Question on checking engine coolant level, C7
 

In the owners manual there is a reference to the cold fill line on the coolant surge tank.
Is this on the outside or inside of tank?
I don't see a line on the outside.
Removing the cap there is a white, plastic looking piece that looks like it could serve as a level indicator.
Looked on you tube for a video, found none.
Thanks!

I don't know for sure if this is it or not but look at the bottom front front of the reservoir between the electrical center and the reservoir. My reservoir has a black top with a white body. Right at the bottom of the white body there is a raised white line with two raised white arrows pointing down at it and some sort of symbol between the two arrows. I believe that line is the cold fill line. You may need a pencil style flash light that you can put beside the electrical center aimed at the reservoir to get enough light to see it.

For some reason over the last few decades designers of many consumer products seem to think the human eye can easily discern white on white letters, black on black, blue on blue, etc. It must be something they teach in school, How to make things hard when you don't have to. The brake reservoir on the master cylinder is the same way. Totally invisible to the casual observer but visible if you use a light to generate some shadows to get contrast.

Bill

Thanks,
I was able to locate the white line. Not easy to see without a pencil light.
Ron

there is only 1 level indicator right? (min level) and it doesn't say max or min. with couple arrows and "read manual" symbol I guess in the middle.

Very hard to see, so how about max level? no worries for max?

brake fluid I can't see it at all, can't see where the fluid level is even with a flash light.

also for my windshield fluid, there seems to be cut aways or ripped off. (in the center of pic) do you guys' also look like that? odd why is it like that.

that just looks like remnants from the plastic manufacturing. Just visual.

Only minimal level and no max level on the surge tank right? How often do you guys top off the tank? My coolant gets below the level often, probably because I drive in city traffic a lot.

So any dex-cool will do? There are a few brands. And mix it to 60% drinkable water/distilled water and 40% dex-cool. Last time when coolant was low I filled it up with 9oz of distilled water. So this time I better do coolant and not water only again. This one will do right, cheapest I found. https://www.walmart.com/ip/Prestone-...-1gal/16889200

Do you guys just fill it to the cold line, or do you go over it some? I think I have been driving it below the mark, not too long though the temp was ok.

There is a low level indicator on the tank. It is clear like the tank but it has raised lettering and an arrow. Its right at the bottom of the tank where it curves down word and in the front facing the fuse box

The line outside is hard to see but that plastic rib inside is perfectly aligned with it. Just fill to the top of that little rib.

Should not be losing coolant. It would probably be a radiator cap not sealing, hose(s) clamp not tight, overflow tank cap allowing fluid to escape under pressure. Worst case:ack:, check your oil for water contamination from coolant getting past head gaskets or such & getting into engine. I researched this losing of coolant before chiming in with my OPINION.:thumbs:

It's not a low level or max level. It's a fill-to mark.

Cold fill-to mark right? So there is no low level so when do you know when to fill it when it gets low? just keep checking and fill it to the fill-to mark?

Also in the manual there is no part number for the coolant, it just says dex-cool, so any dex-cool coolant will do?

Yes, according to my OM for '16 Z, that is COLD fill mark. It may be higher when hot so don't check when hot 'cause you could get STEAMED:D. It just calls for Dex-Cool so any will do & it should be a 40% Dex-Cool/60% drinking water (according to OM). Most people here recommend distilled water 'cause you never know what minerals/contaminants are in the drinking water which you don't want in the system. Capacity is 11.8 qts. for LT1/LT4. Also found Service Bulletin PIP5330B on corvetteactioncenter.com for '16-'17 all Vettes about loss of coolant or smell of coolant. It says dealer should pressure check system & if leaks are found at outer cylinder head bolts then that/those banks need replaced-OH JOY!

Oh god that doesn't sound good. So you guys don't really lose coolant? My other car would lose coolant I thought it's normal if it's very little.

I googled PIP5330B and got results but searched for it in forum here and I didn't find any beside this thread, interesting I guess few people have this problem or few discovered it.

So PIP5330B sounds like a big job, Sounds like Z might be staying at the dealer for awhile :(

I would not buy the premixed 50/50 Dex Cool. It's going to take almost 3 gal. of those to REFILL if you flush the system. You are paying for WATER in the premix stuff & it's mixed higher than the OM calls for, whereas the CONCENTRATE you add the water, so you're paying just for Dex Cool (less,1 gal. makes 2 gals @ 50%).

So I can't seem to see (older eyes maybe) if coolant is up to the line when looking from the outside of the tank. I can see a line but its not obvious if coolant is up to that line. Maybe its because its not? When I remove the cap (cold) I can see some coolant but it is at the very bottom of what I can see. Might it be low?

For context I just had my local dealer change my coolant and was verifying that they refilled it to the correct level.

First, not my business but what year & mileage is your car? Coolant is to be changed @ 5 yrs or 150,000 miles whichever comes first. I just looked at my coolant tank & Damn it is in a tough spot to check. Wait till it is completely cool & try shining a light into the INSIDE of tank. You should be able to see the hot/cold lines easier & it should be at “cold” line. Mix is 40% Dex-Cool & 60% clean drinkable water.👍

Yeah I always had difficulty checking the level as well! Yeah try shining a flash light inside the tank and check the level outside, that should help some. I don't believe there is a max line only cold fill line.

Before it was about 1/3 inch below the line, I filled it up with distilled water only, now it's 1/3 to 1/2 inch below the cold line again, I live in Vegas so should 100% distilled water be ok or I need to do what manual says?

So I know the coolant level should be checked when the engine is cold. However what SHOULD the level be when at normal operating temperature. Dumb question but please read on.

The reason why I ask is as follows. I recently had my coolant changed by my local dealer. Now I can see coolant in the under-the-hood tank but it is below the fill line. When I go to the dealer and ask them to fill it up properly the engine may still be warm if they jump right on it. So can I tell when warm if the right level is in the system? Presumably higher than the cold fill line??

If you see coolant in the tank when cool it’s good. I think you’re splitting hairs, it’s not enough to worry about. 👍

One only loses coolant if it goes somewhere other than staying in the coolant system. I know that sounds obvious, but true. Hence, if one needs to top off the system it is either leaking somewhere or being forced out the overflow from either a faulty pressure cap and/or overheating. Just saying... :yesnod: