I’ve a 1996 1.8 Mk1. The original radiator split recently, and I’ve replaced it with a new aluminium one. At the same time I changed all the original coolant hoses, replacing them with silicone ones from Stoney Racing. ‘SR’ advise that not all types of antifreeze are compatible with silicone hoses, and publish a list of those they recommend. Using this, I’ve bought 10 litres of FL22. However, I’ve a nagging doubt that this may not be compatible with the car itself as I’ve seen forum messages saying it was designed for use in Mk3’s (NC). So, two questions…
Is FL22 suitable for a 1996 Mk1?
To get rid of any trace of ‘what’s in there now’, I need to flush the block - can I do this with tap water, ie: fill the system, run the car and then drain it?
I was advised on OAT coolant in a Westfield I built would be an issue, even though the factory supplied silicon hoses and I followed suit with other hoses to not be rubber. I regulary checked them internally and never saw any degradation of the hoses and never seemed to suffer any issues.
I personally wouldn’t worry too much about flushing the system unless the coolant in there is really manky. But if you want to, then tap water should be OK to use but in a perfect world, distilled water would be preferable.
You’ll only need 5 litres of coolant for a straight drain and refill, as you have 10, you could fill it with 5 litres, plus a bit of distilled water, run it for a bit then drain and refill it with the other 5.
Thanks - I think you’ve answered both my and CBRDeano’s questions!
The reason I was going to flush the system is that I don’t know what was used the last time the coolant was changed - it was red, but dirty. So I was going to fill the system, run the car to operating temperature to get the heater involved and then drain it. Apart from getting rid of any old stuff / crud, it would highlight any leaks before I put the ‘real stuff’ in. Yes, I guess distilled water would be best, particularly after having gone to the time and trouble of replacing the radiator, getting it to fit and fitting new hoses.
I’ve actually fitted a Japspeed 50mm radiator which has a higher capacity than standard - I think it’s about 6.5 litres in total (?)…
Very many thanks for your reply which has certainly put my mind at rest about using FL22…
If the stuff in there is red, dirty or not, then I would flush it. I’d actually drive it for a bit, allow it to heat cycle a few times rather than just let it reach operating temperature, before draining and refilling too.
Robbie, I just wanted to say thanks for the advice you gave about this, and so quickly. It was really helpful - it’s a great service you / the club offers it’s members, and alone is easily worth the subscription.