I have a Toyota etios liva G (Petrol) car and took it today to a local workshop for first time instead of Toyota service center for replacement of coolant as I noticed the coolant reservoir tank was empty and this workshop was very close to my home. The mechanic there mentioned that he didn't had the right key to open the nut to drain the coolant from bottom so instead disconnected the flexible rubber pipe attached near radiator cap to drain the old coolant. ( pink in color). I had taken distilled water along with me as I had read online that you shouldn't use tap water to flush the old coolant. He then added the distilled water and started the engine, revved it for some time and then drained that too.
After this, he added the new coolant by company "Wurth" which mentioned "concentrate red" directly to the radiator cap and then kept on idling the engine and revving it in between and topping it again when the level would go down. On the back of the bottle it was mentioned to add 1:2 parts of water to this concentrate and I told him the same. He mentioned that they add the coolant like this only and the engine already contains water ( not sure what that means - novice here in automobile stuff). He filled the coolant reservoir tank too with the concentrate coolant till full mark without diluting it with water, I then objected to it and asked him to remove some of it and add water to the reservoir tank which he did ( around half cup of water)
Is this the correct procedure to replace coolant in the Toyota car? is it safe to drive the car in this condition? I'm not sure hence asking automobile experts and seeking guidance. I haven't driven the car much after this as the workshop is very close to my home. Please advise.
Thanks a lot in advance