Need confirmation on waterpump weep hole

[Rob F]

In my past inquiries on coolant leaks i have had quite a few members telling me that the waterpump weep hole normally has some leakage. That didn't seem right to me as i spent many years working on JD riding mowers and when they dripped fluid out of the weep hole there was definitely a problem.
This "don't worry about the weep hole leaking" scenario has been nagging at me so i started my detective work and i think that i found out something very interesting. I just need confirmation on this to finish off a theory.
So the question of the day is........... Do any of you riders that own a 2008 and up ST1300 have a fitting with a drain hose coming off the crankcase cover near the waterpump?
Where does that hose end up? Have you noticed coolant dripping out of the hose occasionally?
If i can confirm this, then my theory would go something like this:
From 2003 to 2007 there was no fitting and hose at the weep hole. There apparently were a lot of unnecessary waterpump replacements done under warranty because of customer complaints. When the weep hole leaks on a pre 2008 the coolant runs all over cover and along the oil pan and drips out of the plastics. Very messy and noticeable So to remedy ( or hide) this, Honda decided to install a drain hose( 2008 and up) and run it down somewhere so it would be less visible and messy.
My personal opinion is that there is a flaw in the waterpump design causing slight seepage past the seal. Perhaps sealing material, tolerances, soft impellershaft, ect. It was probably more cost efficient to just drill and tap the weep hole and ad a hose instead of redesigning the pump components.

 

[oude geit]

Mine is a 2007, so no weep hole tube. The amount of drainage is near nothing, just enough to make the case messy in a years time. It may drip from a hose since the engine heat is not burning off the water....jmo

 

[Andrew Shadow]

Correct you are, the design was changed as you described.
This discussion has been had here in the past and the result of these discussions agreed with what you have surmised, that the design was most likely for the reasons that you have listed.

How much of a leak is acceptable? I suspect that that varies based on everyone's comfort level most likely. If it is only a couple of drops from time to time, even if it is at every use but stops as soon as it warms up, I would adopt the wait and watch stance and wouldn't be going in there. When the drips become constant, regardless of the volume, that is when it is advising that it needs attention.

ST1300 - Water Pump Weep Holes

 

[jfheath]

I've seen that report too, and it seems very plausible.

This is 'Heath Logic', based on the assumption that if there is a weep hole, they expect the seal to weep a little bit. Being a small amount, it's not enough for me to worry about. 'Heath Logic' applies when I don't know enough about it, and when I really can't be bothered to tear everything apart on the offchance.

I belive that the weep hole is in a position such that any escaping fluid cannot then get into the seal between the shaft and the engine oil. It is just allowed to escape. I would imaging that the seal 'lips' are lubricated with fluid ?

While fluid is escaping in that way, providing it isn't excessive, then that seems to me to be a good thing. You'll see more when it is in the garage, because its temperature drops below 100C, and it will not evaporate as readily. I'd rather see that than not see any froma device that is expected to leak a little bit. If that was the case, where is it going ?

I will start to worry when either I see a large puddle of fluid on the floor of the garage; or my fluid reservoir level drops.

 

[Rob F]

Thanks for the advice and will take it into consideration. i will deal with the upper hose leaks and leave the pump for now but i have already ordered gaskets and parts for the job. They will be on standby . I may attempt to drill and tap a spigot hole into the crankcase cover. Depends on how brave i get.