water pump failure

[coconuttele]

Just wondering if my water pump is starting to go. I loose coolant in the overflow resivor after about 200 miles of rideing. It drops from the max to the min lines, but does not ever go below the min. Checked the raditor cap and all looks fine, cracked the bleeding cap on left side and coolant comes out. No visible leaks in the system and no puddles of coolant after sitting for the night. Just changed the oil today and no coolant in the sump or crank case. Any thoughts out there?

[MortimerSickle]

Try not filling higher than halfway between max and min when cold.

I keep mine just below half when cold, and it rises to just over max when hot.

When I tried filling to max when cold, it would overflow when hot.

[coconuttele]

not having a problem with it boiling over, it just disappears somewhere. checked all the overflow tubes and connections, just dont see a leak anywhere.

[Orangecicle]

Lean the bike over to the right (brake side) a little and pull out the oil filter. See if the veins in the oil filter are wavy. If so, it's probably a pump seal leak.

Lean the bike over on the left (clutch side) a little and pull off the clutch cover. Look inside the cover. If it look likes a latte in there, that's water mixed with oil. You have a pump leak.

Both checks take about 10 minutes total.

If you don't find anything, then the water may be leaving the system through another path. Head leaks generally pressurize the water system. I've not heard of a leak going out the tailpipe. Assuming that's not the case, then it could be that it's dripping out on the ground. If you think that's the case, duct tape something to catch overflow on the overflow pipe and see if it catches anything while riding. It could be that it's going out on the ground. In that case, you have one of two things. Either you have a radiator cap that's not sealing properly and pressurizing the system, or you have a leaking head gasket. Check your radiator cap to make sure that it is seating properly (i.e., clean on the rubber mating surface). I have a June 2004 build 950, and my radiator cap just started not sealing this past year, resulting in the bike puking fluid at various times. The solution was a new radiator cap.

Best of luck.

[MortimerSickle]

Mine doesn't boil either. It just expands enough to push the excess coolant out the expansion tank overflow hose.

If you are not loosing it there, I dunno.

You could have a bad head gasket, but I would think that would have other symptoms beyond loss of coolant, especially when the loss stops at the low mark.

I'm out of guesses, sorry.



Edit: 205ed by seconds.

[keener]

I have changed my radiator cap last year as precaution. What year is the bike?

from the HOW:

Radiator cap:

All years of 950 Adventures not very common but we've seen some 5-10 maybe... normal symptoms are of non-sealed system. ie: overheating, coolant not returning etc. Fix: new cap. (you will not find coolant in your oil due to this one!!!). May be related to casting sand in the system lodging itself in the seal and under the return valve. If your cap is doing this, chances are the sand is also eating up the waterpump shaft as well. Do a proper flush of the cooling system ASAP. It still may be too late for the waterpump seal. Watch your coolant level closely and be ready to replace the seal and shaft. Might not be a bad idea to do a preemptive overhaul of the waterpump anyway. It's generally easier in your's (or the dealer's) shop, than it is along the trail.

[keener]

you should see this thread is active now: http://advrider.com/forums/showthread.php?t=869805

[Zuber]

Very common for the radiator cap. Not the big seal, but the tiny little flapper in the center. It will get dirt/powder coating under it and not hold pressure. The fluid just disappears. I'm guessing it blows out as steam out the overflow bottle. Clean it out really good or replace.

I didn't see which bike you have, if it's newer than 07 it is probably not the water pump seal.

[coconuttele]

my bike is an 07 with 23,000 miles, i will try to clean the cap and see if that will help any.

[Guano11]

Originally Posted by MortimerSickle

Try not filling higher than halfway between max and min when cold.
I keep mine just below half when cold, and it rises to just over max when hot.
When I tried filling to max when cold, it would overflow when hot.

I've filled to the max line, thinking that if that's too much, the coolant will purge to reach its own "sweet spot" between the lines and stay there .
Is this not the case?

[MortimerSickle]

Originally Posted by Guano11

I've filled to the max line, thinking that if that's too much, the coolant will purge to reach its own "sweet spot" between the lines and stay there .
Is this not the case?

It's been a long time since I have filled beyond half, but I suppose that will work fine, as long as you don't keep refilling to max.