Coolant reservoir

Discussion in 'Parallel Universe' started by BMWHillbilly, Jun 4, 2010.

  1. BMWHillbilly

    BMWHillbilly Been here awhile

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    Noticed this morning after a ride to work my coolant reservoir is empty,:eek1 About 2 months or so ago I had the hose recall done and all coolant was replaced with fresh. I cant recall if i really looked at the reservoir level at that time or if i have developed a leak of some sort. I haven't noticed anything leaking. Can I just top off the reservoir with Honda brand coolant since the nearest BMW dealer is over 200 miles away? I reckon i need to check my oil dipstick and make sure it aint a milky white!! :(:
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  2. raider

    raider Big red dog

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    If your reservoir is completely empty, once you've ruled out any leaks, it might pay to top the radiator up the old-fashioned way, through the pressure cap. I don't know if the radiator can draw water from the overflow reservoir if there is an air lock in the pipe between there and the radiator. After a complete radiator drain, it's quite possible the shop filled the reservoir, and then thermostats have opened and water jacket voids filled and so on and dropped the level considerably. I wouldn't worry unless it does it again.

    You can pour plain water into your radiator and it will work fine so long as you don't freeze it, albeit with a much reduced service life due to corroding fittings and mineral deposits gunking up the radiator core. The rest of the crap in coolant is anti-freeze, anti-coagulant, marker dye, algicide and corrosion inhibiter.

    There is no need to buy brand-name coolant - just check the package and see what the active anti-freeze ingredient is - usually ethylene glycol - and for pre-mixed packs, what its concentration is. Cross-check that against your owner's manual. If it's only a small top-up, the concentration doesn't have to be spot-on.
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  3. The Griz

    The Griz Long timer

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    Good advice!

    I'll add one thing. You can top of the coolant via the reservoir. Fill it up to the FULL line, then turn on the bike and run it for a bit. If the system needs more coolant, it will suck it in and use it. If it does this, then top it off up to the FULL line again and again until it holds at FULL.

    Use Prestone 50/50 premix in the yellow bottle.:thumb
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  4. BMWHillbilly

    BMWHillbilly Been here awhile

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    Thanks guys for your help. I do have one question. If i top it off at the reservoir ( fill to full line) do I need to run the bike with the reservoir cap on or off?
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  5. JoelWisman

    JoelWisman Long timer

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    Factory BMW coolant is ethelen glycol with long life additives. It is silicate free for alu service.

    It is the same thing as dex-cool which is commonly available only dexcool uses orange dye while BMW picked blue. The two together make brown but are compatible.

    Regular green etheline glycol won't hurt anything in small quantities, but the additive package is not as good or long lived.

    The concentration ratio is 50/50 unless you are somewhere that gets WAY below zero F, then it is 70% coolant, 30% water.

    In a perfect world you will use distiled water to mix with the anti freeze or buy premix.

    Do not use propelyn glycol, It is not comparable.

    I have no idea how to spell the fancy words above :)
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  6. The Griz

    The Griz Long timer

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    On
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  7. JoelWisman

    JoelWisman Long timer

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    the cap is just a dust cover, makes no difference if it is on or off other then your coolant will get dirty.

    When you run the bike, heat causes the coolant in the engine and radiotor to expand. This will force some coolant or air into the reservoir. You can run it all year and it will never drink anything from the reservoir.

    After running for a while, when you turn the bike off and the engine cools, the coolant in the system shrinks and coolant will be drawn from the reservoir.

    Think of this like blowing air into a soda through a straw. You cal blow all day and bubbles wil rise to the top but as soon as you suck, soda comes up the straw.

    Each time the engine gets hot, it blows some, as it cools it sucks some.

    If there is a BIG air void in your cooling system, this will not work as the coolant doesent expand enough to overcome cap pressure with a big air cushion. The F800GS is actually a bitch to purge the air from.

    But since you are not overheating, I'm betting there's not much air in there and remaining will be purged if you just top off the reservoir.
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  8. BMWHillbilly

    BMWHillbilly Been here awhile

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    thanks Joel. I will go by the Honda shop on the way home and get their premix coolant. I'm just baffled on why i have no coolant in the reservoir. Seems to me the shop should have checked that when they refilled with fresh coolant. On the other hand I dont recall looking at it myself as i should normally do after a service and that is my fault.:D
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  9. JoelWisman

    JoelWisman Long timer

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    yes, they should have, but it may have been full then.

    This bike really is a bitch to purge of all air out of.

    I've taken to warning people the level may drop some after a cooling service, and giving them some coolant if it's not easy to come back by.
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  10. BMWHillbilly

    BMWHillbilly Been here awhile

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    So your saying the coolant level will drop from the reservoir after a cooling service? How does that happen without a leak? Air gets purged at some point from the reservoir im guessing. Sorry for all the questions. I'm just a lil ol' southern girl learning the beemer ways. :D
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  11. Animo

    Animo Been n00b awhile

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    Right on that! I filled mine right up to the full line when the engine was cold..... and until I drained some of the coolant I had coolant all over the friggin' place as soon as the engine was hot. I scaled back on speed and the coolant shot out live a volcano, I was green stained! When cold fill it between the cold and hot lines max, or you will be green like me!<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" /><o:p></o:p>
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  12. JoelWisman

    JoelWisman Long timer

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    any time any job is done, such as removing a radiator hose, coolant is drained and air replaces it.

    When a tech is done, he will refill the radiator but there will still be air trapped in high points all over the cooling circuit in the engine.

    BMW had a procedure to bleed this air out of the cooling system but it doesent work.

    A few months back, BMW revised the procedure for purging the air from the cooling system, it's a better procedure but it still does not get all the air out.

    I personally use bmw's latest method and then run the engine at 5000 rpm while me and another guy tip the bike from side to side as far as we can.

    After that I test ride the bike initiating rapid starts and stops (wheelies and stoppies) and this usually gets almost all the air out but sometimes there's still a little inside.

    Any air left in the pressurized part of the cooling system will eventually make it to the radiator where it will get burped into the reservoir. After burping the engine will suck coolant from the reservoir to replace the area that the air took up in the cooling system.

    If a lot of air was left in the cooling system then it will drink all the coolant in the reservoir over time, even though there is no leak.

    Does that make sense?

    In any case, fill that reservoir back to the max line, and if it drops again, take it to a dealer to find out if it's leaking somewhere.

    Good luck, hope that answers your question.
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  13. BMWHillbilly

    BMWHillbilly Been here awhile

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    thanks Joel. you rock! :clap
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  14. ride2little

    ride2little Riding Like the Wind

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    Pop the rad cap, fill it, cap it back up. Run the bike squeeze the hoses like you're milking a cow (or at least how you would envision it). and repeat if necessary. this will purge your system of air bubbles.
    And yes. The blue Honda pre-mix is your best choice.
    Not a big deal really. Just don't procrastinate and do it as soon as you can.
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  15. BMWHillbilly

    BMWHillbilly Been here awhile

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    ok. Topped off the reservoir to the second line from the botton. I realize that is the "hot" level for full but im going by what yall said. :1drink Topped of the radiator to the bottom of the fill neck. it was a bit low. Ran the bike for about 10 minutes or so. Fan never did kick on. Anyhoo, I did not notice an overflow on the reservoir and if it is too much coolant where does the overflow go? i dont want to blow a hose and scald myself. :D
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  16. markymcd

    markymcd Been here awhile

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    One other thing you might want to check for leaks with your coolant system is your oil cooler next to your oil filter up front. there is an in and out hose that comes from your coolant hose. I had an issue with one of the hoses and o ring seals.

    better safe than sorry. I got one of the first '08s (650 twin) and i seem to get lots of the problems before they show up as a notice or a recall.

    cheers,
    Mark
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  17. BMWHillbilly

    BMWHillbilly Been here awhile

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    no leaks. oh wait.....i do have a leak but its the valve cover :D . thats another thread...lol.

    Anyone know if the reservoir has an overflow or does it just shot out the pinhole of the reservoir cap? :huh
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  18. raider

    raider Big red dog

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    I don't know where the overflow is, but there will be one. Worst case, the reservoir cap will pop off, but the water in the reservoir shouldn't be that hot and the reservoir cap is a dust seal, nothing more.
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  19. BMWHillbilly

    BMWHillbilly Been here awhile

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    ok. went for a spirited ride this morning. all seemed ok til i pulled in the carport. coolant leaking from an oil cooling line below the water pump. Looks like the hose has pulled away a fair bit enough to leak all over the carport. :cry This hose was not this way last night when i topped off and checked all hoses. could the system have too much pressure now to push off the hose clamp like that? All i did was to top off the radiator and fill the reservoir to the max line. what next to do? help!! Closest dealer is 200 miles away!!!!
    #19
  20. JoelWisman

    JoelWisman Long timer

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    No, the radiator should be full to the very top. Something is up. Can you post a picture of which hose or line?
    #20