Rocket 3 Roadster Possibly Overheating?

Distilled or deionised water is fine to top up with. Typically 50% of what goes into the coolant system is that anyway.

just checked and it is good to about 35 degrees fahrenheit
lol lol

So…it is ok to put distilled water in my radiator for now? Is what I’m gathering lol Since I have coolant in the radiator already and I’m just trying to tap it off and get out any air from the bleed bolt, I’m good to go then.

So, I’m just waiting for my new radiator cap.

Yeap that's it.

And while we're at it. If ever in doubt about what coolant to top up with, just use deioniseded/distilled/demineralised water. It's cheaper and compatibility with all coolant (except expensive waterless coolant...).
Of course any significant top up will need the right coolant to keep the mixture somewhat right.
But the water will get you out of a jam and you can get it in any auto shop and even supermarkets in the car care bits section.

I wasn’t able to find the the caps you mentioned @atomsplitter , but I believe I found a near exact replacement for the Rad Cap. I was wondering if this is acceptable but most of all, safe.

Here’s the product link:


It’s probably overkill but I did buy the proper OEM, it just won’t be here for a while, and if this rad cap is good for my rocket, at least I have a spare part.

buddazero said:

So…it is ok to put distilled water in my radiator for now? Is what I’m gathering lol Since I have coolant in the radiator already and I’m just trying to tap it off and get out any air from the bleed bolt, I’m good to go then.

So, I’m just waiting for my new radiator cap.

Click to expand...

Yes, top up and seal up and you're golden.

A bit of understanding of your cooling system might help here. Water is the actual coolant because it has a very high specific heat capacity (symbol cp). If you raise the temperature of water to 212F it achieves 'saturation' meaning it can't hold any more heat without going thru a phase change. The amount of heat to change one pound mass water to one pound mass of steam at 212F (at atmospheric pressure) is 970 BTUs. That's a lot of BTUs (a BTU is defined as the amount of heat required to raise the temperature of one pound mass of water by one degree Fahrenheit at about 60°F). It's called the "latent heat of vaporization" and it's how the heat in your engine is moved from where it's produced in the combustion chamber to atmosphere flowing across the cooling fins of your radiator. Once water at atmospheric pressure reaches saturation adding heat will NOT raise its temperature, only vaporize the mass faster. One gallon of water has 8.34 pounds-mass so if your cooling system holds a gallon of water, it has the potential to hold 8090 BTUs circulating in the system. As you raise pressure on the water the BTUs it will hold goes UP before boiling occurs. That's why the cooling system of your motorcycle has a pressure relief cap to increase the total BTUs the system can remove effectively from the combustion process to atmosphere. To understand how your system was designed you need to know the heat load and how much has to be removed to maintain material properties desired (too much heat expands metal beyond operational limits). You can arrive at that heat value by calculating the total heat of the fuel burned per hour at full throttle for the maximum heat load. The cooling system can then be designed to remove that heat load plus an added safety margin of say 20%. To calculate the size of the heat exchanger needed (radiator) the engineers use that heat load value and how much air differential temperature is needed. That leads to how much water flow is needed to move those BTUs so the result is: Rate of Heat is equal to the mass flow rate times the differential temperature of the source to heat sink. Knowing that then gives you a pump flow rate required to maintain the system below the limits. The pump flow has to be calculated based on variable speeds since the engine has a rev range. After doing all the calculations the system is designed to handle the heat loads expected under all conditions.

buddazero said:

I wasn’t able to find the the caps you mentioned @atomsplitter , but I believe I found a near exact replacement for the Rad Cap. I was wondering if this is acceptable but most of all, safe.

Here’s the product link:

https://www.autozone.com/p/duralast-radiator-cap-7516/9596?searchText=Coolant+cap&productPartGroupId=azpg1492&productBrandId=CFHH&productUniqueId=3937581257

It’s probably overkill but I did buy the proper OEM, it just won’t be here for a while, and if this rad cap is good for my rocket, at least I have a spare part.

Click to expand...

It says it's vented so should be good to go as long as it seals the system.

atomsplitter said:

It says it's vented so should be good to go as long as it seals the system.

Click to expand...

Most rad caps are vented, no?

buddazero said:

Most rad caps are vented, no?

Click to expand...

Yup, but not all.