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Rydlyme cooling system flush

boncrshr

NAXJA Forum User
Location
Texas
My buddy and I decided to do a cooling system flush on our 2000 XJ's, 215K and 15OK mileage. I had been reading about Rydlyme for outboards and thought it might work good on our Jeeps. So we rigged up a marine transfer pump to pump into the water pump outlet and ran a hose from the exit of the heater core into an oil pan we used as a sump.

We ran the solution at 50% for three hours and had pretty dramatic results...large amounts of fine rust down the driveway, plus larger sediment in the sump pan. We were surprised how well it circulated throughout the whole system, lots of pressure on all the hoses and out the radiator cap.

I can tell my temp is more stable and the Jeep runs noticeably cooler on the highway. However; my buddy has a ScanGauge...on the trip to my house, he was running 206-210 on the highway at 70mph. On the trip home, he was running 193-196 at 70mph....pretty cool we thought.

Anyways, here's some pics of the pump set up, the catch pan, and my driveway after the flushes.

http://community.webshots.com/album/582419215hGYwht

And a link to Rydlyme...btw, it is 24 bucks per gallon, and we each used a gallon.

http://www.rydlymemarine.com/
 
Now that is some interesting stuff. I have bookmarked the site for this Spring as the Heep is due another chem clean. I chem clean every other year with coolant change in the 'tween years.

Taking the pre and post measurements are a nice touch. 14 degree post clean temperature drop just shows the negative effects of corrosion on the system.
 
$24/gallon is way overpriced.
 
$24/gallon is way overpriced.

For Rydlyme or a system flush? There was only one dealer close to me, and his price was about the same as online.

One kinda cool thing about flushing the system this way is that you are not using your engine to circulate the coolant, which saves you some gas money...
 
$24 may sound expensive but, two years ago when I grabbed my current XJ it took 4 shots at the thing using the "over the counter drive it around for at least 10 hours" stuff. It wan'st until after the 4th flushing that "coolant" dropped out clean. So, factor in the cost of the chemicals and the fuel. I would have gladly popped the bucks just to be done in the 3 hours or so it would require.

The drop from the first flush came out jet black. And chunky. Ultimately, I had to replace the radiator. After taking the it apart and letting it dry, I found dirt in the core. I just can not imagine what the PO used for water. Even unfiltered well water is cleaner than what I found.

I have used descaling chemicals on production equipment for years (retired Process Engineer) and they are the way to go if you are attempting to clean your system. Just hooking up the hose and doing a back flush only goes so far.

This stuff looks to be agressive enough to push out the descale interval from 2 to at least three years. Yes I use distilled water instead of tap water and yes, I am a tad AR about engine cooling...
 
Interesting 0-gauge....my interest in the Rydlyme came about because of a broken plastic radiator tank 4 miles down Matagorda beach. We used all 13 gallons of fresh water+lots of stops just to get off the beach. Then a nice fellow let us have some water from his intracoastal canal house outdoor spigot..come to find out, it was raw wash water from the canal=brackish at best...we made it to Autozone and changed radiator+fresh coolant/water, but I undoubtedly had corrosion and my Jeep was running hotter after that. No coolant or oil loss though...

The interesting thing to me is that I had done a regular drive it around for several hours flush only about 6 months prior to the Rydlyme, and I still got a significant amount out....
 
I typically run my cooling systems for 4-5 years between coolant change outs, with no need for flushing, or aggressive chemical cleaning, unless the radiator encounters a drunk telephone pole, (LOL), or a POS China water pump dies way too soon, and then I do repairs as needed and replace the coolant early. But I also have little long term experience with new rigs using aluminum plastic radiators and other junk under the hood. Long term I have stuck with all copper-brass radiators and the old green Silicate based antifreeze coolant at 50:50 with DI water. I have no faith in the newer formulas.

I use descalers in the chemical process industry. I use to formulate descalers ( I am a Chemist-Chemical Engineer), and I know what is in them, and how cheap the ingredients are. $24/gallon for a descaler is way over priced in the automotive sector.

Most people would be amased at what 1 lb of sulfamic acid ($5.50 at Home depot) in 2 gallons of water would do in a short period, or a quart of acetic acid (food grade vinegar), in 2 gallons of water, but with aluminum water pumps, heater cores, radiators and heads all over the place in vehicles now days, you risk starting leaks in the heater cores, water pump shaft seals and radiators using any descaler that is capable of removing heavy calcium carbonate and calcium silicate scale from the engine block. That is why I never descale a radiator or heater core, I just replace it.

Now a 4.0 engine block being all steel, is another story, if you plan to replace the water pump in the final step.

boncrshr,

My comments are only about the 1 gallon snake oil (LOL) flush product cost, not the circulating system. But on the circulating system issue, there are pros and cons. Getting the engine good and hot (using gasoline to run the engine), heat cycling while descaling may have real advantages, while pumping that crap through the radiator would have real disadvantages unless one is replacing the radiator in the final steps.

Finally my perspective is a bit tainted, as I use to mix and formulate snake oil, mark it up 1000% and sell it cheaper than other snake oil sales people, LOL! I also do not like that the product you chose does not list the ingredients.

And I agree, taking the before and after temp readings was a good science based approach to measuring the results. But are you sure the cleaner did unstick, or unstop up a clog T-stat?
 
This stuff looks to be agressive enough to push out the descale interval from 2 to at least three years. Yes I use distilled water instead of tap water and yes, I am a tad AR about engine cooling...

Just one thought on that comment. If the engine head gasket is not leaking CO2 into the coolant and turning coolant silicate into concrete glass like scale on the block and head walls, and the coolant is mixed with only DI water, there should be no need to descale every 2-3 years when changing the coolant IMHO, especially in a closed Renix system (LOL, had to toss that one in there,LOL, as the open systems do see some CO2 in the overflow bottle.)

I have had vehicles that I ran for 5 years, with no coolant changes or coolant system service, that had no scale or corrosion when I opened them up. But I also take very good care of my cooling systems.
 
The interesting thing to me is that I had done a regular drive it around for several hours flush only about 6 months prior to the Rydlyme, and I still got a significant amount out....

My answer to that is it may have way too much contamination to begin with, and you may have used a light duty, versus heavy duty flush product the first time? It is also possible that more contamination formed during that 6 months, and that brackish water may have had enough time to react with coolant additives as the pH dropped forming tons of scale forming sludge.

What most people do not understand is that hard tap water reacts with silicates in the coolant, precipitaing calcium silicate (AKA concrete!) in minutes that scales up the engine and radiator when they get hot. I am not sure what the current 5 year, new coolant formulas have in them (some were using boron in the late 1990s) but they have some kind of pH dependent, reactive leak sealer ingredient in them that acts just like the old silicate formulas we used for 100 years, IMHO.
 
WOW, I found the MSDS, this stuff has HCl in it, muriatic acid, hydrochloric acid folks!!!!!

http://www.rydlymemarine.com/pdfs/RYDLYME%20MARINE%20MSDS%20%20JAN2008.pdf

I would never let this stuff near a cooling system!!!!

Bottom of page 2, MSDS has a strong warning about reacting with aluminum!
And the MSDS contradicts itself on the organic acid non-volatile claims versus the non organic <10% HCL acid listed as the only hazardous ingredient, then says it is safe (non-hazardous) to dispose of down the city sewers as received with a pH <3.0, LOL!!!! The MSDS is RED Flag!!!!!!
 
I went to the MSDS in the link in the first post,Mike, I,m suprised you missed that.
ACID, RED flag..... However I have used plain white vinegar as a cleaning agent/flush. We have very hard lime stone water,so its distilled water for me..
 
I went to the MSDS in the link in the first post,Mike, I,m suprised you missed that.
ACID, RED flag..... However I have used plain white vinegar as a cleaning agent/flush. We have very hard lime stone water,so its distilled water for me..

I was not looking for the MSDS the first time. It is not that it is an acid that I have a problem with. It is THE acid they listed, a very strong corrosive acid, HCl, I have the problem with. Vinegar is a weak organic acid, and much safer than HCl on metals.
 
This is why i found taking it to a shop is the best and the safest thing to do.They have the right stuff and it is done in a couple hours for about 45 bucks.Good for 4 to 5 years, mine doesn't over heat at all with the AC on with a stock closed system on it.It did when i first got it, now 4 years later it is running around 200 off roading in the desert with the AC on.(Palm Springs CA)

Find a good shop and let them handle it, it could be your kid or dog in that gutter down the road playing in the water on the corner.
 
We changed our thermostats after the flush, so it could be a variable...but the 10 degrees was pretty significant. As far as the flush I used previously....IIRC it was the Prestone one that you leave in for an extended period of time.

Rydlyme is all the rage here on the coast....guys with outboards swear by it, and I haven't heard of anyone having any negative effects....nothing but good stuff. You just have to remove any zinc anodes. We used the solution at 33% by the time we added enough water to be able to circulate the solution using the pump...which according the literature should lessen any potential reaction risks.

http://www.rydlymemarine.com/pdfs/SPEC2004.pdf

http://www.rydlymemarine.com/pdfs/MARINE MATERIAL COMPATI.pdf
 
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Just for my information, are you folks calling Distilled Water DI? For me, DI is Deinoized Water and cannot be used in anything that contains any sort of metal. DI water is used in the Integrated Circuit Industry (Process Engineer...) to clean the wafers. It will re-ioized by robbing the metal ions out of anything metalic it comes into contact with. DI water is piped/stored in plastic just for that reason. Once it hits metal, it is contaminated and is useless in the process. So, we used DI water spray rinses in the Fab.

It disolves metal if left in contact long enough...

I have used both the Prestone Flush and reagant grade Acetic Acid in the past. To be honest, I did not check the MSDS of the rydlyme.

Tap water contains an amazing amount of minerals depending on where you live. The better tasting the tap water is... the more minerals it has. Take a drink of distilled and see for yourself. Here, in the Springs, we have a ton of mineral and as a result one of the best tasting (now that's sure to start a fight) water in the country. Good for people, bad for engines.

Economike, as a Chemical Engneer, what is your opinion of the likelyhood of the minerals "plating out" of solution in the presences of Iron and 210F heat? What about the possibility of Galvanic Corrosion happening in the system?

I'm just an Electro-Mechanical Engineer. My degrees are in Electronics (ASET) and Mechanical Engineering (BSME). Chemistry is somewhat a black art insofar as I'm concerned.

What I do know is that using Steam Distilled Water will lessen the occurance of cooling systems corrosion.. This is just from Empirical data, not theory so I can't give the explanation for the processes involved.

And for those wondering, it is "0" as in Zero not "O" in my nom de web. As in 0 gauge model trains. As in a 650+ sqft layout in the basement with a better than 50 year collection model trains. Bad enough I do Jeeps (have 2, the 98 and the 48) but Trains? I must be mad...

And yes the Engines are all Steamers not a Sneezle on the layout.
 
Just for my information, are you folks calling Distilled Water DI? For me, DI is Deinoized Water and cannot be used in anything that contains any sort of metal. DI water is used in the Integrated Circuit Industry (Process Engineer...) to clean the wafers. It will re-ioized by robbing the metal ions out of anything metalic it comes into contact with. DI water is piped/stored in plastic just for that reason. Once it hits metal, it is contaminated and is useless in the process. So, we used DI water spray rinses in the Fab.

It disolves metal if left in contact long enough...

I have used both the Prestone Flush and reagant grade Acetic Acid in the past. To be honest, I did not check the MSDS of the rydlyme.

Tap water contains an amazing amount of minerals depending on where you live. The better tasting the tap water is... the more minerals it has. Take a drink of distilled and see for yourself. Here, in the Springs, we have a ton of mineral and as a result one of the best tasting (now that's sure to start a fight) water in the country. Good for people, bad for engines.

Economike, as a Chemical Engneer, what is your opinion of the likelyhood of the minerals "plating out" of solution in the presences of Iron and 210F heat? What about the possibility of Galvanic Corrosion happening in the system?

I'm just an Electro-Mechanical Engineer. My degrees are in Electronics (ASET) and Mechanical Engineering (BSME). Chemistry is somewhat a black art insofar as I'm concerned.

What I do know is that using Steam Distilled Water will lessen the occurance of cooling systems corrosion.. This is just from Empirical data, not theory so I can't give the explanation for the processes involved.

And for those wondering, it is "0" as in Zero not "O" in my nom de web. As in 0 gauge model trains. As in a 650+ sqft layout in the basement with a better than 50 year collection model trains. Bad enough I do Jeeps (have 2, the 98 and the 48) but Trains? I must be mad...

And yes the Engines are all Steamers not a Sneezle on the layout.

While the method of making DI and distilled water are different, they are both essentially ion free, as in free of ionized minerals, as the distillation process leaves the minerals in the boiling pot, the minerals do not evaporate and do not go into the condenser. DI water can still have trace organics that are not ionized, like benzene, but the organics can be removed by a final activated carbon filtration process. Distilled water can have non ionized organics as well, if they are volatile and boil like water at or below 212 F. They also can be removed by activated carbon filters. DI water is prepared by passing it through ion exchange resins that swap H+ into the water in exchange for a + ion like sodium or calcium or magnesium. The CO3-, SO3- anions are swapped for HO-, and the H+ reacts with the HO- to make H2O water.

Distilled water is just as corrosive as DI water. The antifreeze mixtures you add to the DI water add sodium Na+ back into the water, with SiO3- ions, silicate ions that raise the pH, and make the water non corrosive. The pH buffering action of the sodium silicate neutralizes the CO2 + H20 => H2CO3 carbonic acid, by forming sodium bi-carbonate, and a complex water soluble silicate. If the CO2 level gets too high (head gasket leak), the pH buffer action is overcome and you get a hard white carbonate-silicate scale forming on the metal walls that acts like a heat insulator.

Also note worthy, the solubility of calcium and magnesium in natural spring water (or well water) is inversely proportional to temperature, so as the water heats up the calcium and magnesium precipitate as a hard heat insulating scale on the engine block and radiator tubes.

Galvanic corrosion where aluminum is used with iron in the same common plumbing system is a huge problem with engines using aluminum!!!!
 
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How does RO water compair to distilled and de-ionized?

RO water is equal to about 3-5% tap water added to about 95-97% DI water, if typical tap water is the feed to the RO.
 
Thanks Ecomike I can always use more education and my hat is off to you Chem guys. It is all black magic to me. Now, if you want to talk about raising the valence level of a Flourine atom with a high voltage discharge so that when it collapses back it emits a 248nM photon, I'm game. Lasers, I understand after 25 years of fiddling with them...

My experience with DI is in the Industrial settings (I was an Intel employee (PhotoLithography) when I retired, among other lesser places) and we always piped the DI in CPVC to keep in well, deionized.

Shorty, I am totally mad. I have Locomotives that cost over $2500 new. My Southern Pacific Daylight Passenger set ran very nearly $5000 to put together. O-Scale Model Trains are one of the very few Hobbies that can be an investment. But you have to have patience. No surprise that these days it is good to be a buyer, not a seller...
 
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