Did my annual oil change, 2016 F Type R, and as I regularly do I check the coolant level. It seemed just a smidge above minimum, so I add coolant. I did not dilute the coolant. I filled it up to the max line. I drove minimally-like 15 miles and washed it the following day. It appears the coolant is down again which has me concerned it is time to swap the coolant pipes and possible water pump. The car has 27400 on the clock but again a 2016. A couple questions-can I add distilled to dilute the coolant or does the coolant need to be full strength in the expansion tank? In the past, I just put it is full strength because it was minimal I was adding. I think it is safe to dilute 50/50 but want to confirm. Also, any other things suggested if I move forward with the coolant pipes and water pump?

 

Ideally you should add coolant of the right concentration. Some bottles come concentrated and you need to mix with distilled water. Others are already premixed. Do what it says on the bottle. If it's just a small amount it won't make a material difference but over time you could end up too concentrated or too dilute

You need to find the source of the leak before you throw parts at it. There are literally dozens and dozens of joints, connectors, seals etc on the system. Without that you are just guessing

A good shop can do a high pressure test to track it down. Then repair where it's leaking. At the same time if you want to replace additional plastic pipes while it's being opened up anyway that's a good idea. But I would find out what's leaking first

And - don't drive low on coolant. Alu engine blocks are sensitive to overheating and you can warp / destroy them in 30s

Oil level ok? No contamination in oil? Any white smoke from exhaust?

 

It has been IMO leaking a bit for some time. The expansion tank was replaced under warranty but still always smelled coolant. Anyway the Jaguar Antifreeze JLM209722 isn't real clear. It states what it contains and I clearly see nothing about distilled water but yet states boiling point 50% mixture is 226 degrees. So I would presume this is straight coolant.

 

The water pump is prone to weep, IME based on my previous 5.0 XKR. The coolant mix is 50/50 which protects down to -40C degrees according to my handbook.

 

You can always check the level of protection of whatever is in the container and also what is in the car's reservoir.

I bought one of these refractometers after wasting time with the floaters in the tube form factor.


Once you calibrate this refractometer, you can easily test the protection level of your coolant as well as the other suggested fluids.

 

Here is a really good video on how to tell if your coolant is still good. Several test methods of different coolant aspects.