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Anyone know why the top of the radiator would be leaking distilled water when I fill it?
Thanks
Chad
Where did you add just distilled water to the system? Distilled water (0.997 kg/L) is lighter in density than a coolant/water blend (1.07 kg/L) so if you added distilled water straight it might not fully blend and would immediately travel up (akin to making a black and tan beer with lager and a stout).
Last edited by wannawankel; 01-02-2024 at 07:53 AM.
Reason: I like editing
Nice. Yeah, it's smoking from the radiator. I think that's why. Any idea how much coolant goes through the system? I put about 2 gallons in it, the coolant light is on, and the coolant bottle is empty. I did use distilled water (4 gallons), per the diy write up. Is that wrong?
(I see you're in Wilmington, MA - where I work. I live in Metro West Boston).
Normally all RX-8's use premixed Mazda FL-22 and that's the only type I've used in the car. I've never added just distilled water and with ~ 60K on the odo I've done two coolant replacements that included the engine block drain. I was also told to change the coolant and replace with fresh coolant on a slope with the engine (front) at the highest point (for the latter burping procedure).
The coolant takes 10.0L from the S2 manual (below) but needs to have a warm up engine on period to ensure the system gets "burped". See that coolant level procedure below the diagram
Engine coolant capacity (approx. quantity)
MT: 10.0 L {10.6 US qt, 8.80 Imp qt}
AT: 9.8 L {10 US qt, 8.6 Imp qt}
7. Refill the engine coolant into the coolant reserve tank up to the F mark.
8. Install the cooling system cap.
CAUTION:
If the water temperature gauge rises too high, stop the engine and decrease
the engine coolant temperature to prevent overheating. Then, verify the
malfunctioning part and repair or replace it.
9. Start the engine and warm up the engine by idling.
10. After the engine warms up, perform the following steps. At this time, be careful of the
engine coolant temperature to prevent overheating.
a. Run the engine at approx. 2,500 rpm for 5 min.
b. Run the engine at approx. 3,000 rpm for5 s, then return to idling.
c. Repeat step (2) several times.
11. Stop the engine, and inspect the engine coolant
Last edited by wannawankel; 01-02-2024 at 11:17 AM.
Reason: I like editing
Water by itself in the RX-8 will have local boiling issues (and local boiling leads to steam generation that leads to nearly zero heat transfer at that spot). If your cap isn't holding pressure the boiling point decreases as the pressure decreases to atmospheric pressure. I did write up something a while back on why it's important to get the coolant type, %, and pressure right to prevent overheating - below:
Hi everyone. I didn't see any smoke, but the engine temperature is going to the top after 15 minutes of driving. Any thoughts. This is what it was doing with smoke before the coolant change. Is it the atmosphere?
Not sure what it could be. When I fill the coolant bottle the coolant comes right out of the radiator. The coolant light is on and the coolant bottle is empty. I have read.
It's time to upgrade to an all alloy radiator. There are a few good brands around that should drop straight in. Most peeps that have had 8s for a while have already done this at some point. The plastic factory head and foot tanks break down due to heat and age. This is when the pipes bteak off and you are stranded. Dont bother trying to repair it. Your 8 will thank you for going alloy rad.
I just installed a new radiator, and the engine temperature is fine now. Furthermore, it is holding coolant, which it wasn't. But, the radiator is smoking and the fan is not running. Should the fan be running? When does it kick on?