I am finally getting to pulling the water/oil pump for new seals.  I drained the oil.  How do I drain the coolant?  Is the bolt where the coolant temp sensor attaches also the point where the coolant drains?  

The coolant temp sensor is also your coolant drain plug.  Flows better if you loosen the rad cap first.

Do not over-torque the temp sensor when re-installing or it will tear apart. 9 Nm or 80 in-lbs

Thanks Duck.  I managed to extract the pump without any obvious damage to other parts of the engine. I plan to have the pump seals redone by someone who knows what they're doing.
To the untrained eye, the innards look pretty good. There was only very slight leaking of coolant, but I'd hate to have the riding season interrupted by an outright failure- especially on the road. I hope I can get it all back together without any unwelcome surprises. I did label the wires to the temp sensors, as they look identical.  I plan to use Permatex no-hardening gasket goop on the cover.  Anything to watch besides avoiding getting heavy-handed with the hex head screws when I button it all back up?

Though the seals wear out and can be replaced, the critical part is whether the metal shaft is worn/pitted.  If that's the case then new seals are not the solution.

Doing the seals isn't all that hard or complicated.  There's a few decent YouTubes about that cover it pretty well.

Take care when applying sealant to the surface between the sump and the pump,
so you don't block the oil return channel....or you very certainly would get a leak
in that area.

duck wrote:Though the seals wear out and can be replaced, the critical part is whether the metal shaft is worn/pitted.  If that's the case then new seals are not the solution.

Doing the seals isn't all that hard or complicated.  There's a few decent YouTubes about that cover it pretty well.

theres  more than couple of good posts in here about the oil/water seals
if you care to look

don't forget to lynish the shaft surfaces  where the seal fits up to the shaft
gives it new metal for the seal to reseal-mate onto, instead of pitted stuff
try this before committing to something really expensive


just a heads up

brickrider wrote:I am finally getting to pulling the water/oil pump for new seals.  I drained the oil.  How do I drain the coolant?  Is the bolt where the coolant temp sensor attaches also the point where the coolant drains?  

just undo the down hose on the outside of the crankcase to evacuate the most part ...where it meets up with the pump assembly ....

quick and easy ....big pan under to catch it all

Inge K. wrote:Take care when applying sealant to the surface between the sump and the pump,
so you don't block the oil return channel....or you very certainly would get a leak
in that area.

good reminder inge ......cheers !!!

charlie99 wrote:

brickrider wrote:I am finally getting to pulling the water/oil pump for new seals.  I drained the oil.  How do I drain the coolant?  Is the bolt where the coolant temp sensor attaches also the point where the coolant drains?  

just undo the down hose on the outside of the crankcase to evacuate the most part ...where it meets up with the pump assembly ....

quick and easy ....big pan under to catch it all

I did this once. On my 94 K1100RS. A couple of days later it left me having to do this fancy repair in a parking lot 700 miles from home. Of course it happened on a Monday when the BMW dealers are closed. 






Needless to say, I do not use that technique anymore. (And I always carry rescue tape now too.)