SHOUT for coolent flush? MB recommended!
 

1982 300D

While attending a MB tech session at our local dealer they mentioned using SHOUT (that's right... the stuff you get in the grocery store) for flushing out the cooling system. They use it 1:1 or 1:3 depending on how dirty the system is. They use it when they have fixed a head gasket etc. I confirmed this with a 2nd MB dealer!

Has anybody else heard this?

The MB CDs do say that before using any chemical scale removing solution that it is necesary to de-oil the cooling system but they don't say what to use. They do suggest a 10% citric acid solution for the descaling. Where can we get this? I know that white vinegar is 5% ascetic acid, but don't know if this would work.

Thanks... Mr Goodfahrt

observation
 

on the 1 to 1; shout ain't exactly cheap. especially in 4-5 quart quantaties.

$4.29 for 60 ozs!
 

Right you are... it ain't cheap! Any suggestions for a substitute?

Mr Goodfahrt

The citric acid is available from your local MB dealer. See this thread for details.

Can you detail exactly why the techs recommended Shout? Are they using it as a surfactant? If so, I've heard of people using dishwashing detergent as a substitute.

Citric acid is available from cooking, canning and confectionary suppliers fairly cheap. I have about 5lbs. left from doing several cars, if anyone in my area needs some.

Citric Acid
 

Isn't citric acid just plain old Vitamin C? :confused: If so, you can buy powdered Vitamin C at any large drug store; just be sure you get the powdered kind that is 100% pure. You can also get it at Trader Joe’s. It's fairly cheap.

M.

Nope. Vitamin C is asorbic acid. Citric acid is the main ingredient in Prestone Superflush.

I use 10% citric acid in the lab to clean light rust off metals. It removes the rust and leaves the metal alone. But be careful, the citric acid must be completely flushed from your cooling system or it'll eat away the metal.

Ok then, why not just use Prestone superflush? I've been wondering about this for some time. I'm aware of the differences in coolant and, in fact, I'm probably one of the biggest proponents of genuine MB coolant on this board. But the flush is just a cleaning agent and doesn't stay in there very long. So why not just use the flush that is inexpensive and readily available at the parts store?

You could lower the cost of Shout by purchasing it at COSCO or Sam's Club.

Howdy,

I wonder on flushing: The shout is soap and is use to deoil the cooling system. The ascorbic acid is then used to remove any corrosion and scale buildup that might have occured.

I think these operations are distinct and if you have blown a head gasket, you should deoil before you descale/clean.

I used a little dishwashing soap, but that is a little too sudsy. Laundry detergent would be much better.

Sholin

I'm still waiting for a comment on Ricks question. Why not just use Prestone Super Flush? Seems reasonable to me.

That's actually what I did on my 190D 2.2. It had a gasket failure and filled the cooling system full of oil. I deoil'ed (probably ineffectively) with dish soap and then used prestone superfush.

Seemed to work OK for me.

Sholin

Dawn cuts oil quite well. This is one product that actually lives up to its advertising.

degreasing with low sudsing and Sniff Test
 

I think the reason MB techs recommended the SHOUT was because it is a low foaming/sudsing product. A generic brand would be more economical if it had similar characteristics.
Any suggestions?

When doing the flush it needed many "rinse cycles" to remove all of the soap. I also was draining the block drain to be thourough. Maybe the sweet smell is why they use it.... you can tell when it has been rinsed out by sniffing.

Mr Goodfahrt

Carpet shampoo for steam cleaners is formulated with low sudsing agents - $12/gal at ACO Hardware.