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F twins water pump issues

Texpaul

Lost again
I have a 2010 F650gs twin with 106K on the clock. It's going to be used by my son for a trip to Alaska this summer. I am curious if there is anyone out there with a high mileage F twin that can give me feedback on any waterpump issues they may have encountered. What was the issue, how did you find it/notice it, at what mileage?
Thanks in advance for sharing your knowledge.
 
It is not uncommon for the water pump to begin seeping either oil or coolant out of the weep hole under the water pump. There are o'rings that are supposed to contain both fluids and there is a small space between the o'rings where the weep hole located. This design is supposed to prevent coolant getting into the oil.

When this occurs you have some options. One is to ignore it. Annie's 650GS has been weeping a small amount of oil for 10,000 miles or more. It is a small dribble that is easily wiped away once a day or so. Option 2 is to replace the o'rings. I have some on hand and plan on doing so. I understand it can be difficult to get them seated correctly. I've read of a few failures. Option 3 is to replace the pump. The rub there is that a couple of years ago BMW switched the gear on the pump and drive gear on the cam to nylon gears. Your gears are steel and the cam gear must be changed to nylon, making the job more complex and expensive. I've read of this job going wrong as well after paying a dealer $600+. Option 4 is to find a workable older pump with steel gears. I have no idea how practical an idea that is
 
No weeping from the pump hole but I have noticed a lot clatter from the right, upper, portion of the motor (near area of the water pump). Power, fuel and oil consumption is unchanged and no overheating issues but I wonder if that noise might be water pump related, thus my question. Or is that just normal for a twin with lots of miles?
 
Cam chain rattle? Perhaps your tensioner is showing it's age. I've no experience working on a CCT on an 800 engine, but I imagine there will input from others that have.
 
Voni's F800S is in the 90K mile range now with now water pump issues. A little clatter at start up aggravates me.
 
Paul, I guess the question is, is the bike reliable enough for a long distance ride to AK?

I would say Voni's is. It has made the same noise since new. The tensioner is not difficult to replace. It screws into the back of the engine case. Some stuff in the way, of course.
 
As it turned out the issue was camchain rattle. MotoHank replaced the adjuster and the noise went away. Weird because the cam chain is on the left side of the motor but the noise seemed to be coming from the right side, which is why I suspected the water pump.
 
After over two years of having the water pump on Annie’s F650GS weep oil I finally got around to replacing the o’rings today. The job was not particularly difficult and the instructions in the service manual DVD were very helpful. I’ve had the replacement o’rings for nearly two years. If I remember correctly I paid less than $10 for four of them. I used STP to lube the o’rings so they would not bind and the pump went in quite easily. I brushed on a very thin film of Permatex Ultra Black gasket maker to seal the pump in the recess. A similar film that was applied during manufacture was present on the pump and took a bit of effort to remove. You will need a slide hammer to pull the pump and patience removing the clamps on the four coolant hoses attached to the pump housing. I let the bike idle until the fan came on and there was no sign of any coolant or oil weeping. Hope to get out for a ride in the next few days as the weather improves, but so far, so good.
 
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