Coolant water

I can only speak for me and I would say I have only ever used plain tap water (and we also live in a hard water area) in our cars [1] and vans. In our motorcycles I tend to used ready mixed 'coolant', simply because I can get it at trade prices, feel it's 'safer' to go with the recommended stuff as they aren't generally just cast iron ... and they generally don't use as much as a car?

Ironically we often run a de-humidifier and so I regularly tip reasonable quantities of what may be a softer / better coolant water down the drain?

Cheers, T i m

[1] 27+ years ago we built the kitcar from a 1978 MkII Escort and recently I had the heater radiator out to replace the electric fan. Whilst there I flushed the matrix and apart from a bit of general cr*p that washed out it was far from being anything like blocked in spite of being run on tap water all the time we have had it?

Back in the early '90s, Citroen had a lot of problems with porous blocks on CX turbo diesels. Some parts of the country, it was damn near every car. Others, it was almost unheard of. What was happening was that the impurities in tap water were causing impurities in the recycled scrap used to cast the blocks to corrode out.

So, yes, it can be a problem - or, rather, it might exacerbate an existing problem. If you're really picky, just buy pre-mix coolant.

I was told very many moons ago that DI water needed a corrosion inhibitor if used as a coolant in systems with carbon steel, aluminium and some other metals. But I've always assumed that the corrosion inhibitors in the coolant took care of that given the price of the stuff.

Water from the condensing tumble drier.

Liable to be a pain if they don't, though.

Ours doesn't condense, so that option is out. We do have a rainwater butt, though, which is a good thought.

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The manufacturer's recommended coolant diluted with tap water.

The additives in the coolant will comfortably take care of any variability in the water across the UK.

As an aside, in the days when batteries needed topping up, I only ever used tap water after I found it was acceptable in virtually all parts of the country by Rolls Royce amongst others. I have done this since the Sixties with no issues.

Chris

Since this is an aftermarket aluminium head, installed on a cast iron engine block, there is no definitive manufacturer recommendation, so I am starting from scratch. I can use either very hard tap water, or softened water, both from my kitchen taps, though.

Hopefully, yes. But I am trying to find the 'best practice' option, while being surprised by the suggestion to use De-ionised water.

I would agree with that, I never bothered with distilled water either.

I have an SD1 Rover with the all ally V8. Some steel pipes and of course a copper rad. I've had the car since 1988.

It has only had the correct anti-freeze and tap water all year round, changed about every couple of years. I live in London, and have no water softener. I recently changed the water pump, and the inside of the water jacket then exposed looked like new. No sign of any scale or corrosion. What you do need to avoid is the modern long life 'organic' antifreeze - usually pink in colour. This can attack some metals used in older cars.

BTW, which ally head? I've seen pics of a B-Series one on the MegaSquirt forum, and wondered who made it? Many years ago, VW Derrington sold a cross flow 7 port.

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Use an antifreeze as advised for an 'O' series engine, mixed with softened water?

Chris

Ally heads on iron blocks were very common at one time. The classic Jag XK engine, for example, dating back to just after WW2. And loads of others - even BMW up to about the mid '90s.

You'd generally use an antifreeze or additive suitable for ally, which will also be OK with iron. It was using plain water, or the original antifreeze made just for iron block engines which did the damage to the ally.

I used Halford's anti-freeze concentrate for older ally engines for many a year plus London hard tap water. But recently they've discontinued it and gone for a ready mix which of course costs more.

I'm now using a concentrate bought from EuroCarParts.

It is an early Derrington head, actually made by HRG for the "B" Series engine. The HRG logo is cast into the front of the head. Since the engine is installed in an HRG, it is quite appropriate.

I was considering that one myself. Thanks.

Very nice.

They recently had a deal on 20 litre drums of the stuff, so I bought one, since I have a branch close. Should see me out. ;-)

Ah - right. I did wonder if they'd been re-manufactured? Plenty want to inject the B Series, and port injection can be tricky with the siamese original. The four port should make it (relatively) simple.

The trick some seem to do with the A series is to fit a bike 16 valve twin cam head. Think from BMW.

How could this be Citroen's problem? Any car under 1 year warranty would have had factory or dealer coolant. Coolant change interval for '83 BX was 36K miles so a '90s CX would have had change at least that long. Unless they were built pissing coolant out and were topped up with tap water by the owner.