Water Pump leak, help?

[Hornet1998]

I recently replaced the radiator fan on my Hornet, did not touch the water pump at all but as soon as i turn it on, it leaks coolant from a small hole at the back of it.. Does anyone know why this has happened or how i can fix it?

[Pete.]

The pump seal bellows have split. The pumps are expensive little buggers. Usually you can only swap the pump but it is possible to swap out the seals if you're that way inclined.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[MCN]

As said by Pete, the pump seal is burst/broken.
They are two separate parts that rub together to form a seal.

https://en.m.wikipedia.org/wiki/End-face_mechanical_seal

The hole is there for two reasons, one to prevent water passing into the engine via the water pump drive shaft. And two, to let you see the seal is leaking.
It's called a Tell-Tale Hole.

Some pumps can be repaired by fitting a kit, some can be bridged and just the seal replaced and some cannot be opened to allow access. Factory sealed.
You may be lucky on eBay.

About £200 for a pump or £30 for a kit. (Guess)

I would do the kit if it were mine.

Or try this shit:

https://www.amazon.co.uk/KALIMEX-LTD-K-Seal-Coolant-Repair/dp/B001QT9KO6#immersive-view_1537812864858
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Disclaimer: The comments above may be predicted text and not necessarily the opinion of MCN.

[Hornet1998]

Thanks for the replies, where can I get these kits?
And so I understand better, would it be the gasket/water pump cover that's gone, no. 5 on this spares site?

https://www.bike-parts-honda.com/honda-motorcycle/600-MOTO/HORNET/1998/CB600FW/Engine/WATER-PUMP/13MBZW41/E__1000/1/1616

[rpsmith79]

Yep, same happened on my Hornet, according to the Haynes Manual, the hole is there as an indicator/bypass, so that when the seal fails, water drips from here rather than going into the engine itself and mixing with the oil

It is a non-servicable part, so replacement only

I got lucky and bought a 2nd hand one of eBay for about £30 and a new gasket for a a few quid, new they are over £150

In you link, it's the part with no number that has gone, the part with the shaft sticking out (all included in item 3)
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Current Bike: Honda CG125 ES4 // Honda CB600FS Hornet // Triumph Street Triple R

[MCN]