radiator sealed and garage topped up with water

[lavalovely]

Morning all, looking for some advice on my A3 1.6  (53).  My coolant warning light came on so I checked the tank and it was empty!  Topped it up but it emptied itself over a bit of time onto the driveway.  I couldn't get my usual audi specialist garage so went to another garage I've used before for routine stuff.  They diagnosed a hole in the bottom of the radiator so did some work to clean through added a radiator sealant, then topped up fully with water so I could drive the car in the short term until I get radiator replaced. 

My concern is having water in the radiator now where I've always used  an Audi recommended coolant (can't remember name but it was blue fluid).  Will water cause damage if I drive it?  Should I get the water drained and get my usual Audi recommended coolant put in?  Or can it be mixed (probably a silly question but putting it out there).  

I also need to make a long journey of 200 miles each way in the next week or so, is the car fit for this type of journey?

thanks and have a great weekend!

[cliffcoggin]

As a short term measure until you get a new radiator plain water is perfectly fine and will do not the slightest harm to your cooling system. The coloured coolant you refer to is a mixture of water, anti-freeze (ethylene glycol), dye, and a corrosion inhibitor. The anti-freeze component is in it for obvious reasons; the corrosion inhibitor is essential for long term use to prevent the electrolytic corrosion which occurs between the different metals in the cooling system, (aluminium, copper, steel, zinc.)

Whether the repair will survive a 400 mile round trip is unknown. It really depends what sort of sealant was used, how big the hole was, and whether that part of the radiator is under enough stress to open up the repair. What concerns me equally is the thought of all that sealant circulating round the cooling system. I don't know if modern sealants are any better, but at one time there was a fear of it clogging up the narrower water passages in the system.

In your position I would certainly not trust the car for anything more than a few miles at a time on non-essential journeys. Get the train instead.

[Magnet]

Hello C.?

OK, you have established your radiator has a hole in it, and that the radiator needs replacing. 

We know you have added  Radweld or similar to your now highly diluted coolant - now substantially water, but still with a blue tint? 

We know you intend to make a 400mile journey in this car, before renewing the radiator. Bad news, obviously chance taking, with the potential for being stranded at the roadside, and at the mercy of whatever local garage to charge you -whatever- to sort it out. Assuming you haven’t toasted the engine in the process.  We assume you have breakdown cover?? 

Is there any good reason why you cannot renew the radiator before making the journey? If that reason is cost based then see above for potential costs. 

Re coolant:- 

‘Audi recommended and blue in colour’. This confuses, since most manufacturers were using red/pink OAT coolant around the time your car was new. Ethylene glycol and red OAT are two different coolants and should not be missed. To attempt to do so can result in the coolant coagulating, with obvious consequences. 

Personally, I would not use the car for this journey, but only you know the severity of the leak - but it sounds substantial from your description. 

I would certainly recheck the correct type of coolant, and if found it should be OAT, then the system needs to be thoroughly (in caps) flushed before changing to OAT. 

Kind regards,

Gareth.

p.s. Personally, I would not be too hung up about the use of Radweld etc. short term, since it is designed to be air hardening, so should remain in solution otherwise that at the leak site. 

 

[cliffcoggin]

4 hours ago, Magnet said:

p.s. Personally, I would not be too hung up about the use of Radweld etc. short term, since it is designed to be air hardening, so should remain in solution otherwise that at the leak site. 

 

Fair enough Gareth. It's been forty years since I used a sealant like that, and I have no doubt technology has moved on since then.

[Magnet]

Now modern K Seal etc. Cliff - probably another story! 

Kind regards,

Gareth.