caustic soda for cleaning?

[Albannach]

I've been using the search button!
If I remove the Thermostat and back flush the system from the bulk head with the engine running it should get most of the cr@p out! I'll let it flush through for ages then remove the radiator and flush that again

Don't run the engine! Where does it say to do that, and where does it say to flush from the heater hoses?

Back flush the engine with the engine off, thermostat out (but the cover re-fitted) and the heater set to maximum. Then back flush the heater separately. If the main radiator is choked, you'll not clear it by flushing.

[Bogus]

Well youve already been told not to use caustic soda, and that is sound advice. It agressively attacks aluminium and in the process creates hydrogen. Using any acid or alkali cleaner in a system where you dont know all of the materials it will come in contact with is usually dodgy, and quite likely to lead to things like core plugs falling out a few weeks down the road ( or worse)

I see you live in the south, if your cooling system has been neglected at all, ( run on plain tap water for example with minimal or no coolant at any time) you could have limescale build up. If you really want to use a "chemical" citric acid would be the one to try as long as you gave it a good fresh water flush afterwards to get rid of the acid. If I was living down your way, Id be putting demineralised water in the system. Your tap water is disgusting compared to our fine Scottish stuff

Bogus

[puddlesurfer]

I did read it somewhere on here about having the engine running whilst flushing - but I won't if it's a bad idea (i won't use caustic soda either) as for the water quality down here - you're right it disgusting - I have to drink beer instead!

[puddlesurfer]

I just searched again and can't find where it said to have engine runnig so maybe I drempt it! my bad!

[gwh200]

Well youve already been told not to use caustic soda, and that is sound advice. It agressively attacks aluminium and in the process creates hydrogen. Using any acid or alkali cleaner in a system where you dont know all of the materials it will come in contact with is usually dodgy, and quite likely to lead to things like core plugs falling out a few weeks down the road ( or worse)

I see you live in the south, if your cooling system has been neglected at all, ( run on plain tap water for example with minimal or no coolant at any time) you could have limescale build up. If you really want to use a "chemical" citric acid would be the one to try as long as you gave it a good fresh water flush afterwards to get rid of the acid. If I was living down your way, Id be putting demineralised water in the system. Your tap water is disgusting compared to our fine Scottish stuff

Bogus

I've seen the municipal supply on the Scottish east coast. The influent is a stunning example of aeon filtered liqor. Unfortunately, by the time it gets to the tap, via the antiquainted fresh water system,and it's Been treated with Scottish water's disinfection favourite,clorus (bleach to Me and thee)...well I tendedto drink bottled water when further east than Stirling.

[dieselboy]

Your tap water is disgusting compared to our fine Scottish stuff

Bogus

You're not wrong. I have to rinse our work kettle daily and watch the flakes fall out into the sink.
Seams to be better where I live though.