H2

I already know that very few people on this forum would even think of using Lime-A-Way to clean their coolant system. I've not done it but a friend of my was experiencing overheating and poor interior heating and he ran 28 ounces of this stuff in his late model Cadillac Catera (Volvo engine, I think). He ran it for 15 minutes, then emptied it out and flushed his system numerous times with cold water...and voila', the plugged heater core opened up and the radiator started cooling better. No more cooling issues. He's not advocating it but swears it worked for him.

Although what I can see of my S4 cooling system appears to be clean enough, I was intrigued. I read the fine print on the Lime-A-Way bottle and (concerning aluminum) it says (among other things) "Do not use on polished or anodized aluminum." So, I got to thinking, maybe it would dull or etch polished or anodized finishes, but with only 15 minutes use, PERHAPS it might dissolve hard water build up (The bottle print claims "to dissolve lime, calcium, and rust"... and maybe open up some clogs?)

This stuff is not designed for cars but rather to clean plumbing devices so I AM NOT RECOMMENDING ITS USE. Nevertheless, given my friend's experience (I witnessed it) I wonder if it could indeed "boil out" a 928 cooling system without damage if used carefully, quickly, and flushed out exceedingly well with fresh water afterwards.

At any rate, I have a pleased friend whose cooling system has a lot of aluminum in it and he swears that this stuff "fixed his cooling problem." He was on the verge of having a new heater core installed ($$) and tried this as a last ditch stand.

Has anyone tried this or are you like me, you don't dare because someone said not to but they hadn't actually tied it?

Akin to this, I've always wondered how someone would clear out a shop rag that might be lodged in their cooling system?

H2

Mrmerlin

A word of warning,
adding any kind of cleaner to the 928 cooling system especially on a car thats got 20 year old head gaskets will greatly speed up the possibility of the headgasket failing due to it cleaning out the system, as the head gaskets are actually exposed in the cooling system ,
plus the radiator O ring seal may also be damaged by the cleaner thus it may spring a leak

RKD in OKC

my nephew would run radiator cleaner in every used car he bought, then not understand when the freeze plugs would start leaking.

joejoe

I used CLR on my 944 radiator when it was out for w/p, belts, rollers. This car ran just above first line on temp guage before and with the CLR treatment ran just above the first line still. I did not have any heating/cooling problems before however, and the tubes in radiator(that could be seen) were clean before treatment. Not sure if the stuff is good for engine internals as mentioned above.

Jim M.

Mercedes uses a "Citric Acid Cleaner" and they use just as much aluminum as our cars. P/N A 000 989 10 25. Drain the coolant and rinse a few times. Add some liquid Tide laundry detergent and run it up to temp to de-oil the system. You must de-oil before you use the citric acid whether you need it or not. Rinse the system well a few times. Dissolve the citric acid in a bucket of warm water and pour it in. Fill the system, run it up to temp and rinse very well. Add coolant and you're good for three years.

jbrob007

Guys, the base ingredients for Liquid Tide & Liquid Cheer - both made by P&G - are Ethyl Alcohol (Ethanol) and Sodium Hydroxide (Flammable Liquid, N.O.S., 3, UN2924, PGII) - dont ask me how I know Not sure if I'd be putting even a little bit of Sodium Hydroxide in anything aluminum... much less industrial strength Citric Acid (one base / one acidic - both highly corrosive). I dont know about our engines, but I do know Sodium Hydroxide will eat through a Railroad Tank Car's 7/16" carbon steel plate (much less aluminum plate) in short order.

Your call... I'll stick with changing the antifreeze on a regular basis and calling it a day

Joel

Mrmerlin

just in case you didnt read this I will post it again

A word of warning,
adding any kind of cleaner to the 928 cooling system especially on a car thats got 20 year old head gaskets will greatly speed up the possibility of the headgasket failing due to it cleaning out the system, as the head gaskets are actually exposed in the cooling system ,
plus the radiator O ring seal may also be damaged by the cleaner thus it may spring a leak

danglerb

Radiator comes out pretty easy. Pull and have it hot tanked or whatever it is they do, and back flushed.

ONLY use distilled water and quality coolant, so where would the lime be coming from anyway?

z driver 88t

That's what I would be wondering. Unless hard water has been used for the cooling system, there shouldn't be any Ca deposits.

I wouldn't hesitate to pull and flush the radiator with some sort of descaling compund (I 'm guessing the stock Behr is just a copper core? Not sure) - but wouldn't be comfortable running it through the block.

H2

Yes....but did the previous owner use regular tap water? Those who live in warm states sometimes tend to do this. All 928 owners are not conscientious.

Because of what MrMerlin says, I'd be afraid of messing up the head gaskets. However, pulling the radiator is a possibility but, remember, those side tanks are probably easily damaged and could leak if you're not really careful.

Adamant1971

Also most lime away products will pit the metal slightly, wouldn't want to do that too my engine.

NoVector

+1 Used radiator flush when I first bought the 84 thinking I would be a good steward. Next thing I know, I’m sprouting all kinds of leaks: transmission cooler, hose seals, and then the head gasket. On a positive note, I learned how to replace a radiator, all the hoses and do a top-end refresh w/ new head gaskets.