Coolant level check.

[Phmode]

Out for a bimble yesterday and it was hot, hot, hot. And so was I. And so was the bike.

Now the rad needs to be cleaned and the beast needs its 18k service so lots of coolant is going to go down the drain one way or another. But when I got home I thought I should check the coolant level anyway. And herein lies the problem I have always had with both the 13 and the 12 before it; I have never been able to see the coolant level in the so-called clear plastic header tank. Not that it is a header tank in a vacuum-filled system but you get my drift.

I spent many happy hours with the 12 shining torches and dipping dippy things but to no avail. There was simply no way to 'see' the level. I decided that if I could see coolant inside the tank with the cap off then that was good enough, put the cap back on and forgot all about it till the radiator blew itself apart within a thousand miles.

And so, there was I on hands and knees yesterday in the sweltering sun trying to see the damn level again. Nope, no way.

I wondered if there was anything in the Rider's Manual showing how to 'actually' see the level.

Well, there's a turn up for the book, both the K13 and the K12 books in fact. There is absolutely nothing in there about coolant level, neither how to check it nor how to top it up. Nothing in fact about ever needing to check it.

It says 'If the high coolant level light comes on take it to the nearest dealer and have the fault rectified', but nothing about making sure the bloody thing has coolant in there before you say 'Bring My Wallet' and hand it over to the dealer?

Even after 12 years of K ownership I still find this omission quite shocking on the part of BMW.

So, if you can see the level through your tank, when peering into the bowels of the tank where is your level when it is between Min and Max markings on the tank? Inside, there is a sort of rectangular chamber with a nozzle poking up, so is your level above or below that nozzle...I can't believe I'm actually having to ask this.

[farmer]

yeah, just had a read of the manual, couple of tips for high coolant temperature, nothing else..nothing.
reminds me of when i first wanted to check my oil level..... it was much to stupid to ask anyone and took about a week before i found the oil level guess pipe.

[Capt Howdy]

There is a description on checking the coolant level in the expansion tank on the LHS of the bike. This is in the reProm dvd I’m away from my computer at the moment but will post details shortly

[Capt Howdy]

On the rear of the expansion tank in front of the power socket there are max and min marks for the coolant level.

[Phmode]

Yes, thanks for that.

As you will have read in my original moany post, the min and max marks are not the problem, they are where they have always been and even I can see them.

As I said, it is the level that is totally invisible. I can see the level inside the tank but there is no indication inside as to whether it is right or wrong.

What I can't do is see the level 'through' the translucent plastic to compare it to the min and max marks.

[richtea]

You need something that floats, with markers. Like a small polystyrene ball jabbed with a lolly stick.
Test in a glass first to see how low it sinks. Then pop it into the expansion tank, note the first marker visible, fetch it out and compare.

A nano-version of this:
https://powerandwater.com.au/product/dipstick-water-tank/

[Capt Howdy]

Ok again I am awAy from my computer but there is a specified way to check the level by taking off the expansion tank cap and looking inside. Will post later

[Capt Howdy]

The early models did not have the ‘min-max’ marks on the expansion tank. To get the correct level you have to fill to the bottom edge of the expansion tank filler neck and then draw off 200ml.

[black-k1]

Given the expansion tank is just a resevoir for the coolant to expand into and draw from as it cools and contracts, and that it has a vent to the outside, why would it matter if it's over filled? The worst that will happen is it'll spit some excess coolant out the vent.

Fill it until you're sure, by looking down the neck of the filler to the coolant level, that it's at or past MAX, put the lid on and leave it.

[Capt Howdy]

 I agree with that however I’m just making known the recommended practice. Also avoiding coolant getting onto the rear tyre.

[Phmode]

You need something that floats, with markers. Like a small polystyrene ball jabbed with a lolly stick.
Test in a glass first to see how low it sinks. Then pop it into the expansion tank, note the first marker visible, fetch it out and compare.

A nano-version of this:
https://powerandwater.com.au/product/dipstick-water-tank/

The problem with this and other 'dipstick-related' methods is that there a bunch of 'plastic moulded stuff' inside the reservoir, which may indeed be part of the mechanism by which the fluid is ingested and degested (and that isn't even a real word, probably should be regurgitated) into and out of the cooling system as it heats and cools.