ST1300 coolant leak

[ST1]

I have a ST 1300 A6 i noticed some coolant staining on the right hand side engine block.
i have removed the side cover to inspect.

I am starting the bike and getting it up to operating temperature to try and see where the leak is.

 

[GhenghisKen]

What about that crack in photo number#2 just to the left of that bolt?

 

[ST1]

I ran the bike for 15 minutes the fans came on as normal and stayed at three bars on the temperature gauge.
The round hole above the square one was a bit wet, i place a cotton bud inside and there are green marks.

The big bolt is a mount for the radiator.

 

[gordow88]

What about that crack in photo number#2 just to the left of that bolt?

good eye.

 

[SupraSabre]

This is what a water pump leak looks like:



And from the Square hole, coolant leaking from the valley or thermostat cover.

 

[SMSW]

What about that crack in photo number#2 just to the left of that bolt?

Looks to me like a casting flaw, not necessarily a crack.

 

[vstrom.zrxdude]

Water pump cover o ring groove corodes, cleaned,resealed my cover only with old o ring silicone sealer ,holds coolant good now,184500 mi on mine now never replaced wp mechanical seal

 

[dduelin]

Every ST1300 on the planet weep, seeps, or leaks coolant from umpteen hose connections, most of which are concealed under the rubber heat mat in the vee of the cylinder banks and/or behind the radiator. Once seen in the light of day it is a simple job to stop or reduce the leaks by slightly snugging up the OEM hose clamps or replacing them. The O-ring that seals the thermostat housing is also probably leaking. It’s not difficult to set things to right. I’m out riding today but when I get home, I will attach a PDF file with a tutorial on how to remove the radiator and access the thermostat housing if you haven’t already done that.

 

[eyrepb]

Looks to me like a casting flaw, not necessarily a crack.

I will guess a shadow of the rough edge from the light angle