Rode in to London today, traffic very very heavy (tube strike), engine hot, fan on and off but didn't go anywhere near the red zone. Parked up and noticed a few big drops of liquid under the bike but no dripping.

Dripping started when I started the engine. It's coolant, but it's cold? Even with the engine very hot?

I fitted a new thermostat recently but the leak is not from there.
I fitted a used water pump last year - perhaps that has gone again?

Haven't crawled underneath to have a look but suggestions will be welcome!

I intend to ride her home tonight - air-cooled - after the traffic has died down!

 

might just be from the overflow on the res bottle. has the level dropped in the radiator itself at all?
jeff

 

Jeff
Good idea, I'll check the rad and have a look behind the panels now that the engine is cool.
But would the res bottle leak only when the engine is running? It's coming out pretty fast, like 2 big drops a second.

 

had the same with my mark 1, turn it off and drips, is it comming out the overflow pipe, check where its routed, for some reason the pipe through the cap into the tank on mine went right to the bottom and when she warmed up the level was enough to push water out through the overflow, so i cut it off on the bottom level, and no more drips, have checked the tank a few times and the level is ok,

 

Unfortunately the coolant level has dropped in the filler neck and she's dripping when the engine is running.

Decided to get the RAC to take me home tonight, but might ask him if it's worth trying Rad-Weld or similar first (hopefully he'll have some with him).

 

If you fitted a new water pump, the O-ring where the chrome pipe fits to it may have been disturbed. Feel under the pump for fluid.

 

Tim, thanks for the info but the pump was fitted many months ago with new O-rings (the big one and the chrome pipe one), and it's been OK until today.

 

tighten the water pump hose , I find they always weep in colder weather

 

Thanks for the advice, folks, but the coolant is leaking out of the drain hole in the pump so I guess I need a new pump.

 

Sounds like the pump has gone for good this time.............

Bad luck hmmm
Still, could have been worse.
Not too difficult to change.