I am looking to change the coolant on my Mk1 and have become totally confused with the different types of antifreeze available.
Could someone out there point me in the right direction please.
Ordinary ethylene glycol antifreeze (usually blue or green) is fine for a Mk1 or Mk2.
Don’t use OAT (organic acid technology) antifreeze as it has been blamed for damage to parts made from “yellow metals” eg. heater matrix.
Also use distilled or de ionised water rather than tap water, kinder to the engine, less chance of furring up.
Thanks Bannedbiker,
Any thoughts on using a radiator flush, I have read some horror stories elsewhere regarding failed head gaskets?
Just found this.
http://www.opieoils.co.uk/pdfs/tech-articles/coolant-antifreeze.pdf
I do also seem to remember that there was talk that blue antifreeze contains silicates that are said to damage water pumps on Japanese engines. So looks like a green antifreeze that’s not OAT.
Probably best idea would be to go with the antifreeze manufacturers recommendations.
Easy option? Go to Mazda dealer and see what they recommend.
Regarding flushing, I’d undo top and bottom radiator hoses and the thermostat so you can reverse flush the engine and radiator. Watch the radiator if it has plastic tanks as they can get brittle with age. Quick check to make sure the radiator isn’t blocked is to feel across it’s surface to make sure it’s evenly heated; any cold spots mean a blockage in that point.
I haven’t had to use a rad flush so can’t comment on them I’m afraid.
Hope this helps,
Martin.
Thanks Martin,
The reason I am asking about flushing is long, but basically shortly after purchasing the car last year the head gasket blew. The dealer opted for an engine replacement which gave me an 85000 mile engine instead of 120000 so I was ok with that. Unfortunately they did not clean out the cooling system so there is still a trace of oil which I would like to get rid of, hence the thoughts on flushing. The water is basically clean but has a film of oil in it, I have some engine degreasing fluid and am also wondering if I could flush with this.
Thanks again for your thoughts the opioils facts sheet is most useful.
Dave
A Mazda dealer should be able to sell you Mazda’s Super Coolant in a 5 litre can, it’s pre-mixed and cheap as chips.
From what you’ve said it would probably be beneficial to flush the system using a rad flush.
I would stick to a proper rad flush rather than use something that hasn’t been designed for the job.
Good luck!!
Yes will stick with rad flush and look into Mazda coolant, thought it would be expensive hence looking at after market brands.
Thanks again.
I had an overheating problem with my Mk1 and used Holts Rad Flush. It’s a 2 stage process, takes about 1 hour to do and costs about £15.00. The results were excellent. I ran the car to the National at Gaydon without any problems and no sign of any overheating, even at motorway speeds! I’ve since taken the car off the road for a winter refurbishment and the first job was to strip down the cooling system and there’s no signs of any gunge or debris anywhere, so I’m pleased with the flush results.