How to clean gunk out of cooling system.

[JustinC25]

Hey Guys,

I've just been charged with changing the coolant in my uncle's '01 Windstar. The problem is that the coolant resivoir has black (mixed) coolant, and much sludge. What would be the best way to clean it out without a flush machine ? and What coolant should I refill it with. I was thinking of using G-05, as I'm going to NAPA tomorrow to buy brakes for it.

Thanks,
Justin

I just realized that I posted this in the wrong forum. How to I move it to the right one ?

 

[JustinC25]

This is a repost, as I accidently posted it in the wrong forum.

Hey Guys,

I've just been charged with changing the coolant (along with other things) in my uncle's '01 Windstar. The problem is that the coolant resivoir has black (mixed) coolant, and much sludge. What would be the best way to clean it out without a flush machine ? and What coolant should I refill it with.
On mine I just drained the radiator, block, and hoses. But mine didn't have any sludge. It also has half the mileage.
What do you think of the chemical flush products by prestone, or Zerex ? For coolant, I was thinking of using G-05, as I'm going to NAPA tomorrow to buy brakes for it.

Thanks for your help,
Justin

 

[demarpaint]

You can add a cooling system flush, then do a heater hose T flush. Prestone sells a kit for doing the flush. As far as moving the post goes, hit "Notify" and tell the mods to move it to the Mechanical Maint section.

 

[HTSS_TR]

Remove the coolant reservoir from the car, use dishwasher detergent and hot water to clean the gunk/sludge then rinse with cold water real clean before re-install.

 

[Herz]

I used CLR in the old company 2000 astro van that was sludged and rusted to garbage. I put a entire bottle of CLR and topped it with distilled water and ran the van for a couple of long trips with it and drained it out real well with a hose and the engine running.

You should have seen the [censored] that came out of it.

NOTE: I dont know what CLR can do to gaskets so be advised it isnt a proven method!!! The van was on its last leg and the company really didnt care what I did to it and I had CLR on hand. It did run for another year of heavy towing and abuse before the transmission died.

 

[JustinC25]

That's a great idea. Never would have though of that.
What about the residual gunk in the cooling system ?
Do you recomend any of those chemical flush products ?

I know that this is a BIG system. When I did a complete (Rad, hoses, block) drain and fill on my '03 it took almost 3 gallons.

 

[mechanicx]

For cleaning sludge out here's what I would do. I think a radiator flush like Super Radiator flush works great and I'd get a couple bottles of that. There's two ways you could go about about flushing the system depending on how fast you want it to go and how hard it is to get to the engine drain plugs.

Since I'd probably change the thermostat and pressure cap, you could drain the radiator (and block drains if easily accessable). Then fill with water and the super flush, Run it till hot and the thermostat opens. Then drain the system again. Let it cool while you take take out the thermostat and reassaemble without T-sat. Then stick a water hose, preferably hooked to a hot water outlet like your washing machine hot water spickot, in to where the radiator hose hooks to the radiator and flush out the superflush with the engine running.

Another way that I think is easier, faster and probably more effective is to install a T-flush according to directions in the heater inlet hose. Flush all coolant out with the T-flush and drain radiator. Then add the super flush and run it hot. Now flush the super flush out using the T-flush hooked to preferably hot water to speed the process and clean better. Now, change the thermostat. You might want to drain the water out of the radiator so it will be easier to get half the capacity of new anti-freeze in and you should be good to go.

I think convential green or G0-05 would be a good choice.

 

[HTSS_TR]

Preston T-flush with Preston Super Radiator Flush are what I used to flush the coolant in my 240+k miles '94 LS400 every 4-5 years.

 

[fjasper]

Wood Bleach and Washing Soda. Coin of the realm. Search for 99-06-02-012D, it's a GM service procedure for fixing the sludgy/coagulated coolant problem. The flush they call for is no longer widely available, but powdered wood bleach (available at some Ace hardware stores, and probably other places) and washing soda (I found Arm & Hammer brand at an IGA store) are the ingredients they call for. Some people prefer citric acid (from the bulk/health food store at 1 pound per gallon-apparently a Mercedes-Benz recommended procedure), but I think oxalic acid (wood bleach) is particularly good for the coolant-mix problem.

Doesn't hurt to hit it once with dishwasher soap (not dish washing soap, you understand, but non-sudsy soap that goes in the dishwasher) first to take out any oils and let the acid flush work. Flush well between soap and acid. It's a long, messy procedure, but it does the trick. The real key is getting it hot enough during the flush, and rinsing completely, with engine running, between flushes. Getting a good rinse is almost impossible without hooking it up to a hose (hot water is definitely better), so the Flush 'n' Fill kit really helps.

I think you're better off driving it around than doing the high-idle procedure in the bulletin, but it's up to you. FWIW, mine kept belching horrible crud for 3 iterations of this procedure, but it had mineral scale worse than I'd ever seen. All better now.

Once it's totally cleaned out, you can pick a coolant without worrying about interactions. Don't be shocked if it starts leaking after you do a thorough flush. I'm not saying it will, just that sometimes the flush dissolves some crud that was plugging up a little leak. I found a couple of o-rings leaking after the procedure.

Also, be careful with the acid solution, it will mess with the finish on metal and plastics. I wouldn't let it dry on any parts you care about the looks of.

 

[GoalieFergy53]

I bought GM Heavy Duty Cooling System Cleaner (P/N: 88861344) to run in my bus's cooling system. I have no idea when the coolant was last changed by the previous owners, and I've heard this is the best stuff out there. I'm just waiting for a break in the weather to run it and see how it does.

 

[fjasper]

I guess I should mention that wood bleach (oxalic acid) and washing soda weren't picked at random, they're the components of the old GM heavy duty flush product mentioned in the service bulletin.

The old two-stage product (Prestone AS100=GM pn:123465000 or something like it) has been replaced with the new, one-stage product (pn:88861344). I haven't heard anyone with experience using both, so I can't compare the two. I'm sure either would work fine.

 

[Donald]

My guess is you have sludge in the reservoir but not in the rest of the system. I would take out the reservoir and clean it with Dawn or some dishwasher detergent, shake it a lot and use hot water. I would not use a radiator flush unless I saw sludge other places.

 

[Donald]

My guess is you have sludge in the reservoir but not in the rest of the system. I would take out the reservoir and clean it with Dawn or some dishwasher detergent, shake it a lot and use hot water. I would not use a radiator flush unless I saw sludge other places.

 

[Dan55]

I have used heavy duty two part cleaning systems in the late eighties that consisted of an acid and a nuetralizer. The vehicle was maintined properly yet there was a tremendous amount of aluminum scale. A few years later I started to see coolant in the oil and finally the engine seized (100K+). Could it have been the heavy duty cleaning system, a product from the 60's primarily designed for cast iron blocks and brass radiators. Maybe not,just a leakey head gasket instead. Since then I have steered clear of those type of products. If I had to I would use a light duty cleansers such as the Prestone products,due to the the predominant use of aluminum in coolant systems today

 

[mechanicx]

Originally Posted By: Dan55
I have used heavy duty two part cleaning systems in the late eighties that consisted of an acid and a nuetralizer. The vehicle was maintined properly yet there was a tremendous amount of aluminum scale. A few years later I started to see coolant in the oil and finally the engine seized (100K+). Could it have been the heavy duty cleaning system, a product from the 60's primarily designed for cast iron blocks and brass radiators. Maybe not,just a leakey head gasket instead. Since then I have steered clear of those type of products. If I had to I would use a light duty cleansers such as the Prestone products,due to the the predominant use of aluminum in coolant systems today


I do agree with you there. If I recall correcly the GM HD coolant cleaner was for badly sludged cooling system primnarily made of iron. The citric acid one like Prestone super radiator flush is probably best for most flushes. Also I assume the car in this post has original green. If you see it turn dark in the reservoir it probably turned acidic and that's from the acid causes hoses breaking down etc. It definitely needs flushed but a regularly radiator flush cleaner should do the trick.

 

[mongo161]

To clean out the radiator and cooling system I use Cascade Powered Electric Dish washing detergent. I've been using it for years when I need to get a thoroughly clean cooling system. I use this method every 2 or so years since I use the "Original Green Zerex" anti freeze/ coolant. October or November is a good time of the year to do this since the weather is nice in my neck of the woods.....not hot and not cold but seasonal temps.

First, I drain out the radiator and refill with it with distilled water. I then drive the truck for 100 miles or so with the heater on most of the time, Full Blast, then let the engine cool thoroughly...usually overnight. The next morning, I remove the radiator cap and unfasten the bottom radiator hose from the engine block and let the radiator drain, via the hose, into a large container. I reattach the radiator hose when it has completely drained.

Next, I take a 3 cups of Cascade powered dishwasher detergent and dilute this in distilled water. I pour the mixture into the radiator and fill it until it is full....start the engine with the cap off the radiator and continue filling the radiator as the air leave the system. I then drain this mixture the next morning....again via the lower radiator hose, and you would be amazed at the sludge and crud that comes out. The last rinse is a fill of distilled water and run it for a day to rinse the system.

The final day.....I fill the radiator and system with the predetermined amount of Antifreeze/Coolant and distilled water. This method is very handy for those people who do not have access to a hose and need to rinse their system.

I've never had a problem using the Powered Electric Dish washing Detergent since it does not foam or bubble up. I still have my original radiator and it runs clean. I learned this trick from a mechanic who replaces head gaskets on vehicles. He has his customers use this approach to get the pieces of old gasket and sealer out of the engine block and radiator.

 

[calvin1]

I've heard the electric dish detergents are big with the diesel guys when they need to clean out a cooling system after the oil<>coolant heat exchanger lets go. That powder is a really aggressive cleaner, won't foam and rinses out fairly easily. Also, you radiator won't have any water spots for when company comes.

 

[mongo161]

It has been great stuff to use. I make sure that I heat up some distilled water first to dilute the powder. After all the old AF has been removed from the radiator and the cooling system with distilled water, then add in the mixture of diluted detergent with lots of distilled water. Take the vehicle for a nice ride....let the engine cool overnight....then drain the radiator and the system. Another flush with plain distilled water can be done....but I've found that it's not necessary. The radiator, heater core and the system has been purged of all the old AF, rust or sludge.

 

[sciphi]

I'll give that a try in the spring with my mom's overheating Subaru. The Prestone flush just flushed my wallet.

 

[Virtuoso]

Saturn also recomended the use of Cascade detergent when flushing the cooling systems of SL1's that cracked the head.