[watchout-everyone]

Hello,

I am curious if a car (mine is 2011 BMW 328i) can be without a coolant for a long time. The car will not be driven and it will be completely idle at home while I try to get some DIY done (valve cover, ofhg, coolant hoses, and coolant itself is actually very dirty).

With that being said, while I will try to do it DIY, i have limited time and transportation (in case i need to drop by Walmart for needed tools) so it might take 2 ~ 3 days for me to complete them as newbie.

So my questions are
1. Can a car (which will be at home and not driven at all) be without coolant for few days (probably up-to a week)?

2. Could you please recommend a great coolant system cleaner for my BMW? The coolant is very filthy dirty (it's like brown when i looked into it.... I am replacing all the hoes) and i was told it will need to do flushing with 'coolant system cleaner' and likely several time. (Right now, i am thinking this one Radiator Cleaner by Prestone)

Any help would be greatly appreciated.

[eljay]

You will be fine leaving it empty for a few days. Coolant has a slick coating that will still be around the block etc., so you won't do any damage with leaving it empty.

For a flush, yes, the Prestone cleaner will work, but you can also just refill it with distilled water, do a bleeding procedure with the pump, run it to circulate, drain and repeat a couple of times and then refill it with proper coolant mixture.

[eljay]

Also, depending on your mileage, I would also add water pump and thermostat and the "mickey mouse" hose in the front to your to-do list since you are replacing coolant hoses and coolant will be drained.

[watchout-everyone]

Originally Posted by eljay

Also, depending on your mileage, I would also add water pump and thermostat and the "mickey mouse" hose in the front to your to-do list since you are replacing coolant hoses and coolant will be drained.

Thank you! Previous owner told me he changed water pump and thermostat just last year so i planned to just change that mickey mouse hose (i believe that's this one https://www.fcpeuro.com/products/bmw...in-11537545890)

[crashoverride]

take a hard look at the hoses they are very prone to failure. Crazy expensive if bought at dealership when one fails better than half the price when ordered online in advance.

Your idea of a long time empty scares me a bit there are all sorts of nooks and crannies that will retain water and moisture. While antifreeze has anti corrosion properties if left to dry out those surfaces are prone to rust. As any residual coating will quickly dissipate

[mct128i]

Originally Posted by watchout-everyone

Thank you! Previous owner told me he changed water pump and thermostat just last year so i planned to just change that mickey mouse hose (i believe that's this one https://www.fcpeuro.com/products/bmw...in-11537545890)

If these were changed just last year then I would be concerned to know why the coolant is now so filthy. Is the coolant contaminated with oil perhaps? This can happen when the OFHG deteriorates and allows oil and coolant to mix...

[watchout-everyone]

Originally Posted by crashoverride

take a hard look at the hoses they are very prone to failure. Crazy expensive if bought at dealership when one fails better than half the price when ordered online in advance.

Your idea of a long time empty scares me a bit there are all sorts of nooks and crannies that will retain water and moisture. While antifreeze has anti corrosion properties if left to dry out those surfaces are prone to rust. As any residual coating will quickly dissipate

Thank you for your confirmation. I will leave them in for now and plan my schedule accordingly

[whyzee125]

I'd just fill it with water just in case, that way you can start it up after each job to make sure you did it right and that will help to flush out any rust/crust too as that circulates.

[watchout-everyone]

Originally Posted by mct128i

If these were changed just last year then I would be concerned to know why the coolant is now so filthy. Is the coolant contaminated with oil perhaps? This can happen when the OFHG deteriorates and allows oil and coolant to mix...

Yes, that's correct. I will be looking to fix OFHG and also VGC.

There are a lot of leaks and my original intention was to drain all coolant while I spent few days to fix OFHG, VGC, coolant hose, and few other mounts stuff.

I think it will be emptied for maybe 3 days but it might be a week (if i need to order something from FCPEuro)

[TheMidnightNarwhal]

If it were my car, I would not worry about no coolant for 3 days or a week tbh. Unless the car is dunked in salt water I don't think rust will happen that fast.

[watchout-everyone]

Originally Posted by TheMidnightNarwhal

If it were my car, I would not worry about no coolant for 3 days or a week tbh. Unless the car is dunked in salt water I don't think rust will happen that fast.

Thank you. The reason why I am asking about leaving the coolant empty is because i can't really start the car right now (because of lack of oil and oil pan situation).

Can I drain the coolant and re-fill it with water (or even fresh BMW coolant) and just leave it in there without starting the engine to prevent rust? I thought about this but was unsure because, since the car won't be running, the new coolant/water won't circulate on its own.

[TheMidnightNarwhal]

Originally Posted by watchout-everyone

Thank you. The reason why I am asking about leaving the coolant empty is because i can't really start the car right now (because of lack of oil and oil pan situation).

Can I drain the coolant and re-fill it with water (or even fresh BMW coolant) and just leave it in there without starting the engine to prevent rust? I thought about this but was unsure because, since the car won't be running, the new coolant/water won't circulate on its own.

These cars have electric water pump so you don't need to run the engine to bleed and circulate. While you fill the car, make sure the bleeder screw is removed from expansion tank. Fill it up until it doesn't take anymore. Close bleeder screw, close expansion tank cap. Go in the car, turn the car to ON (don't start it though), put the climate into manual mode, put the temperature to the highest hot, put the fan to the lowest setting, press the gas pedal to the floor for ~ 10 seconds. You should hear the water pump run and it will do it's thing for about 10 minutes. After that, check the level and if it needs more coolant, repeat.

[watchout-everyone]

Originally Posted by TheMidnightNarwhal

These cars have electric water pump so you don't need to run the engine to bleed and circulate. While you fill the car, make sure the bleeder screw is removed from expansion tank. Fill it up until it doesn't take anymore. Close bleeder screw, close expansion tank cap. Go in the car, turn the car to ON (don't start it though), put the climate into manual mode, put the temperature to the highest hot, put the fan to the lowest setting, press the gas pedal to the floor for ~ 10 seconds. You should hear the water pump run and it will do it's thing for about 10 minutes. After that, check the level and if it needs more coolant, repeat.

Ok that's great to hear and had no clue that was even a thing.

[mainbearing]

BTW, the electric water pump should not be allow to dry out. I think that was either in the Bentley manual or the Pierburg water pump instruction sheet.

I would prefer to finish work on the cooling system on the same day. Make sure you flush out all that cleaning chemical out of the system.

If you are changing all the coolant hoses and Mickey flange, then do the coolant tank and cap as well. The tank rots from the inside out too.

[watchout-everyone]

Originally Posted by mainbearing

BTW, the electric water pump should not be allow to dry out. I think that was either in the Bentley manual or the Pierburg water pump instruction sheet.

I would prefer to finish work on the cooling system on the same day. Make sure you flush out all that cleaning chemical out of the system.

If you are changing all the coolant hoses and Mickey flange, then do the coolant tank and cap as well. The tank rots from the inside out too.

Thank you for response!

For the coolant tank, can I take it out and dump it in a hot water or something to clean it instead of buying a new one? After that, I also planned to use a 'coolant system cleaner' to further clean my car because I saw it was dirty inside (Inside the tank and also the coolant were brown due to heavy oil leaks from VGC and OFGH which I am also changing).

After reading your comment, I will be putting some fresh coolant back into the tank for now. I emptied a little bit earlier by using a pumper into the coolant tank (following this guide

) but I realized I don't have a E-10 socket for me to take out the OFHG (I ordered and it's coming in tomorrow).

Once I take out the OFHG, I plan to install a new battery and run what MidnightNarwhal suggested.

[Bims328i]

Take a few sandwich bags along with a handful of rubber bands and seal all the coolant lines for extra precaution while it sits.

Be careful when you're installing that bolt under the intake of OFHG, it comes off easier than it goes on for some reason. Pay close attention the socket is straight when applying torque.

I can attest to the coolant tank as well since I did my water pump a while back and eventually my expansion tank sprang a leak all along the joining seam.

[watchout-everyone]

Originally Posted by mainbearing

BTW, the electric water pump should not be allow to dry out. I think that was either in the Bentley manual or the Pierburg water pump instruction sheet.

I would prefer to finish work on the cooling system on the same day. Make sure you flush out all that cleaning chemical out of the system.

If you are changing all the coolant hoses and Mickey flange, then do the coolant tank and cap as well. The tank rots from the inside out too.

Originally Posted by Bims328i

Take a few sandwich bags along with a handful of rubber bands and seal all the coolant lines for extra precaution while it sits.

Be careful when you're installing that bolt under the intake of OFHG, it comes off easier than it goes on for some reason. Pay close attention the socket is straight when applying torque.

I can attest to the coolant tank as well since I did my water pump a while back and eventually my expansion tank sprang a leak all along the joining seam.

Thank you!

When you mentioned about putting bags to the coolant lines, I am assuming when I actually take out the Engine Oil Filter Housing

[eljay]

Yes, you can plug the lines if you are worried about it drying out.

I think you'd be fine without it.

Think about all the engines being sold by salvage yards and when they are stored for months they typically don't have fluids and they are fine. If they were blowing up as a result, no one would be buying them and no one would be selling them either.