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Discussion Starter #1
I want to flush this rusty coolant system with the garden hose technique and a cleaning product.

Would a product be safe to use on this old car?
Which technique of 'the garden hose method' should I use? I come across several methods on the web.
Which product would you personally advice using? Or which brand? I've got to see what they're selling here in the Portuguese countryside.
The thermostat appears to be stuck open. Is it recommended to change this ASAP too? Covid has got me poor. ;)

The system been rusty for 1.5 year already.
190181
 

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Technical Supremo, Platinum Member
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I wouldn't bother using a cleaning product ...... just flush the block and radiator with copious amounts of clean water preferably from a garden hose. Remove the bottom hose from the radiator and take out the thermostat and stick the hose nozzle into the thermostat aperture.
Refill with a good mixture of blue anti-freeze and de-ionised water. That coolant should stay clean for at least a couple of years.
The block being cast iron will produce lots of nasty brown water if its not had antifreeze/rust inhibitor in it for some years. Also check the thermostat has been fitted the correct way around (mine was wrong!). It still worked but the opening is impaired until the engine reaches a hotter temperature.
 
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Discussion Starter #3 (Edited)
Nice to hear from you again!
So having the engine running is not required? I just inserted the garden hose into the lower radiator hose, leaving the thermostat in place as my thermostat is already stuck open.
I did the the same having the garden hose into the coolant reservoir.
It seems to have ran clean. Will it stay clear after running the engine?
 

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Technical Supremo, Platinum Member
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No need to run the engine while flushing. If you are satisfied the water is running through clean, then when you refill with new coolant/antifreeze this should stay clear when you run the engine.
 

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Discussion Starter #5
No need to run the engine while flushing. If you are satisfied the water is running through clean, then when you refill with new coolant/antifreeze this should stay clear when you run the engine.
I filled the thing with water and started it up (to check if it whent muddy again), and a bit of white smoke came out of the exhaust when starting the engine. Could this indicate a internal leakage? It was only briefly. I already tought there was some some coolant missing after driving and it seemed to overflow out as well last times i drove(combustion gasses in coolant system?)
Bad news?

I might gonna run some distilled water through it to flush it a few times and then add the blue coolant mixture.
 

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Technical Supremo, Platinum Member
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I've no idea about white smoke in diesels. The water level should settle to a normal level quite quickly after a short drive. Any airlocks should clear themselves easily especially as you say the thermostat is stuck open so the coolant if flowing around freely.
 
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