Hi, I have a Sherco 2.9 - its around 2008.

Does anyone know the purpose of the small round hole (see picture) that is in the engine casing just below and in front of the water pump? mine starting leaking some 'foam' after I'd submerged the bike a bit, This was due to some water having mixed in with the gearbox oil.. That's all changed and bike running fine, luckily water was clean and I sorted it quickly.  Changed the oils, cleaned airbox and have flushed the rad as i suspected oil may some how of got in there (hence white foam).

Hole still weeps a couple of drips, clean water now, not foam - but only now and then.  I don't know what hole is designed to do - or if its on the water side (its close to pump, or oil side... 

Could easily just block the hole - but it must serve some designed purpose.

Thank you!  

I suspect that is for bleeding the cooling system. Remove the bolt clean around the area thoroughly and replace using a new copper washer

 

At a guess, it's a tell tale that you have a failing seal on your water pump.

Edited October 15, 20214 yr by b40rt

Water pump seal failing as b40 says.

I believe it is a designed "weep hole" to indicate failing water pump seal(s) as stated by b40rt and tshock250

If I remember correctly that is a 2 seal design, a seal for the coolant side and a seal for the oil side with a gap between.  The weep hole is situated in the gap between the seals.  

Benefit is you can tell which seal is bad by what is leaking out of the weep hole. but I would suggest changing both seals, because they have both been in there the same length of time with same use etc..

Thanks to all for the replies. I'll Google what's involved in changing the seals. 

This is for earlier Shercos but might still apply.

water_pump_seal_replacement.pdf

Thank you. Petfect

On 10/15/2021 at 11:55 PM, Somkid said:

Thank you. Petfect

Is yours actually leaking? Looks pretty dry in the pic.

It was, I fitted new water side seal, all good now thanks