A friends sport 400 is getting water in the counter balancer oil. Before I take the motor apart I was wondering if anybody has encountered this problem before. The only water the bike has been in is the dew that falls at night. So I am thinking that it is coming from the water pump somehow. The coolant level does drop some. Just wondering if anybody has any ideas. Thanks.

 

It could be any of several problems. The most common is the head gasket is cracked or blown. Worse yet, it could be the head or cylinder. But I got my money on the head gasket.

 

425Xpedition,

There is another way water could be getting in. The venttube could be letting water in. It happened to me, until I routed the vent hoses through a hole in the frame. Problem solved. Just make sure your friend flushes the counter balancer oil several times until it comes out clear. I know it's a pain to change the oil, but it has to be done. If that isn't the case it's probably like Lurch said, a bad water pump seal.

 

Well the water is not coming in from the vent tube, the bike has only been ridden on asphalt. On the 400 water cannot get in from the head or base gasket. If the head or cylinder had a problem bike would not run right. It would fill up the crankcase with water. Guess I will just replace the water pump seals and see what happens.

 

It probably is the water pump seal. As long as it's not a whole lot getting in there, I would just keep the coolant topped off and change the counterbalance oil a couple times each year. It's a real headache to change the water pump seals on that bike. The engine has to be completely disassembled. If you're not real careful in doing it, you could accidentally damage something else and run into alot of extra costs. I would just wait until the engine needed a rebuild and change them out then. Antifreeze getting into the counterbalancer shouldn't corrode anything, so I'd just let it ride until it gets bad, if it ever does.

 

Walexa,

It is bad. The oil will turn to white pudding after one ride.