[foghat]

Hey all,

My coolant is low. Float is about 1.25" below top threads. But no coolant light is coming on.

BMW parts department is closed till Monday, so I can't get any coolant. Was thinking of just adding distilled water. But I don't want to add so much that freezing point is significantly altered.

Does anyone know if you can just use a plain old antifreeze tester? Or will it not read properly with the bmw coolant? Was thinking as long as freezing point is high enough, could add water and check strength again. Rinse, repeat.

[crashoverride]

you cannot add too much water for what you're describing we are talking a cup or two of water in a multi-multi-gallon system. you would have to add a gallon plus to alter it negatively and even then....

[fazman]

Originally Posted by foghat

Hey all,

My coolant is low. Float is about 1.25" below top threads. But no coolant light is coming on.

BMW parts department is closed till Monday, so I can't get any coolant. Was thinking of just adding distilled water. But I don't want to add so much that freezing point is significantly altered.

Does anyone know if you can just use a plain old antifreeze tester? Or will it not read properly with the bmw coolant? Was thinking as long as freezing point is high enough, could add water and check strength again. Rinse, repeat.

Very bad idea, don't touch it especially since the low coolant light is not on yet. My coolant light came on with the bobble-thingie all the way at the bottom (It's still okay to drive to the dealer and short distances... but get the dealer to top it up ASAP). You should be fine till Monday or even a week most likely unless you have a leak?

But I would not contaminate it with off the shelf coolant or any water/distilled water. Let your SA advise you on how to check it and top it up for free for you (Top up your washer fluid while you are at it too).

[mike3000fl]

Yea leave it alone if there is no light. Just wait and buy the BMW stuff, mix it 50/50 and top up.

[fazman]

Originally Posted by mike3000fl

Yea leave it alone if there is no light. Just wait and buy the BMW stuff, mix it 50/50 and top up.

No need to buy anything, any BMW no matter how old can roll into a BMW Service bay and not even have to talk to the SA... just tell the porter that your coolant is low or your washer fluid is low and they will top it up for you for FREE. They won't even check the mileage, its done as a common courtesy. Most dealerships even have free inspection coupons on their websites.

Worst comes to worst, just go in for an oil change (with a coupon from the dealership website or a competing BMW dealership coupon for them to cross honor) and they will do the oil change for $$ and top up all fluids for free.

[MrZ]

Originally Posted by fazman

No need to buy anything, any BMW no matter how old can roll into a BMW Service bay and not even have to talk to the SA... just tell the porter that your coolant is low or your washer fluid is low and they will top it up for you for FREE.

Not all dealerships.

But I would not contaminate it with off the shelf coolant or any water/distilled water.

You do know that it's already a 50/50 mix with distilled water, right? So by adding a bit more distilled water you won't really contaminate the mix.

[mike3000fl]

Originally Posted by fazman

No need to buy anything, any BMW no matter how old can roll into a BMW Service bay and not even have to talk to the SA... just tell the porter that your coolant is low or your washer fluid is low and they will top it up for you for FREE. They won't even check the mileage, its done as a common courtesy. Most dealerships even have free inspection coupons on their websites.

Maybe if you bought it there, even then once it is out of warranty a lot of dealers aren't going to be too helpful.

No matter how old though? doubt you could drive an e21 or e30 up to the service bay and say top all the fluids up please.

[fazman]

Originally Posted by MrZ

Not all dealerships.

You do know that it's already a 50/50 mix with distilled water, right? So by adding a bit more distilled water you won't really contaminate the mix.

All the dealerships I have visited do and none have ever asked me to show anything about warranty/mileage. The guy who parks the car just tells you to pull up and tops up Washer fluid or coolant for free (Not power steering/oil/etc)

Agreed, distilled water is fine... but what about the mixture ratio? If he tops up with distilled water and no coolant, how is he to know what his mixture rate is now? If your adding 50/50 pre-mix of BMW coolant... then you know you aren't messing up the ratio compared to what it is already.

[fazman]

Originally Posted by mike3000fl

Maybe if you bought it there, even then once it is out of warranty a lot of dealers aren't going to be too helpful.

No matter how old though? doubt you could drive an e21 or e30 up to the service bay and say top all the fluids up please.

From what I was told the last time I had it topped up, "... just bring in the car and we will top it up for you, better to have us do it rather then mess it up and it's always free to have done".

[MrZ]

Originally Posted by fazman

All the dealerships I have visited do and none have ever asked me to show anything about warranty/mileage. The guy who parks the car just tells you to pull up and tops up Washer fluid or coolant for free (Not power steering/oil/etc)

Agreed, distilled water is fine... but what about the mixture ratio? If he tops up with distilled water and no coolant, how is he to know what his mixture rate is now? If your adding 50/50 pre-mix of BMW coolant... then you know you aren't messing up the ratio compared to what it is already.

I guess really depends on the dealer and the country. I had oil topped up for free and I've had times when I had to pay for top ups.
One of the dealerships I've been to even came up with a "top up charge". If your car is in for service they pretty much charge you a flat fee (like $7) and say they top up all the fluids (coolant/oil/windshield washer/PS fluid).

Correct me if I'm wrong, but the coolant sold at dealers is full strength (not pre-mixed) and you have to mix it yourself. Well, at least I haven't seen pre-mixed coolant at Canadian dealerships.

And if the car needs a slight top up (i.e. 100ml), the ratio change is very small (if it was a perfect 50:50 it'll change to 50.6:49.4, at 8l capacity).

[fazman]

Originally Posted by MrZ

I guess really depends on the dealer and the country. I had oil topped up for free and I've had times when I had to pay for top ups.
One of the dealerships I've been to even came up with a "top up charge". If your car is in for service they pretty much charge you a flat fee (like $7) and say they top up all the fluids (coolant/oil/windshield washer/PS fluid).

Correct me if I'm wrong, but the coolant sold at dealers is full strength (not pre-mixed) and you have to mix it yourself. Well, at least I haven't seen pre-mixed coolant at Canadian dealerships.

And if the car needs a slight top up (i.e. 100ml), the ratio change is very small (if it was a perfect 50:50 it'll change to 50.6:49.4, at 8l capacity).

I guess it is different from location/dealerships, mine brings out a large jug of pre mixed coolant and tops me up. Washer fluid is from a hose they pull down the ceiling. Never had to top up oil, but i saw a 6 series need it and they brought out a different large jug and funnel for that owner.

[roadkillrob]

If it is that low and isn't leaking it probably means it has evaporated which means it is actually more concentrated than 50/50 as the water is all that evaporates and adding distilled water would be fine to top it up (especially since it is summer), then you would want to use a normal coolant measuring device to check the freezing boiling point if you were going to leave it like that. My guess is, that if that much has evaporated, then you are still on original coolant and you indicate you are driving a 2008 135i, so 5 years is time to change it anyway!

[Efthreeoh]

Originally Posted by roadkillrob

If it is that low and isn't leaking it probably means it has evaporated which means it is actually more concentrated than 50/50 as the water is all that evaporates and adding distilled water would be fine to top it up (especially since it is summer), then you would want to use a normal coolant measuring device to check the freezing boiling point if you were going to leave it like that. My guess is, that if that much has evaporated, then you are still on original coolant and you indicate you are driving a 2008 135i, so 5 years is time to change it anyway!

This is chemically impossible. The water in the coolant in chemically bonded to the ethylene molecules and does not separate from the ethylene glycol and evaporate by itself. Water is added to ethylene glycol in antifreeze to improve the ethylene glycol's ability to conduct heat. Ethylene glycol is also used as a desiccant (i.e. it absorbs water).

[PichaDis11]

Distilled is a go to top up. even tho you said it is an 1' below it wouldnt take tht much fluid to bring it to normal levels. More importantly tho you should check for leaks around the system.

[foghat]

I ended up putting in about a liter of distilled water. I did a strength test before hand and it was reading good to -45C.

[Surly73]

Originally Posted by foghat

Hey all,

My coolant is low. Float is about 1.25" below top threads. But no coolant light is coming on.

BMW parts department is closed till Monday, so I can't get any coolant. Was thinking of just adding distilled water. But I don't want to add so much that freezing point is significantly altered.

Does anyone know if you can just use a plain old antifreeze tester? Or will it not read properly with the bmw coolant? Was thinking as long as freezing point is high enough, could add water and check strength again. Rinse, repeat.

BMWs are just cars. I don't know why so many people believe everything about the car is so special that you need special everything in order to take care of it.

BMW OE coolant is G-48, which has different properties than average off-the-shelf green stuff, but it's not the BMW logo that makes it special. Any old coolant tester will help test the strength and standard test strips will help you check the pH. This stuff is cheap enough that anyone with any DIY inclinations should have them.

Originally Posted by crashoverride

you cannot add too much water for what you're describing we are talking a cup or two of water in a multi-multi-gallon system. you would have to add a gallon plus to alter it negatively and even then....

Agree completely, assuming that you're already close to 50/50 concentration and you don't have a major leak for which you repeatedly top up.

Originally Posted by fazman

Very bad idea, don't touch it especially since the low coolant light is not on yet. My coolant light came on with the bobble-thingie all the way at the bottom (It's still okay to drive to the dealer and short distances... but get the dealer to top it up ASAP). You should be fine till Monday or even a week most likely unless you have a leak?

But I would not contaminate it with off the shelf coolant or any water/distilled water. Let your SA advise you on how to check it and top it up for free for you (Top up your washer fluid while you are at it too).

Now come on... This is not dealer worthy at all, nor is it "ASAP", nor do you need advise from an SA on how to deal with it (yet). (Unless the car in question is nearly new or you like hanging around at your dealer).

OP: feel free to top up with distilled water for now. Check the strength as indicated above, change coolant every 2 years (3 max), and if you find yourself low again then you'll have to go find the leak. It's not normal to lose any coolant on an E90 and repeated top ups with distilled water will start to affect the concentration.

What you should NOT do is try to make a 50/50 mix of anything other than BMW OE coolant and mix it in with what you have in there already. Compatibility is not guaranteed and then you could start to get yourself in some trouble.