2024 Nissan Z - Radiator Caps

[Landon]

Hello everyone!

Quick question about the 2024 Nissan Z radiator caps. OK, so the 2024 Nissan Z got 3 freaking radiator caps???

Which radiator cap do you open to put new radiator fluid in? Or do I need to open all 3 radiator caps and put radiator fluid to all 3 caps?

Also, on the second picture the radiator cap on the LEFT got a smaller metal male groove than the RIGHT radiator cap. Why is that, does anyone know? The LEFT radiator cap is the same cap shown on the first picture (cap #1).

In the first picture, what is the top radiator cap called on the #1 radiator cap?

 

[MCN1SMO]

#3 is the main reservoir #2 is the sub tank for the heat exchangers. Both of those tanks are pressurized thus the spring cap

You don't mess with #1 leave it be and if you swap out caps for the higher pressure ones like NISMO you only put those caps on 2 and 3. 1 is just the line for the fluid and isnt pressurized so it doesn't have the spring cap

 

[Landon]

#3 is the main reservoir #2 is the sub tank for the heat exchangers. Both of those tanks are pressurized thus the spring cap

You don't mess with #1 leave it be and if you swap out caps for the higher pressure ones like NISMO you only put those caps on 2 and 3. 1 is just the line for the fluid and isnt pressurized so it doesn't have the spring cap

I understand about cap 1.

Just to be clear on cap 2 and 3, can I put the radiator fluid in cap 2 and 3 when the level is low? So when the radiator fluid is low, put the radiator fluid on cap 2 and 3?

Or is cap 2 supposed to have a different kind of fluid to put in?

Thanks!

 

[MCN1SMO]

I understand about cap 1.

Just to be clear on cap 2 and 3, can I put the radiator fluid in cap 2 and 3 when the level is low? So when the radiator fluid is low, put the radiator fluid on cap 2 and 3?

Or is cap 2 supposed to have a different kind of fluid to put in?

Thanks!

2 and 3 use the same coolant. 3 is your main reservoir when it is being serviced. 2 is just an additional reservoir tank for the intercoolers. you can add to it but you probably wont need to. im not sure why they did 2 tanks like that on the Z.. NISMO USA had a larger capacity tank they never came out with but it was just one single tank.

 

[MCN1SMO]

this never came out but you can see the idea of how it works

disregard the nismo cap in the wrong place in their own pic lol

 

[VR30Infection]

Willing to bet that tank is split internally. I actually wouldn’t want that design. Aluminum transfers heat really well. I don’t want super hot engine coolant heating up my intercooler fluid. Also, look into “Waterwetter” by Redline. Good stuff.

 

[MCN1SMO]

Willing to bet that tank is split internally. I actually wouldn’t want that design. Aluminum transfers heat really well. I don’t want super hot engine coolant heating up my intercooler fluid. Also, look into “Waterwetter” by Redline. Good stuff.

yeah that NISMO tank I think was cancelled for whatever reason. not sure if it was the design or what? I never really saw the reason for it.

you bring up an interesting point. I wonder what the difference in temp between the fluids are between those two tanks.

 

[VR30Infection]

yeah that NISMO tank I think was cancelled for whatever reason. not sure if it was the design or what? I never really saw the reason for it.

you bring up an interesting point. I wonder what the difference in temp between the fluids are between those two tanks.

I know engine coolant temp is way hotter than you want your intercoolers. However, those reservoirs probably aren't consistently cycled into their perspective systems. I believe they are there to keep the systems full like a top off. Still, I wouldn't want it. Want intercoolers kept as cool as possible! Cooler intercoolers equal cooler charge air temps which equals more power!!

 

[C89]

#3 is the main reservoir #2 is the sub tank for the heat exchangers. Both of those tanks are pressurized thus the spring cap

You don't mess with #1 leave it be and if you swap out caps for the higher pressure ones like NISMO you only put those caps on 2 and 3. 1 is just the line for the fluid and isnt pressurized so it doesn't have the spring cap

Looking at the Nismo radiator caps, it seems like the stock cap is 137kpa and Nismo is 130kpa/0.13mpa. Does that mean performance wise, it's better to just leave it as stock?