease remover.

[The_Maniac]

I love these ideas on cleaning the bottle!

Earlier this year I drained the Dex on my '04 Monte Carlo (only car in the fleet running Dex). I did not run any flush solution in it. I did repeatedly fill the radiator with water, run the car a couple minutes, re-drain the system. I then took the bottle off my car and was lucky that just filling it halfway, plugging the holes and shaking vigoursly cleaned mine out.

These ideas everyone posted (wash cloth, BBs, marbles and such) are so incredibly simply, I am stunned I didn't think of that myself!! I love it!! Thanks guys, I am sure even with regular maintenance, I will re-visit cleaning the water bottle again!

[harofreak00]

It should also be noted that if you don't want to spend the time to clean it, you can purchase a new overflow tank for like $12