Sanity Check - Pouring Pepsi into an engine!?!?

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vodzurk

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So my engine is running a bit hot. It's been through various diagnostics, with just a few potential causes remaining. One of which is crud/salt buildup in my seawater heat exchanger.

So I call a chandler, asking if they stock Salt-Away or Rydlyme.

Him: Never heard of it, what's it for?
Me: Flushing the seawater heat exchanger.
Him: Nahhh, just pour 3 litres of cola in, leave it 24 hours, then flush. Works a treat for me, brought my XYZ engine right up, it's perfectly harmless. You've seen what it does to coins, right? Polishes them right up.

So, I had a few pints last night... am I still asleep, and dreaming that this conversation happened? Or is it actually a good bit of advice?
 
vodzurk said:
So my engine is running a bit hot. It's been through various diagnostics, with just a few potential causes remaining. One of which is crud/salt buildup in my seawater heat exchanger.

So I call a chandler, asking if they stock Salt-Away or Rydlyme.

Him: Never heard of it, what's it for?
Me: Flushing the seawater heat exchanger.
Him: Nahhh, just pour 3 litres of cola in, leave it 24 hours, then flush. Works a treat for me, brought my XYZ engine right up, it's perfectly harmless. You've seen what it does to coins, right? Polishes them right up.

So, I had a few pints last night... am I still asleep, and dreaming that this conversation happened? Or is it actually a good bit of advice?
Click to expand...

I tried putting a coin into coke or Pepsi, can't remember which. Left it for a day or so, made absolutely no difference.

Get hold of some Rydlyme, it really does work.
 
I find sulphamic (NOT Suphuric) acid very effective, and very cheap from Ebay.

However, I think coke contains very weak phosphoric acid, so possibly it might work, but I wouldn't use it and would suggest this would be part of Roy Rogers Marine Engineering Ltd practices.
 
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I'm not sure it will be as effective as Rydlyme, but I doubt it will do any harm. As mentioned above, rodding the tubes with a straightened coat hanger might be required if it's very blocked. What engine is it?
 
Roding is quite harsh if you value your intercoolers.

Either Rydlyme your engine completely on the seawater side or remove the coolers and immerse them in Rydlyme in a plastic plant trough (like people have on window sills). Your intercooler stack comes out like new not pink like when people use brick cleaner which is too aggressive and damages the cooler.
 
Coke and Pesi used to contain phosphoric acid, but this "flavour enhancer" is no longer in European markets because of the damage it can do to teeth. Which is perhaps why an old chandler might have been right a couple of decades ago.


However, a quick peruse through the MSDS for Pepsi for other countries reveals that in Puerto Rico frinstance, Pepsi contains

Phosphoric Acid.... 1 mg/m3
Ethyl Alcohol....1880 mg/m3 or 1000 ppm
Caffeine....


Thus it looks as if the colas in some countries might be useful for cleaning engines. But what the sugar and aspatames do to your tubes , I have no idea.
 
Well, seems like I'm too late to pick any "proper" cleaners up online.

Patio cleaners seem to be phosphoric, as is the secret ingredient in Salt-away. But going off-piste, I don't want to use something too strong for took long.

Tesco does list phosphoric acid as an ingredient in cola. And https://www.sheltondentistry.com/patient-information/ph-values-common-drinks/ shows Pepsi/Coke as being top of the pops for acidity.

Looks like the way forward is to grab a laser temperature gun, check it today, flush through 4L of Pepsi, leave 24 hours, flush, check again.

Watch this space! :).
 
My mooring neighbour cleaned his heat exchanger at the start of the season with Flomasta Central heating cleaner. Tells me it's done the trick and pulled out an amazing amount of scale and salt deposits. I purchased some from ScrewFix - I'm not brave enough to try it though.....
 
Ah dammit... I left the sheet of paper with all the readings on on-board.

Engine was no longer overheating... Though we did other stuff too... But I took some readings where Cola was the only difference... Will post them in a few days.
 
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