Is the expansion tank cap actually the radiator cap, or am I missing something??
2009 model ready for a change and thought I might do the job at the same time as the oil/filter change (and while the wheels are away being tarted up)
FL22 seems to be out of stock at mx5parts though, and since I waited 5 months for an order of brake disc screws to be delivered from them, I’m a little hesitant about ordering the coolant from them!
The NC doesn’t have an expansion tank, as I understand it, just a pressurised reservoir.
There is much talk on US forums about the tank rupturing near the filler cap, and the resultant loss of coolant destroying the engine before the driver is aware (due to the fake temperature gauge).
That’s right - no separate expansion tank, it’s a pressurised header tank / reservoir.
I’ve also heard about the issue which some owners have had with cracking around the neck of the filler, causing the tank to rupture. If I was changing the coolant I’d replace the tank at the same time.
I understand there’s a shortage of FL22 at present, I also believe that, as long as the system’s flushed out to remove all of the old coolant, you can use ordinary coolant additive instead of FL22, just need to remember to change it more frequently. The reason Mazda specced FL22 I think is just due to its extended life span?
The cap is the pressure cap; any hint of damage, replace it. It is important to remember this is a pressure tank using the airspace as the expansion cushion, and it works best if filled to the correct level.
After-market metal replacements are available, and quite expensive, but cheaper then an engine rebuild. I fitted this one because it has a sight gauge at the correct level. I covered it in this mods posting
Thanks for the clarification, sounds like a fairly straight forward job once I can get some FL22. Wife’s cx3 is booked in for an (overdue) service next month so I might see what the main stealer charges for 5 litres.
Car is currently on ramps as I had a rush of blood to the head and sent off the wheels to be powder coated in a lovely candy blue colour…lol
After reading your post I ordered some Ravenol from their UK website at 8:30 tuesday morning. It arrived today. As it is concentrate and needs to be diluted with deionised or distilled water it is ideal for use after a water flush and 5 litres of concentrate will be more than enough for the NC.