Restoring a badly neglected cooling system

I finally decided that I was done with topping the coolant up in my Jeep. I've soldered up the radiator, and now it should be 100% leak free. Because I had the whole system apart, I've decided it's time to get it clean. I cleaned it up as much as I could last time I had it open, but it was almost as nasty now as it was then.

Before I bought the Jeep, it had a blown freeze plug, and was only being filled with clear tap water. As a result, everything is crusty and rusty. I have the radiator as clean as it's going to be, but the engine itself is worrying. If I touch anything in the cooling jacket, it flakes off down to base metal. Is there anything I can do to get rid of this gunk? I am trying to avoid a rebuild, because this Jeep just isn't worth that much work.

vinegar. No seriously. I have heard of people flushing a system with a vinegar mixture as a mild way to clean out the junk you're encountering. With the oil, you'll have a rolling salad.

I'd go with a 30% mix, bring to temp, let run for 1/2 hour, and then flush.

Sounds like you might want a filter in the system - otherwise some of that crap will be floating around in there.

Of course, its a jeep and may not be with you forever . . . .but I try to take care of things (can't afford a lot of "fun and games" )

thanks for the vinegar tip!

Well, if I keep the Jeep around, it will eventually hit the point where an engine swap will be worth the time and money. Right now, the body is just not solid enough. I plan on fixing it, but not now.

I'm assuming you mean plain white vinegar, right? I don't need to get some fancy red wine vinegar or some good balsamic vinegar? Just joking of course.

My concern with the vinegar is it being too aggressive. I guess a weak mixture won't do anything majorly bad. I mean, it's already pretty gross. I'll probably treat it afterwards to get rid of the acid in the system.

I had a boss that dumped a few bottles of clr in an engine and spun the water pump with a drill for a few min.

CLR makes vinegar look like pure water; if the scaling/damage is that bad, then you just might want to set up a reverse flush through the engine for a half hour or so of just running clean water through the block to get the majority of the gunk out. Vinegar that diluted is very, very mild. CLR, OMG, that stuff is strong..

Bypass the heater core, undo the hoses to the radiator, remove the thermostat, and just let water flush through for half an hour. You don't need high pressure or flow, just enough to keep water going backwards through the system--you can adjust the amount needed by constricting the output hose.

Whatever you used to flush the radiator is safe for the engine, too, might want to try using that, too.

If you do go the vinegar, it's the imported, top-shelf Balsamic. !

I just used water in the radiator. Being able to shake it up helped, as did taking a torch to it for the soldering. It's temporary at best, but should last me until the summer is over at least.

According to my research only a 12 year oak barrel aged balsamic will work for flushing purposes.

I once changed the thermostat and coolant in my mercedes and had a piece of junk come loose and ended up clogging the radiator, what a simple job that turned complicated. On the mercedes I run some detergent through the system first to clean out oil and gunk, you can use a non-sudsing soap or TSP to clean the oils out. Then you use citric acid flush which is just prestone or whatever. I see that I bought some "eco friendly" dish detergent and it is just a pasty citric acid which I bet would work fine, don't know how acidic the detergent is though.

Good luck and watch out for going to "all out" on it and clogging the radiator with junk.

CLR sounds promising for the engine block flush but what about chunks getting loose and blocking up the rad? Is there a procedure for using CLR circulating in the coolant system w/ the engine running?

CLR ...bad if aluminum is present.

Vinegar works well, don't worry about it being to strong. You big problem was the leak and the tap water. I always start with a good flush.. Usually pop the heater hoses off and hit them with the garden hose using the little brass hose repair end from Tractor Supply (or wherever). Switch from one hose to the other just for fun. I try not to flush from the engine into the heater core...unconfirmed theory of big crap settling in the heater core I guess.

Disconnect the lower radiator hose and repeat my OCD dance with the hoses. Then I flush through the heater core excessively.

Button it back up, gallon of vinegar(2 or 3% concentrate), top with water and run it till I am sure that it is circulated and no air bubbles then leave it overnight. If you need to drive it to work the next day before you proceed it should be no problem either

Next day I repeat all those flushing steps including the flushing the radiator from upper pipe to lower pipe by pulling all the hoses again. Check and clean out the overflow tank, check the cap. Back together with a 50/50 blend with distilled water and you should be good to go.

Stay away from tap water when possible when topping it off.

If you have ever boiled a pan of water dry on the stove there is always an odd stain left that defied removal. This is what you are putting in your engine.

Bruce

The only time I ever put tap water in a cooling system is when nothing else is available. That stuff is the main reason I have so much crud in my system.

I've done all of the clean water flushes I can. The water is coming out clean now. I know it's still dirty because I can see the stuff behind the thermostat housing in the head and I can knock it off with my fingers.

As far as I know, there's not a single scrap of aluminum in the cooling passages of that motor. The radiator and heater core are as clean as they're going to be until they get replaced. The motor is the only thing left that's really nasty.

So the radiator is out? That makes it easier.

Tape the bottom hole on the engine. Fill it to the top with a CLR mix, let it sit for a day or two.

Back flush it with a garden hose hooked up to the sink spigot so you can get the water warm. Flush and have fun.

Repeat as necessary.

Now that sounds easy. Yeah, the motor doesn't have any cooling parts attached.

How strong do I need to mix the CLR? 1 bottle and the rest with water? 50/50? Full strength? I don't think full strength would to anything more than mixing it, but I can see it cleaning it up faster.

Dunno any precise CLR mix ratio. My very high tech CLR application to the Miata (complete with aluminum engine parts and a plugged up heater core) was one jug (unless it was actually two), and a day or two of sitting.

Fwiw, I'd soaked some spare aluminum bits I had laying around in CLR to see what would happen to them prior to using it in the Miata. Nothing. Nothing happened at all. I soaked them for days in a tub of straight CLR, and a diluted mix. I even dropped in some steel to see if I could get a good galvonic reaction happening. Nothing.

If I may ask a dense question - what is CLR? Just like in case, I need to work on the cooling system of my CJ7. Which happens to be on the agenda later this year.

Calcium

Lime

Rust

It is used to remove stains and etc from bathrooms.

http://www.youtube.com/watch?v=dqvDD_L7Y_M

BoxheadTim wrote: If I may ask a dense question - what is CLR? Just like in case, I need to work on the cooling system of my CJ7. Which happens to be on the agenda later this year.

It's also a decent Margarita mixer. (not really)

Ah, OK. Thanks.

I withdraw my aluminum warning. After a bit of research I have found that while the package does recommend not to use it on aluminum and copper, this is because CLR will strip common coatings from these metals....what the coatings are, I don't know.

Aluminum oxide from aluminum, which is technically corrosion. It's present on all aluminum and forms a hard, protective layer on any exposed clean aluminum. That's what I bet it strips off.

I'm going to try citric acid first. That seems to be the safest bet. I'll move on to CLR if needed.

Well, I decided to tape pics of what I'm working with here. This shot is right behind the radiator housing in the head. It's an iron head, just for a refresher.

I did pick up some cleaner. It's meant for dishwashers. I have the cooling system temporarily sealed back up, and will be flushed tomorrow. I expect to have to pull the radiator back out to flush again. Right now, I don't care what I have to do, I want it CLEAN.

Seems like this stuff would work too:

http://www.evaporust.com/evaporustcsc.html

When you say citric acid, does this mean you are using a packet of lemonade Kool-Aid? Unsweetened of course. No, I am not kidding.

CLR uses Lactic acid. Vinegar is acetic acid. Citric acid....Phosphoric ...muriatic..all have different properties and hazards. I have fought my way through the chemistry, terms and processes and it can get overwhelming quickly.

From the pictures, I see an easy cleanup with citric or vinegar...just depends on if you like pickle smell or lemon smell better. I know a few times I would have killed for water passages as clean as those!!

Bruce

Those passages are clean I don't fall for that for a second :p. I have seen worse, though. I'm hoping this will help with my overheating problem. It's not a major overheating problem, but it runs warmer than it should.

After I filled my temporarily sealed system up, I noticed a couple more radiator leaks. I would just replace it if I could afford it. If I have to, it will be an Advance Special because they're far cheaper than I can have one built for. That $30 coupon code is awesome.

I'm expecting this stuff to clean out most of the scale itself. I'm not concerned if it doesn't 100% clean it, but I want to get rid of all of the scale that's loose. Almost everything you see in those pictures above can be knocked off with your finger. I KNOW that stuff will end up blocking either the radiator or the heater core.

Alright, an update. The dishwasher cleaner stuff I got worked well. It didn't get it 100% clean, but it's at least 80% cleaner. I can deal with that. I still need to fill with coolant, but I expect the coolant to stay pretty clean from here out.

One bonus from the whole 3 week project is that I've gotten rid of my miss. I had about 2 dozen bad splices that I fixed. I've rebundled the harness, cleaned every connector, and greased every connector on the passenger side engine bay of that Jeep. I cleaned up 2 grounds, but the engine ground needs to be redone. It's a pain to get to, so I kinda need to get power tools back there to clean it up.

My next project is the 4 wheel drive system. I don't think I'm going into 4 wheel drive at all. The transfer case is shifting, but the axle isn't locking up. It's vacuum driven, so I will have to look at that. 2 vac leaks were fixed when I was under there, so I expect several more.