Top up car with just coolant instead of water?

[Blue Oval84]

I've got a very slight coolant leak which I don't have time to get fixed at the moment. Am I right in thinking that rather than water the coolant down it would be safer to top up with just pure coolant?

I imagine that having the coolant mix too strong as opposed to too weak couldn't do any harm? Wanted to check before I did it rather than chance doing something silly though

If there's a problem doing that then I'll need to start doing the proper 50/50 mix I suppose but I really can't be bothered to start getting watering cans etc. to the car when I can just pour in pure coolant!

Thanks!

[Chrisw666]

Just put water in.

It will freeze and block the leak.

HTH.

[Krikkit]

Get an old 5L water bottle and pre-mix yourself some 50/50 for topping up?

[aka_kerrly]

Chrisw666 said:

Just put water in.

It will freeze and block the leak.

HTH.

I think what you meant to say is, in these rather cold conditions if you only have water in your coolant system it will freeze and potentially crack the block causing an even bigger leak!!

I had three cars to work on last year where the coolant or rather 99% water mix had frozen in the coolant pipes to the extent that every rubber hose, the expansion bottle and radiators needed to be removed and defrosted!

[Benrad]

The only problem with too strong an antifreeze concentration is that it cools the engine less efficiently. In this weather that shouldn't be a problem.

Make sure new coolant is the same type (colour) as the old, never mix different types!

But tbh just mix some up in a jug and keep it for topping up, make sure no pets can get to it though

[aw51 121565]

Benrad said:

The only problem with too strong an antifreeze concentration is that it cools the engine less efficiently. In this weather that shouldn't be a problem.

Antifreeze has a lower specific heat capacity, to formalise Benrad's comment. A stronger antifreeze solution is also more viscous than regular diluted antifreeze, which means potential circulation problems and possible hot spots in the cylinder head (due to heat not being taken away as fast as it ideally would be) which isn't an ideal situation.

The occasional splash of antifreeze will be fine, but I wouldn't want to be slinging in a pint of neat stuff every day - premixed 50% antifreeze would be recommended if the leak needs replenishing more than once a couple of months.

[sa_20v]

Didn't Ed use something on Wheeler Dealers that never needed to be replaced and dropped temps in comparison to standard water/anti-freeze mixture? No idea on it's capabilities in Winter but worth considering?

[MattTheCat]

Yep this stuff.

http://www.evanscoolants.co.uk/

[Blue Oval84]

Ah, I see, thanks for the advice guys, will get some coolant from ECP later, it's the orange coloured one so I know to make sure I buy the same type!