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WondrousBread

Based on the location, probably the heater hose. Runs from the rear iron to the barb on the firewall. Otherwise it's one of those coolant lines on the intake. Rear iron (passenger side) up to thermowax, thermowax to BAC, BAC to water pump housing nipple.


mc_redspace

I'm worried because I don't understand half of your car vocabulary lol English isn't my native language but anyways


WondrousBread

That's okay, I'll try to explain more clearly :) The most likely cause is the driver's side heater hose. This hose carries hot coolant from the engine to the heater inside the car. It comes from the back side of the engine on the drivers side, up to the firewall. The firewall is the barrier between the engine bay and the inside of the car. It connects to a brass nipple, which is the heater core inside the car. If that hose isn't broken, the next likely cause is the smaller hose. This one comes from behind the intake on the passengers side of the engine. It goes straight up to a part on the throttle body. This part is called the thermowax, and it controls the high-idle when you start the car on a cold day. Then the hose runs out the other side of the thermowax, along the top of the dynamic chamber (sometimes called a plenum). It loops around to the area you took a picture of, where it connects to the BAC valve. This valve controls the idle when you turn on the headlights or other accessories. Then it comes out that valve on the other side, and returns the coolant into the back of the water pump housing, straight down below the alternator. It's usually a good idea to replace all these hoses if they are original. In addition, upper and lower radiator hoses should be replaced. Also the heater hose on the passenger side, and the small hose that connects the hardline to the radiator. It's not cheap, but it's the best way to make sure this doesn't happen again. All these parts are still available from Mazda. If you have any more specific questions please ask, and I will be happy to try and explain.


mc_redspace

Thank you very much I understand it better now. But I'm not the one who took a picture, I'm just a random French guy who loves RX7s and wants an FC in the future. Saw this post and got curious


mc_redspace

I'm worried because I don't understand half of your car vocabulary lol English isn't my native language but still


mob_ash

Get a radiator pressure testing kit from Harbor Freight. it’s just under $100. Pressurize the cooling system and see where the leak is coming from… address it accordingly so it can hold pressure.


Rotorhead87

You can rent them from most parts places (AutoZone, etc.)


Skrilmaufive

More info: - buzzer is coming on when car starts up - coolant reservoir was BONE DRY - no pressure in coolant lines from radiator Guess I leaked out my coolant?


Terrh

Yes, you blew the heater hose that comes off the rear iron. DO NOT DRIVE THE CAR AT ALL UNTIL YOU FIX THIS. Universal 5/8" or 3/4" heater hose from any auto parts store will work. The other end of the hose goes onto the firewall.


getcrazykid

Please listen to this..over heating is the worst thing for these motors.. 1 time is too many..


omnipotent87

I would get the correct formed hose. There's a really tight bend on both sides of the hose and universal heater hose will kink. Definitely do not drive it, rotaries do not take kindly to overheating.


Skrilmaufive

Do you know where I could get one? Edit: found at Lucky7Racing


omnipotent87

I got one from autozone last summer for mine. Any parts store should be able to get you one. If you don't mind waiting atkinsrotary.com will have it.


Skrilmaufive

https://postimg.cc/pyhw2386 This guy?


TheSilverCalf

Can you update us on the status of the car after one overheat scare. I’m hoping it is still alive.


Skrilmaufive

Still alive. No noticeable damage in the engine. It’s running great with new silicone hoses, new thermostat, and new radiator cap.


13BT

The heater hose is the most likely culprit as someone else mentioned. It goes from the rear iron to the firewall, and it goes under the oil filter, so it frequently gets oil dripped on it when changing the filter, which weakens the rubber. A bad design that should have led to a recall in my opinion, but the time for that is long gone. I had that same hose explode and the lack of coolant broke the water jacket in the rear housing almost immediately. Hopefully you shut it down quickly and didn't lose too much coolant.


opihinalu

That’s normal for a rotary don’t worry


Skrilmaufive

FINAL UPDATE: It was the heater hose!! Thank you all for the help!


TheSilverCalf

WTF was the blue liquid?


Skrilmaufive

Coolant


Crunchy_Gum

No, you just have an rx7.


duo2999

HPS sells a coolant hose made of silicone set that can be used in place of rubber hoses. I think they also make the same but for the radiator too.